Editor-in-chief Subhash C. Dadeya, Editor-in-chief Neha Goel, Editor Volume 24 No. 6, May-June, 2019
Subhash C. Dadeya
Savleen Kaur Shibal Bhartiya
Patrons Executive Editor Executive Editor
A.K. Gupta G. Mukherjee
Gurbax Singh L.D. Sota AAnsisshisataSnetthEdGiutoprta MAsosnisictaanLtoEhdcihtoabr AsJsigisytaasnatSEadhiutor APasslliasvtai nDtoEkdaintoiar
Madan Mohan M.S. Boparai, P.K. Khosla
Editorial Photo Essay
Chief Advisory Board
Atul Kumar, Cyrus Shroff Harbansh Lal, Lalit Verma 5 Enigmas Behind the Lens 48 Focal Chorioretinal Atrophy in
Mahipal Sachdev Radhika Tandon
Rajendra Khanna, Rishi Mohan, Ritu Arora , Sympathetic Ophthalmia
R.V. Azad, S. Bharti, Sudarshan Khokhar,
Y.R. Sharma Featuring Sections 50 Coat’s-Type Retinitis Pigmentosa
52 Spectral Domain Optical
Editors
Neha Goel, Savleen Kaur Shibal Bhartiya Expert Corner Coherence Tomography in
8 Management of Post-operative Congenital Retinal Macrovessel
Assistant Editors
Anisha Seth Gupta Monica Lohchab Endophthalmitis Case Reports
Pallavi Dokania Jigyasa Sahu 55 Bilateral Optic Disc Edema
in Retinitis Pigmentosa with
International Advisory Board Review Articles Bardet-Biedl Syndrome
Arvind Chandna Derek Sprunger, Frank Martin 14 Diabetic Retinopathy 57 A Case of Identity – Tamoxifen
J. Panarelli, Larson Scott Saurabh Jain, Seyhan Obzkon 20 OCT Demystified
Sonal Ferzavandi Surabhi Shalini
Perspectives Toxicity
National Advisory Board
A.K. Khurana, B.N. Gupta B.S. Goel, Barun Nayak 28 Pearls in Recognizing Polypoidal News Watch
C haitra Jaidev, Chand Singh Dhull Deepak Mishra, D. Ramamurthy Choroidal Vasculopathy (PCV) 60 DOS Times Quiz
Dharmender Nath Gursatinder Singh 32 Vision Loss Following Pars Plana
Hemalini Samant, Jagat Ram Jai Kelkar, Kamaljeet Singh Vitrectomy 62 DOS Crossword
Krishna Prasad Kundlu Manisha Rathi, Mangat Dogra
R.K. Bansal, Ragini Parekh Rakesh Porwal Recent Trends and Advances Tear Sheet
S.P. Singh, Sandeep Saxena Sanjeev Nainiwal 36 OCT Angiography- Current 79 Retinal Vascular Occlusions
Sudesh Arya, Santhan Gopal Santosh Honavar Applications
Shreya Shah, Sudhir Kumar Swapan Samantha, T.S. Surendran 40 Multicolor Imaging in Retinal (RVO)
V. Saharanamam Vandana Jain, Vinita Singh and Choroidal Diseases
Virendra Agarwal Yogesh Shukla
Techniques
Delhi Advisory Board 44 Double Handshake Technique:
A.K. Grover, Abhinandan Jain Ajay Aurora, Ajay Sharma Modified Technique for Removal
Alkesh Chaudhary Amit Chopra, Amit Khosla of Retained Metallic Intraocular
Anju Rastogi Anuj Mehta, Anup Goswami
Arun Baweja, Arun Sangal Ashwini Ghai, Ashu Agarwal, Foreign Bodies
B.P. Guliani, Bhavna Chawla Dinesh Talwar
D.K. Mehta, G.K. Das H. Gandhi, H.S. Sethi, H.S. Trehan
J.K.S. Parihar, J.S. Titiyal Jatinder Bali, J.L. Goyal
J olly Rohatgi, Kamlesh, K.P.S. Malik K.R. Kuldeep, Kamal Kapoor
K irti Singh, Lopa Sarkar, M. Vanathi M.C. Agarwal, M.L. Bharti
Mahesh Chandra Manisha Agarwal
Meenakshi Thakkar Mohita Sharma
Mukesh Sharma N.Z. Farooqui, Nabin Pattnaik
Namrata Sharma, Neeraj Sanduja, Noshir Shroff
Om Prakash O.P. Anand
P.K. Pandey, P.K. Sahu, P.N. Seth Pawan Goyal, Piyush Kapur
Poonam Jain, Pradeep Sharma Praveen Malik, Punita K. Sodhi
Rajendra Prasad, Rajesh Sinha Rajiv Bajaj, Rajiv Garg,
Rajiv Mohan, Rajiv Sudan Rajpal, Rakesh Bhardwaj
R.B. Jain, Ramanjit Sihota Rakesh Mahajan, Rohit Saxena
Sagarika Patyal Sandhya Makhija
Sanjay Chaudhary Sangeeta Abrol, Sarita Beri
Sarika Jindal, Satish Mehta Shashi Vashisht
Sunil Chakravarty, S.N. Jha Suma Ganesh, S.M. Betharia
Sushil Kumar, Tanuj Dada Taru Dewan, Tushar Agarwal
Tinku Bali, Umang Mathur Usha K. Raina, V.K. Dada
V.P. Gupta, V. Rajsekhar V.S. Gupta, Vinay Garodia
Viney Gupta, Vipul Nayar Yogesh Gupta
Section Editors
Strabismus & Oculoplasty
Paediatric Hardeep Singh
Ophthalmology Mridula Mehta
Abhishek Sharma Rachna Meel
Annu Joon, Anirudh Singh Seema Das
Deepali Mathur Sumita Sethi
Geetha Srinivasan Neuro-ophthalmology
Rasheena Bansal Promita Dutta, Satya Karna
Renu Grover, Sumit Monga Swati Phuljhele, V. Krishna
Glaucoma Retina
Deven Tuli, J.S. Bhalla Bhumika Sharma
Mainak Bhattacharya Bhuvan Chanana
Manavdeep Singh Darius Shroff
Reena Chaudhary Deependra Vikram Singh
Cataract & Refractive Devesh Kumawat
Abhishek Dagar Koushik Tripathy
Charu Khurana Naginder Vashisht
Reena Sethi Raghav Ravani
Ritika Sachdev R.P. Singh, Ritesh Narula
Sanjiv Mohan Vinod Kumar Agarwal
DOS Correspondents Cornea & Oular Surface
Divya Kishore Manisha Acharya
Manisha Mishra Noopur Gupta
Mohit Chhabara Parul Jain, Pranita Sahay
Prateeksha Sharma Rajat Jain
Richa Agarwal, Shweta Dhiman Uma Sridhar
Sumit Grover, Yashpal Goel Vikas Veerwal
DOS TIMES
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DOS EXECUTIVE MEMBERS
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5 DOS Times - May-June 2019
Editorial
Enigmas Behind the Lens
Dear colleagues and friends!!
I am very pleased to write this editorial for yet another exciting issue of DOS
Times, which has a special focus this month on posterior segment disorders.
As we enter into this era of increased number of cataract surgeries,
my colleagues compile preferred practice patterns on postoperative
endophthalmitis. Dealing with Post-op endophthalmitis is a daunting task
not only for the surgeon but also for the patient as well. The numerous drugs
available as well as their relative advantages and disadvantages can make the
job more challenging.
As a resident, we expect all of you to be thorough with one topic that is diabetic
retinopathy. It is a growing epidemic which will be a very common disease
encountered by you all in your practice.
As more exciting technologies come in the market, OCT and OCT Angiography Dr. (Prof.) Subhash C. Dadeya
are the next big innovations in posterior segment diseases. This issue also
talks about multimodal imaging which is the most futuristic topic in retinal disorders.
We hope that the present assortment of beautiful cases and reviews appear as exciting to the residents as well as to
older colleagues. The surgical discussions may help you in your real life scenarios in daily surgeries.
I thank the editorial team, all our voracious readers and constant contributors to the DOS Times. We wish you all a
pleasant reading with this issue.
Before I conclude I wish to acknowledge every DOS member who entrusted me with this singular honour of holding the
reigns of DOS as your General Secretary and Editor DOS Times and sincerely hope that I made you all proud in all that I
did. I am at loss for words to express my gratitude to you all and will forever treasure this opportunity to serve you.
Thanks,
Dr. (Prof.) Subhash C. Dadeya
Secretary - Delhi Ophthalmological Society
Room No 114, 1st Floor, OPD Block,
Guru Nanak Eye Centre, Maharaja Ranjit Singh Marg,
New Delhi - 110002
Email: [email protected], [email protected]
Mobile: 9968604336, 9810575899
WhatsApp: 8448871622
www. dos-times.org 7
Reports
From the desk of President DOS (2018-2019)
This being the last issue of this newsletter, I would like to thank the entire team
working for the timely printing and release of DOS Times
DOS Times has become an integral part of ophthalmic community of Delhi and
NCR as it provides knowledge, information and updates on Ophthalmology. When
I visited different hospitals during the monthly meets around the Capital, I saw the
copies of DOS Times everywhere and was happy to see that many were using them as
reference text
The expert’s column in ophthalmology had views from seniors on how they tackle
problems using the experience they gathered while working on these situations. Prof. (Dr.) Sudarshan Kumar Khokhar
Prospective and Recent advances covered the recent the latest Global trends on
specific topics. Review articles were the most beneficial to the residents as it provided them with knowledge on the subject in
details covering all articles on the same. Photo essay and Case reports encouraged the residents to write their cases along with
faculty members, the quiz was a hit among residents as they learn the topic by solving these small puzzles.
Knowledge should reach every member of DOS and in doing so DOS Times plays a major role!!
With best regards.
Prof. (Dr.) Sudarshan Kumar Khokhar
President DOS (2018-19)
Professor of Ophthalmology,
Rajendra Prasad Centre Ophthalmic Sciences,
All India Institute of Medical Sciences,
New Delhi, India.
8 DOS Times - March-April 2019
Expert Corner
Management of Post-operative
Endophthalmitis
Dr. Dinesh Talwar Dr. Alkesh Chaudhary Dr. Padmamalini
Mahendradas
Endophthalmitis remains an uncommon but serious cause of visual loss. Over time, there have been changes in terms of predominant
causes, infecting organisms, and antibiotic susceptibilities. There is controversy regarding the use of intracameral prophylactic
antimicrobials during cataract surgery. Also, there is increasing evidence against routine use of topical antibiotics for intravitreal
injections. There are also increasing reports of multidrug-resistant organisms causing endophthalmitis, but the combination of
vancomycin and ceftazidime appears effective for the vast majority of cases. Future trends may involve increasing utilization of
polymerase chain reaction for diagnosis, and a lower threshold for pars plana vitrectomy for treatment of endophthalmitis.
We therefore asked a panel of renowned vitreoretinal specialists from all over the country to discuss their views on the various
aspects of management in these cases and to shine light on certain grey areas in these cases. The questions have been prepared by
Dr. Neha Goel (NG) Vitreoretina and Uvea Consultant, ICARE Eye Hospital and postgraduate institute, NOIDA, U.P., India.
(DT): Dr. Dinesh Talwar, Sr. Consultant Ophthalmologist and Vitreo Retina Specialist, Centre for Sight, & Indraprastha Apollo
Hospital, New Delhi, India.
(AC): Dr. Alkesh Chaudhary, Director & Consultant Vitreo Retinal, M.D. Eye Care and Laser Centre, Greater Kailash Part-II, New
Delhi, India.
(PM): Dr. Padmamalini Mahendradas, Head, Uveitis and Ocular Immunology, Narayana Nethralaya Eye Institute,, Rajajinagar,
Bangalore, India.
10 DOS Times - March-April 2019
NG: With regards to acute post-operative Expert Corner
endophthalmitis (following cataract surgery),
what are the commonest causative organisms hours, the drugs of choice are vancomycin and
in your practice, along with their relative ceftazidime. For acute endophthalmitis within
frequencies? the first 24-72 hours, the drugs of choice are
vancomycin and amikacin. But in cases which occur
DT: The frequency of gram negative organisms has within 24 hours either meropenum or tazobactam-
increased in past decade accounting for possibly piperacillin would be the drug of choice.
over half the culture positive cases. AC: Vancomycin (1mg) and Ceftazidime (2.25mg) in
0.1ml.
AC: Acute endophthalmitis typically is defined as PM: Vancomycin + Ceftazidime
occurring within 6weeks of surgery. Commonest
organisms are Staphylococcus species esp. NG: 3: Do you routinely administer intravitreal
S.epidermidis. Gram-negative like Pseudomonas dexamethasone in the first instance?
and anaerobes are much less frequent. Fungi are
usually Candida and Aspergillus. DT: No.
AC: Avoid administering intravitreal dexamethasone
PM: We commonly see gram positive organisms such as
staphylococcus aureus and streptococcus viridans. unless proven non-infective.
Rarely, fungal and gram-negative bacilli. Since PM: No, only after establishing the etiology and/or
ours is a tertiary referral center, post-operative
endophthalmitis cases are frequently referred from under antimicrobial cover do we prefer to give
other centers. We do see few sporadic cases in our intravitreal dexamethasone
center, but no cluster infections so far.
NG: 4: Which systemic antibiotic(s) do you
NG: What is the immediate management protocol recommend, if at all?
of a patient clinically diagnosed as acute post-
operative endophthalmitis? DT: Oral ciprofloxacin 750 mg twice a day along
with Amikacin 500 mg IV 12 hourly and Gudcef
1: Do you prefer an AC tap or a vitreous tap or (Cefpodoxime) 200 mg twice a day.
vitreous biopsy?
AC: Oral Cefpodoxime 200mg +Clavulanate 125mg and
DT: Along with the intravitreal antibiotics, we carry intravenous Cefazidime 2gm (8hrly), Amikacin
out an ac tap. We avoid a vitreous tap and do 7.5mg/kg stat and then 6mg/kg (12hrly). Besides
AC: vitreous biopsy only if patient is being taken up for fortified topical antibiotic eye drops.
PM: vitrectomy as the management.
Dry vitreous aspiration with 23G cutter is always PM: Oral ciprofloxacin is our preferred drug.
my preferred option.
We prefer to plan our management depending on NG: What are the indications of pars plana
the clinical presentation. AC tap is done if the patient vitrectomy in acute post-operative
has predominantly anterior segment involvement. endophthalmitis following cataract surgery
If there is posterior segment involvement, a that you follow? Would you recommend sticking
vitreous biopsy is taken at the time of vitrectomy in by Endophthalmitis Vitrectomy Study / EVS
a majority of cases. guidelines (1995) or switching to “complete and
early vitrectomy” in the current era?
NG: 2: What are the intravitreal antibiotics
administered empirically? DT: Any patient with a visual acuity of < cf close to face
or with vitreous exudates obscuring the view of the
retina would be considered for vitrectomy. So too
would any endophthalmitis presenting within 48 hr
of surgery.
DT: For an acute endophthalmitis occurring after 72
Figure 1(a): Acute post operative endophthalmitis following cataract surgery. BCVA was PL + PR accurate. Ultrasound B scan showed vitreous cavity
full of exudates with inferior retinal detachment. (b) Clinical photograph following immediate pars plana vitrectomy with IOL explant with intravitreal
antibiotics and silicon oil in situ. Vitreous biopsy revealed coagulate negative Staphylococcus. BCVA was 6/24. (c) Silicon oil removal with secondary
(scleral fixated) IOL was performed 3 months later. Final BCVA was 6/18 N 18.
www. dos-times.org 11
Expert Corner f. Start vitrectomy from the mid periphery, create a
hole in the posterior vitreous surface and extend
In case the patient is found during vitrectomy to the hole keeping the retina under visualization.
have a total or partial PVD with easy clearance
of the vitreous and exudates from the retinal g. After completing the vitrectomy at the centre, do
surface without any retinal breaks, conventional peripheral vitrectomy using indentation to keep the
vitrectomy is often adequate. In case there is severe underlying retina under visualization.
endophthalmitis with vitreous exudates upto the
retinal surface and especially if PVD had to be h. Use of the wide field systems improves visualization
induced during vitrectomy, a complete vitrectomy in hazy media.
with silicon oil endotamponade is preferred. So
there is a role for conventional vitrectomy in the Corneal epithelial debridement can make
milder cases of endophthalmitis and complete visualization significantly better.
vitrectomy with silicone oil tamponade in the
severe cases. AC: 1 into 10 dilution betadine drops and peri-
ocular betadine coat to be done 10-15 minutes
AC: Early vitrectomy is always a key to success if no preoperatively.
response within 24 hr. of injecting intravitreal
antibiotics with the advent of current safe and • 25G/23G vitrectomy with 5000 to 7000 cutting rate
better vitrectomy techniques. is a preferable mode.
PM: If the patient is not responding to intravitreal • Debulking of exudative material as much as possible
antibiotics and the endophthalmitis is worsening, from anterior and posterior chamber both.
in severe cases and in gram negative infections we
prefer to do a complete or early vitrectomy. Reinjecting intravitreal antibiotics per-operative at
closing.
NG: Please elaborate practical tips during pars
plana vitrectomy in acute post-operative PM: 1. If the view is hazy, an AC wash after taking an AC
endophthalmitis for enhancing safety and tap helps
outcomes?
2. An undiluted vitreous sample collection, if possible
DT: for a microbiological evaluation, helps in better
a. Check tip of infusion before starting the infusion response to treatment
fluid. A 6 mm cannula or a cannula without the 3. A core vitrectomy or complete vitrectomy without
trocar if required can help in case the cannula tip is any retinal breaks whenever possible. Complete
not visible on depression using the endoilluminator vitrectomy may not always be possible due to poor
for visualization from the corneal surface. visibility.
b. Do not use an old cutter.
c. For taking vitreous biopsy sample, ensure there is 4. Intravitreal antimicrobial agents in the appropriate
no adrenaline or antibiotic in the infusion. dosage at the end of surgery
d. Often there is a thick fibrin membrane occluding the
pupil and the iris surface. It is possible to remove this 5. Silicone oil injected if the eye has hypotony or
from the pars plana ports by making a Peripheral associated with intraoperative retinal breaks or if
iridectomy in the upper temporal quadrant with the there is retinal necrosis/thinning or if follow-up is
vitreous cutter and then dislodging the membrane unpredictable
by sweeping a MVR blade across the iris surface.
The dislodged membrane can be removed by the 6. Lensectomy or cataract extraction for better view
cutter. and outcomes.
e. Use the highest cut rate with low suction to prevent
traction on the retina. NG: What peri-operative measures are adopted
during cataract surgery to minimize the
incidence of endophthalmitis? What is your
opinion on routine use of intracameral
antibiotics?
DT: Use of preoperative povidone iodine with a total
contact time of 3 min (one drop before entering
the OT, one drop when put on the OT table and 5-6
Figure 2(a): Endophthalmitis diagnosed a month after uneventful cataract surgery. Note the exudates present over the iris surface inferiorly. BCVA was
hand motions. (b) Clinical picture following immediate pars plana vitrectomy with intravitreal antibiotics. BCVA was 6/18. Vitreous biopsy showed
Candida sp. (c) Fundus photograph showing resolving retinal haemorrhages over the posterior pole.
12 DOS Times - March-April 2019
drops to completely cover the conjunctival sac after Expert Corner
putting the speculum which is washed off after
45 second of contact time is probably the most NG: What clinical features and investigations
important factor in preventing endophthalmitis. 3 can differentiate infective from “sterile
minute contact time of povidone iodine on the lids endophthalmits” or exaggerated post-operative
and adjacent face are also important. inflammation / TASS syndrome?
Intracameral Moxifloxacin is probably the best
option for prophylaxis at the end of surgery and is DT: Predominantly corneal edema more in central
safer than cefuroxime. region, lack of pain, higher IOP would all go in
AC: Pre-operative broad-spectrum antibiotic drops like favour of TASS.
moxifloxacin/Gatfloxacin 3 times a day X 3 days.
• At the day of surgery re-examine the eyes for any AC: Rapid onset within 12 to 24 hrs.
redness, discharge and lid hygiene. • SLE shows increased cells and with associated
• Rule out any systemic infection.
• Blood sugar level less than 200 in case of Diabetics. fibrin and possible hypopyon.
• Peri-ocular Betadine paint and 1in 10 dilution • Diffuse corneal edema, iris atrophy, raised IOP.
betadine drops 10-15 minutes before surgery. • Respond rapidly to treatment with topical
• For patient fresh cap and OT dress.
• At OT table flushing of conjunctival sac twice with corticosteroids.
betadine solution and cleaning the lid margins with Regular assessment for control of IOP and
a bud soaked in betadine solution.
• Water proof sterile draping with drainage pouch. inflammation.
We don’t advocate intracameral antibiotics. PM: TASS usually occurs in the immediate postoperative
PM: 1. Peri operative topical betadine use with adequate
contact time period or within 24 hours, conjunctival congestion
2. Minimize operative time with less handling of tissue is less, corneal involvement will be limbus to limbus
3. Avoid posterior capsule rent with no posterior segment involvement and they do
Yes, we recommend the use of intracameral well with intense topical steroid therapy.
moxifloxacin. Endophthalmitis causes sudden decrease in vision,
pain and redness in the eye, significant posterior
NG: How does your management protocol segment involvement and there is worsening with
differ in cases with chronic post-operative intense topical steroid therapy.
endophthalmitis following cataract surgery?
NG: With increasing number of intravitreal
DT: Would consider complete vitrectomy with injections, the incidence of endophthalmitis
vitreous biopsy sample for culture and PCR and following them is also on the rise. How does
cytopathology. the microbiological profile differ in your
experience?
AC: Usually manifests several weeks or months after
surgery, less common and less virulent bacteria and DT: Have been fortunate not to have had
fungi as compare to acute variety. endophthalmitis following intravitreal anti VEGF
agents. The only endophthalmitis I have had was
• Obtain AC and vitreous samples. following Ozurdex and was Pseudomonas in which
• Identification of organisms is key to success. despite all intervention finally the vision was lost.
• Intravit Vancomycin / Cefadizime.
Often need PPV with removal of IOL with capsule. AC: Streptococcus species has been reported more
PM: Depending on the causative organism the common in endopthalmitis occurring post injection
as compare to post surgical being the stahylococus.
management differs. If it is a low-grade bacterial
infection, we treat the patient with topical, PM: Low virulent gram-positive organisms or culture
intraocular and systemic antibiotics with or without negative bacterial infections are most commonly
intravitreal dexamethasone with or without pars seen in post injection endophthalmitis in our
plana vitrectomy. In patients with P Acne infection, practice.
we inject the intracameral vancomycin in the bag,
if the infection is not abating prior to surgical NG: What should be the immediate management
intervention. In case of fungal endophthalmitis, of a patient clinically diagnosed as acute
we treat our cases with intravitreal voriconazole endophthalmitis following an intravitreal
or amphotericin B along with systemic antifungal injection?
agents. If anterior segment involvement is
significant, we add topical antifungal agents. DT: Intensive topical antibiotics (my preference:
Intravitreal dexamethasone is given under the cover Vigamox 1 hourly, concentrated tobramycin eye
of antifungal agents to control the inflammation. drops 1 hourly and if available concentrated
cefazolin eye drops 1 hourly with Atropine eye
drops 4 times a day, prednisolone eye drops 4 times
a day provided there is no corneal infiltration and
lubricant eye drops. Along with these, systemic
antibiotics are also started. Follow up is done daily.
AC: Immediate intravitreal vanco+cefatizime injection
followed by early vitrectomy.
PM: Anterior chamber tap followed by intravitreal
www. dos-times.org 13
Expert Corner
antibiotic injection along with topical and systemic theater the procedure should be performed.
antibiotic therapy. • Always use the fresh vial for the injection.
• Cap and mask and sterile gloves to be used.
NG: What are the crucial measures that can • Injection in both eyes simultaneously should be
be adopted to decrease the incidence of
endophthalmitis following intravitreal avoided.
injections? • All precautions to be taken like normal operative
DT: Use of preoperative povidone iodine with a total Procedure.
contact time of 3 min (one drop before entering • I always use a disposable kit for every eye containing,
the OT, one drop when put on the OT table and 5-6
drops to completely cover the conjunctival sac after speculum + fixed caliper+ 4buds+waterproof drape
AC: putting the speculum which is washed off after +sponges and gauge pieces. Fresh disposable
• 45 second of contact time is probably the most syringe and 30G needle.
• important factor in preventing endophthalmitis. 3 • Following all these measures, I didn’t even a single
• minute contact time of povidone iodine on the lids case of post-injection enophthalmitis in my OT.
and adjacent face are also essential. PM: a. Meticulous lid margin and ocular surface
Giving injections in the OT in a sterile environment, examination before injection
cleaning the rubber stopper on the vial with b. Betadine ocular surface cleaning
alcohol, ensuring that all OT staff entering OT where c. Topical betadine application with good contact time
injections are being given have covered their nose d. Sterile technique of injection in a dedicated
properly with the masks, minimum movement in injection room/operation theatre
the OT are all important to decrease the incidence e. Post injection topical betadine application
of endophthalmitis.
Sterilization of ocular surface is of paramount Compiled by:
importance. Dr. Neha Goel
Pre-procedural, topical broad-spectrum antibiotic ICARE Eye Hospital and Postgraduate
drops for 3-4 days. Institute, NOIDA, India
Per-operative – periocular betadine coating and
providine (1 in 10 dilution) drops 5-10 minutes
before injecting and betadine (half strength) ocular
wash on the table.
Under total aseptic conditions in sterile operation
14 DOS Times - March-April 2019
Review Article
Diabetic Retinopathy
Dr. Sonalee Mittal MS, Dr. Dinesh Mittal MD
Drishti The Vision Eye Hospital, Indore, India.
Diabetic Retinopathy remains the leading cause Figure 2: Hard exudates.
of blindness among 25 and 75 years of age.
Diabetic Macular Odema is the leading cause
of decrease in vision in Diabetic Retinopathy.
Other causes of decrease in vision in diabetic
retinopathy is macular ischaemia, retinal and
viterous haemorrhages and tarctional retinal detachment. For
last three decades various studies has been done which added
in our understanding and treatment of diabetic retinopathy.
Recently with the advent of anti VEGF therapy a milestone has
been achieved and has ushered in a new era . This review article
reviews the management of diabetic retinopathy keeping in
view the findings of latest studies.
Diabetic retinopathy (DR) is the leading cause of blindness
among 25 and 75 years of age. DR affects 75% of patients
after 15 years of disease duration .The rate of progression to
proliferative diabetic retinopathy (PDR) is highest among the
type 1 diabetic patients. In type 1 diabetes, 25% after 15 years
and 42% after 25 years develop PDR. In type 2 diabetes, 16%
will progress to PDR after 15 years.
Clinical Picture Diabetic Retinopathy
DR is a microangiopathy of retinal vasculature. Earliest
change is thickening of basement membrane and loss of
pericyte.
Micoaneurysms
Micoaneurysms are hypercellular saccular outpoucings of
capillary wall and appear visibly as deep red dots . They are the
first visible clinical sign of DR.
Figure 1: Micoaneurysms. Figure 3: Intra retinal haemorrhages.
16 DOS Times - May-June 2019
Hard exudates
Hard exudates are sharply demarcated yellowish white
deposits in the retina. They are extravascular deposits of
lipid rich material that result from spillage and incomplete
resorption of lipoproteins. They often present at the border
between edematous and non edematous retina. They may exist
as circinate ring pattern around the vessels with increased
permeability or microaneurysms.
Intra retinal haemorrhages
Progressive capillary closure and resulting retinal
Mittal S. et al. Diabetic Retinopathy
Review Article
Figure 4: Cotton wool spot. Figure 5: Over the past 30 years, macular edema Figure 6: thickening of retina at or within
has been classified according to two Definitions. 500 µm of center of macula.
Figure 7: hard exudates at or within 500 µm of Figure 8: zone of retinal thickening one Figure 9: Proliferative diabetic retinopathy.
center of macula associated with thickening of disc area or larger any part of which is
adjacent retina. within one disc diameter of center of
macula.
ischaemia leads to intraretinal blood-retinal barrier in the retinal Evaluation
microvascular abnormalities (IRMA), capillaries and/or RPE.
intraretinal haemorrhages and venous Previous history of diagnosis
abnormalities (eg venous beading). Intra Diabetic macular odema (DME) or treatment if any should be taken
retinal haemorrhages may appear as dot is defined as retinal thickening of the thoroughly.
blot or flame haemorrhages. Dot Blot posterior pole and detected by slit lamp
haemorrhage are typically small and biomicroscopy or optical coherence Comprehensive eye examination
with sharp demarcated border. Flame tomography (OCT). including visual acuity, intraocular
Haemorrhages are located in nerve fiber 1. ETDRS (early treatment diabetic pressure measurement, slit lamp
layer. They are larger and have wispy examination of anterior segment and
margins. retinopathy study) defines Clinical dilated funduscopic examination should
Significant Macular Odema (CSME) be done. Ophthalmoscopy in a dilated
Cotton wool spot on biomicroscopy as. pupil remains the standard for clinical
2. DIABETIC MACULAR EDEMA (DME). diagnosis and further classification.
Cotton wool spot are small white This definition, rather than CSME, is Posterior pole examination is best done
patches with wispy border. They are used in the era of optical coherence with slit lamp biomicroscopy with
ischaemic area affecting nerve fiber layer. tomography (OCT) and retinal accessory lenses. Imaging modalities
pharmacotherapy. This is defined as commonly used in the management
Diabetic macular odema a 2 DD area of macular thickening, are fundus photography, flourescein
any part of which is within 1 DD of angiography (FA) and optical coherence
Retinal nutrition is supplied by two the fovea. Thickening is determined tomography (OCT).
distinct circulations: the choriocapillaris by OCT scanning.
nourishes the outer third of the retina Fundus photography is used in
and the two vascular layers (superficial Proliferative diabetic clinical practice to document the status of
plexus in the axon and ganglion cell layers, retinopathy retinopathy and evaluate the progression
deep plexus in the inner nuclear layer) of retinopathy. It helps in record keeping
of the retinal circulation nourish the Proliferative diabetic retinopathy , information sharing and images can be
inner retina. Two distinct, though often (PDR) is characterised by formation used as teaching tool.
coexisting, types of diabetic maculopathy of new vessels and fibrotic tissue on
are seen: ischemic maculopathy results retina and optic disc. Contraction of OCT and FA
from capillary dropout, and macular fibrous tissue lead to tractional retinal
edema results from breakdown of the detachment and viterous haemorrhage. OCT and FA are the most useful
investigations in DME.
Mittal S. et al. Diabetic Retinopathy www. dosonline.org 17
Review Article
Figure 10: OCT macular odema Figure 11: diabetic macular odema OCT. Figure 12: diffuse leak on fa and
types. cystic macular odema on oct.
Figure 13: Mild NPDR. Figure 14: Moderate NPDR.
Figure 15: Moderate NPDR FA. Figure 16: Severe NPDR.
OCT role in DME Rule out macular ischaemia Classification
• Confirm presence of macular edema Color Fundus Photography is more
• Know type of macular edema sensitive than OCT in identifing the Mild non proliferative diabetic
• Assess macular thickness location and severity of hard exudates, retinopathy (NPDR)
• Know response to IV retinal haemorrhages, microaneurysms
and vascular abnormalities. Color fundus Few microaneurysms or
pharmacotherapy photography is the investigation of choice haemorrhages may be present.
• For follow up and documentation to classify the diabetic retinopathy.
Slit lamp biomicroscopy, color fundus Moderate NPDR
Increasingly OCT is being used for photography or ophthalmoscopy may not
evaluation of macular edema. Spectral be able to detect mild macular edema. Haemorrhages, microaneurysms,
domain (SD OCT) has replaced time Here OCT is very helpful in measuring cotton wool spots, venous beading or
domain OCT (TD OCT) central foveal thikness. OCT has become IRMA may be present.
the gold standard in monitoring the
OCT ANGIOGRAPHY progression and treatment response Severe NPDR
in DME patients. It give micrometer
OCT angiography is being sensitive measurements in central retinal 4-2-1 rule
increasingly used to find vasculature thickness. Any one of following three features
status. is considered diagnostic of severe NPDR
1. all 4 quadrants contain severe
FA role intra retinal haemorrhages or
microaneurysms
Type of leak focal or diffuse 2. venous beading in 2 or more
18 DOS Times - May-June 2019 Mittal S. et al. Diabetic Retinopathy
Review Article
Figure 17: NVD. Figure 18: NVD FA. Figure 19: NVD with haemorrhage.
for high risk PDR
PDR with HRCs
1 NVD equal to or greater than ¼ to
1/3 disc area.
2 NVD any amount with vitreous or
pre retinal haemorrhage.
3 NVE equal to or greater than ½ disc
area with fresh vitreous or pre retinal
haemorrhage.
Management
Modification of systemic risk factors
• Control of blood sugar
• Control of blood pressure
• Lowering of lipid levels
• Exercise and food habbits
Figure 20: NVE. Prevention of
Table 1: Management of DR Primary prevention of diabetes
o Daily exercises
TYPE OF DR MANAGEMENT o Reduce weight
o Healthy eating habbits
PDR with HRCs do PRP (Pan Retinal Photocoagulation o Regular blood sugar checkup
DRS study)
Secondary prevention
To prevent development
complications of diabetes
o Intensive control of blood sugar
o Control of blood pressure
o Decrease of blood lipids
Severe NPDR and early PDR consider for PRP (ETDRS STUDY) Tertiary prevention
Early and mod NPDR no PRP, regular follow up Prevention of visual loss
o Screening through a dilated pupil by
Size of burn Table 2: PRP protocol
Time 500 µm skilled eye care provider for early
Intensity argon laser burn .1 second detection and treatment of diabetic
Distance between spots of moderate intensity retinopathy .
Sittings placed one half to one burn apart ETDRS (early treatment diabetic
divided between 2 or more sittings. retinopathy study) protocol for full
scatter laser provides useful guidelines
quadrants. very severe NPDR. Management of macular
3. IRMA in at least 1 quadrant. odema
Early PDR
If any two of above three features are New vessels and criterion not met If thickening involves centre of fovea
present, retinopathy is considered to be then treat otherwise wait.
ETDRS recommends treatment if
CSME is there.
Mittal S. et al. Diabetic Retinopathy www. dosonline.org 19
Review Article
Figure 21: These should be atleast two Figure 22: PRP. Figure 23: Intravitreal injection
weeks apart if two sittings and at least 4
days apart if three or more sittings.
Figure 24: Invitreal injection technique. Figure 25: AVASTIN vial. Figure 26: Triamcinolone vial.
Table 3: Modified-ETDRS Focal/Grid Laser Photocoagulation Technique Used and Afiberplast are practically equally
by the DRCR.net effective in management of DME.
Bevacimizumab is more commonly used
Grid treatment 500–3000 μm superiorly, nasally, and inferiorly from center because it is more economical.
of macula;500–3500 μm temporally from macular center; no
burns placed within 500 μm of disc Role of steroids in DME
Burn size 50 μm
Retisert, illuven (flucinolone
Burn duration 0.05–0.1 seconds
acetonide), ozurdex (dexamethasone
Burn separation Two visible burn widths apart
implant) and triamcinolone (1mg and 4
Direct treatment Directly treat all leaking microaneurysms in areas of retinal
thickening between 500 and 3000 μm from the center of the mg) has been tried.
macula DRCR.net shows Intravitreal steroids
Spot size 50 μm
alone are inferior to laser or Intravitreal
Burn duration 0.05–0.1 seconds
anti VEGF agents . It has been further
shown that Intravitreal anti VEGF agents
with or without laser are superior to
intravitreal steroids combined with laser.
TreatmentofchoiceisINTRAVITREAL three Intravitreal anti vegf injections are IV steroids has main complication of
ANTI VEGF RANIBIZUMAB (LUCENTIS given and then switched to as required
, ACCENTRIX , RAZUMAB) .3 mg in .03 PRN dosing .One can add IV injection of cataract and glaucoma.
ml or IV BEVACIMIZUMAB (AVASTIN, steroid triamcinolone 2mg / .05 ml in
MVASI) 1.25mg in .05 ml. or aflibercept patients who are not responding to anti In pseudophakic patients Intravitreal
(eylea) 2mg in .05 ml. vegf agents. Triamcinolone plus laser benefit is
DRCR.net protocol I recommends Protocol I DRCR.net conclusively comparable to Intravitreal anti VEGF
treating centre involving DME with 4 proves the superiority of Intravitreal anti
to 6 Intravitreal injections of anti VEGF VEGF agents with early or deferred laser agents and superior to that seen in laser
agents till the macula is relatively dry over laser alone or laser with Intravitreal
followed by focal laser .In cases of non steroids or Intravitreal steroids alone. group. Aflibercept,
centre involving DME, focal or macular Ranibizumab,
grid is recommended. To reduce the Protocol T DRCR.net conclusively
burden and cost of injections usually proves that all the three anti VEGF Dexamethasone ozudrex implant and
agents Ranibizumab, Bevacimizumab flucinolone implant use in DME are
approved by FDA. Bevacimizumab
(Avastin) and Triamcinolone are used off
label.
20 DOS Times - May-June 2019 Mittal S. et al. Diabetic Retinopathy
Review Article
Figure 27: Burn parameter two visible Figure 28: In nutshell Some clinical presentations 1 Figure 29: 2 Severe NPDR with centre involving
burns width apart Grid Laser. Moderate NPDR Vision 6/6 both eyes. Do observation Macular Odema
& No treatment.
Figure 30,31: PDR with no macular odema. Do PRP Figure 32: 4 Pt. of PDR with DME involving
centre or having CSME
Table 4: So final recommendations
6. Early Treatment Diabetic Retinopathy
Disease Study treatment Study Research Group. Treatment
techniques and clinical guidelines for
PDR + HRC DRS PRP photocoagulation of diabetic macular
edema: Early Treatment Diabetic
Severe NPDR ETDRS Consider PRP Retinopathy Study Report Number 2.
PDR Without HRC Ophthalmology. 1987;94:761-774.
MILD & Moderate NPDR ETDRS NO PRP 7. Diabetic Retinopathy Clinical Research
Network. Randomized trial evaluating
Centre Involving Macular DRCR.net Protocol I Intravitreal Anti VEGF ranibizumab plus prompt or deferred
Odema laser or triamcinolone plus prompt
laser for diabetic macular edema.
Centre Sparing ME ETDRS Focal Or Grid Laser Ophthalmology 2010;117:1064–77.
Modified ETDRS focal / grid laser report from the Diabetic Retinopathy 8. Gross JG, Glassman AR, Jampol LM, et
protocol as used by DRCR .net Study. The Diabetic Retinopathy Study al. (DRCR.net Protocol S). Panretinal
Research Group. Arch Ophthalmol photocoagulation.
Vision 6 /18 in involved eye 1979;97:654–5.
3. Editorial: The Diabetic Retinopathy Correspondence to:
Do FA, OCT Study. Arch Ophthalmol 1973;90:347– Dr. Sonalee Mittal
FA shows focal leak OCT shows 8. Drishti The Vision Eye Hospital
macular odema. 4. Photocoagulation treatment of Vijaynagar, Indore, Madhya Pradesh, India
Intravitreal Avastin injections two proliferative diabetic retinopathy.
or three depending upon response Clinical application of Diabetic
supplemented by focal green laser. Retinopathy Study (DRS) findings,
DRS report number 8. The Diabetic
REFRENCES Retinopathy Study Research Group.
Ophthalmology 1981;88:583–600.
1. Preliminary report on effects of 5 Early Treatment Diabetic Retinopathy
photocoagulation therapy. The Diabetic Study Research Group. Techniques
Retinopathy Study Research Group. Am for scatter and local photocoagulation
J Ophthalmol 1976;81:383–96. treatment of diabetic retinopathy:
Early Treatment Diabetic Retinopathy
2. Four risk factors for severe visual Study Report no. 3. Int Ophthalmol Clin.
loss in diabetic retinopathy. The third 1987;27:254-264.
Mittal S. et al. Diabetic Retinopathy www. dosonline.org 21
Review Article
OCT Demystified
Dr. Sonalee Mittal MS, Dr. Dinesh Mittal MD
Drishti The Vision Eye Hospital, Indore, India.
Optical coherence tomography is easy to use, Figure 1: OCT Principle.
noninvasive, reproducible, safe. It is obtainable
through most media opacities, including vitreous Figure 2: Time Domain OCT working.
hemorrhage, cataract. Recent advances allow for interference.
a dramatic improvement in the cross-sectional
image resolution with improved acquisition It uses infrared light from a super‑luminescent diode
speed. OCT is helpful in the interpretation of pathologies in that is divided into two parts: one of which is reflected from a
all layers of the retina as well as the vitreous–retinal interface. reference mirror and the other is scattered from the biological
OCT is also used for the detection and monitoring of optic tissue. The two reflected beams of light are made to produce
nerve, glaucoma and anterior chamber pathology. Its helps in interference patterns that makes up an A‑Scan. A‑Scans that
high-resolution evaluation of tissue pathology at cellular level,
achieving axial resolution of up to 2–3 μm in tissue. There is Mittal S. et al. OCT Demystified
direct correspondence to the histological appearance of the
retina, cornea, and optic nerve in health and disease. OCT is a
critical tool in the diagnosis and monitoring of ocular disease
involving the retina, choroid, optic nerve, and anterior segment.
Optical Coherence Tomography
Optical coherence tomography (OCT) is a quick, non contact,
non invasive and reproducible imaging modality that generates
micrometer resolution cross sectional images of ocular tissue
for macular lesions and has become an essential part of retina
practice. During the past two and a half decades, OCT has evolved
to become an essential tool in ophthalmology. OCT is analogus
to Ultrasonic B Scan and radar imaging and produces a two
dimensional image of backscattered light from different layers
of retina. OCT is an optical analog of ultrasound imaging that
uses low coherence interferometry to produce cross‑sectional
images of the retina. Its ability to noninvasively image detailed
ocular structures and associated microvasculature in vivo with
high resolution has revolutionized patient care.
Optical coherence tomography (OCT), first described by
Huang et al. in 1991, allows high-resolution cross sectional
(tomographic) images of the neurosensory retina in a
noninvasive manner. Commercially available OCT systems are
now capable of obtaining retinal images with an axial resolution
of approximately 2 to 3 μm, and a transverse resolution of
approximately 15 to 20 μm. The lateral resolution is limited by
the diffraction caused by the pupil and it is normally about 20
μm. As a result, OCT has been characterized as in vivo “clinical
biopsy” and has transformed the diagnosis and management of
vitreoretinal disorders.
BASIC PRINCIPLES
OCT works by measuring the properties of light waves
reflected from, and scattered by, tissue. The use of light waves
in OCT results in images with much greater resolution than
ultrasonography as the wavelength of light is many times less
than that of sound. OCT instruments employ the principle of
22 DOS Times - May-June 2019
Review Article
Figure 3: Spectral Domain OCT working. Figure 4: OCT resolution.
Development of OCT are captured at adjacent retinal locations
by transverse scanning mechanism are
1971 CONCEPT OF 1996 IST COMMERCIAL combined to produce two-dimensional
SEEING INSIDE TISSUE OCT MACHINE cross-sectional image of the target tissue
known as a B-scan. If these B-scans are
1991 IST OCT IMAGE OF repeated at multiple adjacent positions
RETINA using a raster scan pattern, then a three-
dimensional volume of structural and
2000 SECOND 2006 COMMERCIAL flow information can be compiled.
GENERATION OCT SPECTRAL DOMAIN
TIME DOMAIN OCT
OCT
In the earliest OCT systems, these
2002 THIRD interference patterns were assessed as a
GENERATION STRATUS function of time - “TIME DOMAIN” OCT. In
1993, the first Time Domain OCT device
TIME DOMAIN OCT capable of in vivo use in humans was
developed termed Stratus OCT (ZEISS).
2012 SWEPT Adaptive Optics Although Time Domain OCT systems are
SOURCE OCT OCT capable of generating high resolution
images (8-10 μm for Stratus OCT), they
2014 OCT require the use of a mobile reference
ANGIOGRAPHY mirror for the assessment of interference
patterns - a requirement that limits their
image acquisition speed (400 A-scans per
second for Stratus OCT). This is a major
restriction for clinical practice as only
sparse coverage of the macular area was
possible when acquiring any given image
set.
SPECTRAL DOMAIN OCT
Fortunately, this technological
LAYERS OF RETINA HISTOLOGY AND OCT hurdle has been overcome in recent
Histologically, the retina consists of ten layers, four of them are cellular and two are neuroyenaarlsjuwncitthionths.e introduction of Spectral
Most layers can be identified with SD-OCT. The layers of the retina as seen on histologic sDeocmtioanin, iOnCT - a technology that removes
the requirement for a mobile reference
order from the inner to outer retina, are listed here.
Retinal Layers mirror by the assessment of interference
1 internal limiting membrane (ILM) patterns as a function of frequency rather
2 nerve fiber layer (NFL; axons of the ganglion cell layer) than of time.
3 ganglion cell layer (GCL) Spectral domain OCT systems
4 inner plexiform layer (IPL) use spectral interferometry and
5 inner nuclear layer (INL) a mathematical function (Fourier
6 outer plexiform layer (OPL) transformation) to assess interference
F87igeouxurettee5rr:nDnauilfcfleilmereaintrtinllaagyymeerrse(moOfNbrerLta;inntahe.e(EnLuMcl)ei of photoreceptors) patterns as a function of frequency. Thus,
light scattered from different depths
9 rod and cone inner segments (IS)
M9itrtoaldSa. netdacl.oOneCTouDteemryssetigfimede nts (OS) www. dosonline.org 23
Mittal sonalee et al
Review Article
Figure 6: Different layers of retina on OCT. Figure 7: SD OCT image of a normal individual INTERNATIONAL
CONSENSUS.
within the tissue can be measured 8 external limiting membrane (ELM) outer nuclear layers are hyporeflective.
simultaneously, and images can be 9 rod and cone inner segments (IS) Correlation of OCT images with the
acquired 50 to 100 times more quickly 9 rod and cone outer segments (OS)
than in time domain systems (typically 10 retinal pigment epithelial cells (RPE) microstructure of the outer retina is less
over 50,000 A-scans per second). well defined.
The first in vivo imaging of the OCT showing different retinal Four bands in the outer retina
human retina using spectral domain layers
OCT was reported in 2002. Each of The innermost band has been
the recently introduced commercial The high axial resolution offered attributed to the external limiting
Spectral Domain OCT systems is capable membrane (ELM). This band is typically
of acquiring sizable image sets over by OCT is particularly well suited to thinner and fainter than the others.
short time periods. As a result, new
methods of utilizing these image sets assessment of the multilayered retinal The second of the four bands has
have evolved, significantly enhancing been commonly ascribed to the boundary
the evaluation of vitreoretinal disorders. structure. On OCT false-color B-scans, between the IS/OS photoreceptors, but a
Fundus photography and fluorescein highly reflective tissue is reddish-white in recent consensus that this band correlates
angiography yield diagnostic information color, while hyporeflective tissue is blue- with inner segment ellipsoid zone (EZ).
about retinal topography. OCT provides black in color.
information that is like cross sectional The third band is referred to as
biopsy and complimentary to topography. In most scans, the first hyperreflective either OS tips or as Verhoeff membrane.
OCT resolution is very high as compared layer detected is the internal limiting This third band correspond to the contact
to resolution of Ultrasound, CT scan, MRI cylinder between the RPE apical process
images. membrane (ILM) at the vitreoretinal and the external portion of the cone
outer segment, and has been called the
LAYERS OF RETINA HISTOLOGY interface. In a subset of the population, interdigitation zone.
AND OCT
the posterior hyaloid may be seen as The fourth hyperreflective outer
Histologically, the retina consists of a thin hyperreflective layer above the retinal band is attributed to the RPE,
ten layers, four of them are cellular and ILM. Next to ILM is hyperreflective NFL. with potential contribution from Bruch’s
two are neuronal junctions. Outer to NFL is hyporeflective ganglion membrane and choriocapillaris.
cell layer. Outer to ganglion cell layer is
Most layers can be identified with hyper reflective inner plexiform layer. Retinal Thickness
SD-OCT. The layers of the retina as seen Next is hyporeflective inner nuclear layer
on histologic section, in order from the of bipolar cells. Next is hyper reflective Different segmentation algorithms
inner to outer retina, are listed here. outer plexiform layer. Next is hyper from different instruments tend to follow
reflective External Limiting Membrane. different borders and therefore result
Retinal Layers Within the retina, the ILM, RNFL and both in different measurements. The OCT
1 internal limiting membrane (ILM)
2 nerve fiber layer (NFL; axons of the the inner and outer plexiform layers and
ELM are seen as hyperreflective layers
ganglion cell layer) while the ganglion cell layer, inner and
3 ganglion cell layer (GCL)
4 inner plexiform layer (IPL) Table 1: Different types of diabetic macular odema
5 inner nuclear layer (INL)
6 outer plexiform layer (OPL) 1 Diffuse retinal thickness Sponge like generalized mild hypo reflective swelling
7 outer nuclear layer (ONL; the nuclei of retina
of photoreceptors) 2 Cystoid macular odema presence of intra retinal cystoid areas of low
reflectivity & separated by higher reflectivity septa
3 Serous retinal detachment focal elevation of neurosensory retina overlying a
hyporeflective dome shaped space .
4,5 Viteromacular interface may involve epiretinal membrane or vitreo macular
abnormalilities traction or both
24 DOS Times - May-June 2019 Mittal S. et al. OCT Demystified
Review Article
Figure 8: Dffuse retinal thickening. Figure 9: Cystoid macular odema.
Figure 10: Serous retinal detachment. Figure 11: Posterior Hyaloid traction.
Figure 12: Posterior hyaloid traction with tractional retinal Figure 13: CSR.
detachment.
software automatically de¬termines the uses variation (or decorrelation) in the diabetic retinopathy.
inner and outer retinal boundaries. Inner OCT signal to detect motion in biological
boundary is ILM and outer boundary tissues. OCTA can noninvasively detect the Steps toward interpretation
varies in different OCT models. movement of red blood cells at capillary- of an OCT image
level resolution. OCTA is particularly
Spectralis SD-OCT instrument useful for detecting regions of impaired 1. Determine the indication for the OCT
follows the posterior surface of the RPE perfusion and neovascularization. OCTA from the patient’s record, fundus
complex, the Stratus TD-OCT instrument has been used to evaluate many of pictures, angiograms, etc., Does the
follows Band #2 (ellipsoid zone or pathological macular changes in retinal OCT image show the area of interest?
inner segment–outer segment (IS/ vascular diseases, including diabetic
OS) junction), and the Cirrus SD-OCT retinopathy, retinal vein occlusion, 2. Is the scan protocol used appropriate
instrument follows the anterior edge of macular telangiectasia, and neovascular for the information required?
the RPE layer. Normal subjects central ARMD.
retinal thickness is 265 µm with CIRRHUS 3. Is the scan quality good enough for
OCT. OCTAADVantage&DISADVantage analysis? Identify artifacts, other
findings that could affect image
OCTA OCTA is at least as good as dye studies quality
for assessing macular complications
OCT is a noninvasive imaging method of retinal diseases, such as diabetic 4. Use the Macular cube, 3D, or volume
that has been used extensively in the field retinopathy, retinal venous occlusion. scans for evaluation of the pathology
of ophthalmology since 2002. OCTA is a The main limitation of OCTA is the field in to, including the segment maps.
functional extension of OCT and is being of view, but this is rapidly improving. Color or grayscale images are both
used increasingly to detect microvascular Neovascularisation is detected best by FA. adequate
changes in many retinal diseases since
approval by US FDA in 2016. Fundus colour photograph is still 5. Evaluate each layer from
the gold standard to grade the severity of the posterior vitreous to the
OCTA is an imaging modality that choroidoscleral junction if visible,
for deviation from the normal.
6. Classify the abnormality into one
Mittal S. et al. OCT Demystified www. dosonline.org 25
Review Article
epithelium and neurosensory retina
Posterior hyaloidal traction
SD-OCT showing attached posterior
hyaloid inducing some tractional effect
possibly exacerbating the underlying
edema. The hyper reflective foci with
posterior shadowing represent small
exudates
Figure 14: VMT. patterns of DME: with Posterior hyaloidal traction (more
1. Diffuse retinal thickening severe form) with tractional retinal
Figure 15: Stage 1 macular hole. 2. Cystoid macular edema detachment.
3. Serous retinal detachment
Figure 16: Full thickness macular hole. 4. Posterior hyaloidal traction Of these, the most common pattern
or more of the following: change in 5. Posterior hyaloidal traction is diffuse retinal thickening (39.5%), and
contour, change in thickness, change the least common are posterior hyaloidal
in reflectivity, loss of tissue, presence tractional retinal detachment traction (12.7%) and tractional retinal
of abnormal tissue. Look for the detachment (2.9%).
location of the abnormality, layers Diffuse retinal thickening
involved either primarily or as part Serous retinal detachment is more
of secondary effects. SD-OCT showing sponge-like common in males and patients with a
swelling, low reflective, expanded and high serum triglyceride.
7. Look for the presence of known irregular areas of the retina, and small
biomarkers before making the final amount of sub foveal fluid . Patterns that are significantly
diagnosis. associated with a decrease in visual
Cystoid macular edema acuity are diffuse retinal thickening, CME,
OCT IN DIFFERENT RETINAL and posterior hyaloidal traction.
DISEASES SD-OCT showing hypo-reflective
fluid-filled cystic cavities within outer OCT measurements are more
OCT Differentiate various retinal layers, separated by hyper sensitive and reproducible indicator of
presentations of diabetic macular edema, reflective septae of neuroretinal tissue. change in retinal thickness than color
monitor the course of CSR, fundus imaging, supporting the use of OCT
Serous retinal detachment as the principal method for documenting
differentiate lamellar / pseudo / full- retinal thickness.
thickness macular holes, detect macular SD-OCT showing fluid accumulation
odema in vascular occlusions and helps between the detached retinal pigment However, OCT is less suitable
on making treatment decisions in ARMD. than fundus imaging for documenting
Diabetic Macular Edema the location and severity of other
morphologic features of diabetic
Kim proposed a classification of five retinopathy, such as hard exudates,
retinal hemorrhages, microaneurysms,
26 DOS Times - May-June 2019 and vascular abnormalities.
Central Serous Chorioretinopathy
CSR
CSR is an idiopathic syndrome that
typically affects young to middle-aged
males and is characterized by serous
detachment of the neurosensory retina.
Focal and multifocal areas of leakage
secondary to increased permeability of
the choroidal vessels and a barrier defect
at the level of the RPE have been described
in the pathogenesis of this disorder.
OCT shows serous detachment of the
neurosensory retina above an optically
clear, fluid-filled cavity, associated with a
pigment epithelial detachment.
Note thickened choroid, pigment
epithelial detachments & significant
subretinal fluid.
OCT is also used to quantify and
monitor amount and extent of subretinal
fluid, thickening of neurosensory retina
and diminution of choroidal thickening
after treatment.
Mittal S. et al. OCT Demystified
Review Article
Full-thickness macular holes can
be either primary (if caused by VMT) or
secondary (if caused by other conditions
unrelated to abnormal vitreoretinal
traction), and can be further subclassified
by the size of the hole measured on SD-
OCT.
Based on macular hole width,
macular holes are divided as follows:
Small holes measure 250 μm or less,
medium size holes are between 250 μm
and 400 μm, and large holes are larger
than 400 μm.
Figure 17: Central retinal vein occlusion MACULAR ODEMA. CRVO Central Retinal Vein
Occlusion
In NON ISCHAEMIC CRVO there is no
significant macular edema . In ischaemic
CRVO there is significant cystoid macular
edema with subretinal fluid.
Figure 18: Dry ARMD changes in both eyes. life with a 2:1 female preponderance. Age-Related Macular Degeneration
Symptoms include decreased visual
PVD vs VMA vs VMT acuity, metamorphopsia, and central AMD is a common cause of
scotoma. A full-thickness defect in the irreversible vision loss among the elderly
In normal eyes, as the vitreous neural retina as seen with OCT can worldwide. AMD can be classified in
liquefies due to age, it detaches from the differentiate a true macular hole from a two forms: non neovascular (dry) and
macula. In some people, an unusually pseudo hole seen clinically. Pseudo holes neovascular (wet or exudative). The non-
strong adhesion is present between the are seen in the presence of a dense sheet of neovascular form accounts for 80–90%
vitreous and macula, and as the vitreous ERM with a central defect that overlies the of cases while the neovascular form
detaches peripherally, it continues to pull foveal center, giving the ophthalmoscopic accounts for 10–20% of cases, but was
on areas of the macula. appearance of a macular hole. responsible for majority of severe vision
loss (80–90%) prior to widespread use of
The vitreoretinal adhesions transmit GASS Macular Hole STAGES VEGF inhibitors.
tractional forces to the retina from the
vitreous body, having the potential Gass stage 1 impending hole is OCT may be a useful ancillary test
to cause tensile deformation, foveal characterized by a foveal detachment in any stage of AMD. In patients with
cavitations, cystoid macular edema seen as a yellow spot (1A) or ring (1B) dry AMD, the high-definition averaged
(CME), limited macular detachment, or a in the fovea. Spontaneous resolution will B-scans are useful to assess the ultra-
macular hole. Patients can present with occur in approximately 50% of these structure of drusen and to examine
visual loss and metamorphopsia. cases. adjacent retinal layers that can be
compromised by the disease process.
VMA and VMT In stages 2-4, there is a full-thickness
VMA is defined on OCT as retinal defect, with a complete absence of The progression of early AMD
neural retinal tissue overlying the foveal to severe forms, such as GA, can be
“perifoveal vitreous separation with center. What differentiates these stages monitored by using OCT.
remaining vitreomacular attachment is the Size of the retinal defect (<400 μm
and unperturbed foveal morphologic in stage 2 and >400 μm in stage 3) or the The loss of RPE and photoreceptors
features.” presence of a complete posterior vitreous are easily observed in the OCT B-scans.
detachment regardless of hole size (stage
Vitreomacular traction VMT, on the 4). OCT identifies GA as a bright area
other hand, is defined by “anomalous resulting from the increased penetration
posterior vitreous detachment OCT MACULAR HOLE STAGES of light into the choroid where atrophy
accompanied by anatomic distortion of This classification divides macular has occurred in the macula.
the fovea.” Pseudocysts, cystoid macular
edema and subretinal fluid are typical holes based on the cause, size of hole, and Drusen appear clinically as focal
findings of VMT. the presence or absence of vitreomacular white–yellow excrescences deep to the
adhesion. retina. They vary in number, size shape,
Macular Hole and distribution and are seen as discrete
areas of RPE elevation with variable
Idiopathic macular holes typically reflectivity.
occur in the sixth to seventh decade of
OCT can be used to identify some
of the wet AMD features, such as the
presence of intraretinal or subretinal
fluid, presence of retinal PEDs, which can
be classified in serous, fibrovascular, and
hemorrhagic PEDs.
Mittal S. et al. OCT Demystified www. dosonline.org 27
Review Article
CONCLUSION During past two and a half decades, Correspondence to:
OCT has evolved to become an essential Dr. Sonalee Mittal
Undoubtedly, for many tool in ophthalmology. Its ability to Drishti The Vision Eye Hospital
ophthalmologists, not only for retinal noninvasively image detailed ocular Vijaynagar, Indore, Madhya Pradesh, India
specialists, OCT is the leading tool for structures and microvasculature in vivo
their practice. The number of fluorescein with high resolution has revolutionized
angiography examinations has been patient care. OCT has changed the
reduced in the last 10 years with an approach of ophthalmologists in their
important increase of OCT procedures. daily practice.
The future will be more interesting with
the full introduction of OCT angiography,
wide-field OCT, and adaptive OCT.
28 DOS Times - May-June 2019 Mittal S. et al. OCT Demystified
Perspective
Pearls in Recognizing Polypoidal Choroidal
Vasculopathy (PCV)
Dr. Prashant Jain
Consultant Vitreo retina and Uvea, ICARE Eye Hospital and Post Graduate Institute, Noida, India
Polypoidal choroidal vasculopathy (PCV) was Figure 1: Color fundus photo showing PCV types (a) Exudative; (b)
first described by Yannuzzi et al. in 1990 as Hemorrhagic; (c) Mixed; (d) Peripheral PCV.
having two distinct components of branching
vascular network (BVN) and terminal aneurysmal choroidal vasculature. It has been considered to be a variant
dilatations or polyps associated with or without of neovascular age-related macular degeneration (AMD). The
serous/hemorrhagic detachment of retinal aneurysmal dilatations, also known as polyps, may be found
pigment epithelium (RPE)1. at subfoveal, juxtafoveal, extrafoveal, peripapillary or even
The prevalence of PCV varies among different ethnic groups peripheral regions. These polypoidal dilatations may be visible
and has a higher prevalence in Asians and blacks compared as reddish-orange subretinal nodules during ophthalmoscopic
to Caucasians2. PCV accounts for 25%–50% of Asian patients examination. The clinical classification of PCV is as follows
presenting with presumed neovascular AMD3–6 whereas (Figure 1):
it is observed in only 5%–10% of Caucasian patients with a) Exudative: Presence of lipid exudation with either serous
neovascular AMD7–9. There is a marked male preponderance of
63%–78.5% and only 5.9%–24.1% have bilateral disease10–12. macular detachment / intra-retinal fluid or serous PED
The Beijing Eye Study 2011, a population-based study in b) Hemorrhagic: Sub-retinal or Sub-RPE hemorrhage /
Northern China, attempted to estimate the prevalence of PCV
using a combined clinical and optical coherence tomography Hemorrhagic PED
(OCT) criteria to define the presence of PCV. In this study, c) Mixed: Presence of features of both exudative and
PCV was defined as an elevated orange-red lesion on fundus
photographs, characterized by a double-layer sign (DLS) and hemorrhagic variety
high dome-shaped pigment epithelial detachment (PED) on
the OCT images. With this definition, the authors found a PCV Imaging in PCV
prevalence of 0.3±0.1%11.
The gold standard for diagnosing PCV is by indocyanine ICGA is considered to be the current gold standard for
green angiography (ICGA), which shows the presence of a detection and evaluation of PCV.
branching choroidal vascular network and/or clusters of
dilated polypoidal lesions13,14. The polypoidal lesions are best detected on indocyanine
The treatment options for PCV include anti-VEGF and green angiography (ICGA) and might be associated with a
verteporfin PDT. Anti-VEGF agents improve visual function by branching vascular network (BVN) of neovascularization
restoring normal retinal thickness, reducing the serous macular (Figure 2). Since fluorescein angiography (FA) findings of PCV
detachment (SMD), taking care of BVN, and reducing reuptake can mimic those of occult choroidal neovascularization (CNV)
of VEGF after PDT while PDT facilitates polyp regression. in neovascular AMD, visualization of the abnormal polypoidal
The efficacy of these treatments as monotherapy versus lesions with ICGA is required to differentiate PCV from CNV
combination therapy was previously evaluated in a randomized in neovascular AMD. ICGA can demonstrate single or multiple
controlled trial (EVEREST). The results showed that PDT, used polyps as vascular aneurysmal dilatations arising from inner
in combination with ranibizumab or used alone, is superior to choroidal vessels in the early phase as hyperfluorescent spots
ranibizumab monotherapy in achieving polyp regression.
Through this article we will discuss few pearls in Jain P. Pearls in Recognizing Polypoidal Choroidal Vasculopathy (PCV)
recognizing PCV. It is a question that has been controversial
in ophthalmology over many years: Is PCV a subtype of
neovascular age-related macular degeneration (AMD) or
a separate clinical entity? Even more important, does this
distinction affect treatment and outcomes?
Clinical Classification
Polypoidal choroidal vasculopathy (PCV) is characterized
by the presence of aneurysmal polypoidal lesions in the
30 DOS Times - May-June 2019
Perspective
dynamic ICGA
4) Late Geographic Hyperfluorescence
(LGH) - Hyperfluorescent lesion
with clearly demarcated geographic
margin, which became apparent
approximately 10 min after the
injection of ICGA with a rosette-
pattern strongly support the
diagnosis of PCV (Figure 4)
Figure 2: Eye tracking showing polyp with BVN on ICGA and corresponding to it thumb like PED ICGA based classification of
(hyperreflectivity surrounded by hyporeflective lumen) with double layer sign (DLS) on SD OCT. PCV
Based on ICGA, PCV is classified in
following sub-types with relation to the
location of polyp / abnormal vascular
network (Figure 5)
1. Macular
a. Sub-foveal: Below the fovea
b. Juxta-foveal: Located within
1-199 µ from center of fovea
c. Extra-foveal: Location 200 µ or
more from center of fovea
2. Peri-papillary: Located with one disc
diameter from the margins of the
disc
3. Peripheral: Located outside the
arcade
Figure 3(a): Eye tracking ICGA with OCT showing polyp with BVN on ICGA and corresponding When to perform ICGA?
to polyp, thumb like polyp (TLP) seen on SD OCT; (b) SD OCT showing double layer sign i.e.
DLS, represented by two hyperreflective lines, inner signifying shallow RPE elevation and outer 1) Reddish orange sub-retinal nodules
signifying bruch’s membrane. 2) Sero-sanguineous maculopathy
3) Disproportionate amount of
exudation as compared to size of
lesion
4) Hemorrhagic PED / Spontaneous
submacular hemorrhage
5) Non-responsiveness to anti-VEGF
therapy15.
with subsequent late hypofluorescence Figure 4: ICGA showing presence of hyperflourescent lesion with demarcated geographic margin
surrounded by ring-like silhouette suggestive of late geographic hyperflourescence.
staining of Polyps.
PCV has been defined as “the
presence of single or multiple focal areas
of hyperfluorescence arising from the
choroidal circulation within the first 6
minutes after injection of ICGA, with or
without an associated BVN (Figure 3a).
The presence of orange red subretinal
nodules with corresponding ICGA
hyperfluorescence is pathognomonic of
PCV.
Additional ICGA features include:
1) Hypofluorescent halo around the
hyperfluorescent nodule
2) Branch Vascular Network (BVN):
Abnormal vascular network
appearing within 1 minute of dye
injection in the presence of feeder
vessel
3) Pulsatile filling of polyps seen on
Jain P. Pearls in Recognizing Polypoidal Choroidal Vasculopathy (PCV) www. dos-times.org 31
Perspective
Is fundus fluorescein
angiography (FFA) necessary?
FFA is used to identify presence
or absence of leakage from polyp and /
or abnormal vascular network. Hence
doing ICGA and FFA at baseline help us
to prognosticate the visual outcomes in
PCV16.
Figure 5: ICGA showing location of polyp (a) Subfoveal polyp; (b) Juxtafoveal polyp; (c) Extrafoveal On Optical Coherence
polyp; (d) peripapillary polyp. Tomography (OCT)
Figure 6: SD OCT shows typical features of PCV on OCT: (a) Notched PED; (b) Tall peaked PED;
(C) Xtra large PED; (D) Thumb like polyp i.e. TLP. Based on OCT, PCV can be suspected
if there is presence of any one of the
following features (Figure 6):
1) Thumb-like polyp (TLP) / Sharp
peaked PED: Denotes polyp
2) Notched PED: Signifies the
polypoidal lesion at margin of PED
3) Hyporeflective lumen surrounded
by hyperreflective ring attached to
undersurface of RPE
4) Double-layer sign (DLS): consists of
two hyperreflective layers of RPE and
bruch’s membrane. Inner layer is the
hyperreflective irregularly elevated
RPE and the outer layer is the inner
layer of the Bruch’s membrane. The
two layers are separated by a gap
and the extent of the DLS in SD-OCT
can be assessed with vertical and
horizontal section scan (Figure 3b)
5) Presence of normal / increased
choroidal thickness (Pachychoroid)
with pachy vessels on enhanced-
depth imaging OCT (EDI-OCT)
provides supportive evidence of PCV
and can be used to differentiate it
from AMD in which the choroid is
usually thin17-21.
Figure 7: 80 year old male with BCVA 20/40; [A,A1,A2] Fundus shows hemorrhage with SRF and Treatment
orange reddish nodule, ICGA shows juxta foveal polyp, OCT shows notched PED with SRF; [B,B1]
Intra vitreal Aflibercept monotherapy was given monthly for 3 months after which fundus shows Genetic studies suggest that PCV is
absorbtion of hemorrhage but SRF and orange reddish nodule persists, ICGA shows persistence of a type of choroidal neovascularization
polyp, OCT shows reduction in size of notched PED and SRF; [C,C1,C2] 6 months post combined (CNV), and other research has
PDT (Full fluence PDT with aflibercept) ICGA shows complete resolution of polyp, no disease demonstrated that the anti-VEGF
activity on OCT at last visit with flattening of PED and resolution of SRF. therapies used for AMD may improve
vision in patients with PCV. Yet, in
contrast to AMD, some PCV patients fail
to respond to anti-VEGF treatment and
do better with verteporfin photodynamic
therapy (PDT).
Recent studies indicate that
the combination of PDT and an anti-
VEGF agent provides added benefit in
treating PCV22. Combination therapy is
believed to be effective in the treatment
of PCV because anti-VEGF may work
synergistically with PDT in two ways:
Firstly, by targeting the two components
of PCV separately, combining its anti-
angiogenic effect on the exudation from
32 DOS Times - May-June 2019 Jain P. Pearls in Recognizing Polypoidal Choroidal Vasculopathy (PCV)
Perspective
Figure 8: 61 year female in whom four sitting of full-fluence combined PDT was done with follow I, Matsunaga H, Iwashita K, Nagai Y,
up of 96 months and on last visit no activity was observed with BCVA 20/20; [A,A1,A2] In 2009 et al. Idiopathic polypoidal choroidal
fundus shows SMD with exudates, ICGA shows polyp (arrow) and post PDT ICGA at 3 months vasculopathy in Japanese patients. Arch
shows resolution of polyp (A2); [B,B1,B2] In 2011 ICGA shows saccular dilatations in cluster Phthalmol 1999;117:1035-42.
(arrow) and post PDT shows regression of polypoidal network (B2); [C,C1-C4] In 2013 ICGA 13. Spaide RF, Yannuzzi LA, Slakter JS,
shows polypoidal network (white arrow) and thumb like polyp (asterisk) with SMD on OCT (C2). Sorenson J, Orlach DA. Indocyanine
Post PDT ICGA shows resolution of polyp (C3) and no SMD on OCT (C4); [D,D1-D3] In 2017 green videoangiography of idiopathic
polyp with BVN on ICGA (D1) and DLS with thumb like polyp on OCT (D2). Post PDT shows polypoidal choroidal vasculopathy. Retina
resolution of SMD on OCT (D3) 1995;15:100-10.
14. Koh A, Lee WK, Chen LJ, Chen SJ, Hashad
abnormal vascular networks with the vasculopathy: incidence, demographic Y, Kim H, et al. EVEREST study: efficacy
angio-occlusive effect of PDT on polyps, features, and clinical characteristics. Arch and safety of verteporfin photodynamic
and secondly by counteracting the Ophthalmol 2003;121:1392-6. therapy in combination with ranibizumab
upregulation of VEGF after PDT that 5. Maruko I, Iida T, Saito M, Nagayama D, Saito or alone versus ranibizumab monotherapy
results from choroidal hypoperfusion. K. Clinical characteristics of exudative age- in patients with symptomatic macular
related macular degeneration in Japanese polypoidal choroidal vasculopathy. Retina
Conclusion patients. Am J Ophthalmol 2007;144:15- 2012; 32:1453-64.
22. 15. Anantharaman G, Sheth J, Bhende M,
The modified evidence based 6. Lafaut BA, Leys AM, Snyers B, Rasquin F, De Narayanan R, Natarajan S, Rajendran A,
guidelines for management of PCV Laey JJ. Polypoidal choroidal vasculopathy et al. Polypoidal choroidal vasculopathy:
emphasizes the need for multi modal in Caucasians. Graefes Arch Clin Exp Pearls in diagnosis and management.
imaging which includes ICGA + FFA + OCT Ophthalmol 2000;238:752-9. Indian J Ophthalmol. 2018;66:896-908.
for diagnosis and monitoring of disease 7. Yannuzzi LA, Wong DW, Sforzolini BS, 16. Tan CS, Ngo WK, Lim LW, Lim TH. A novel
activity. The importance of multi modal GoldbaumM, Tang KC, Spaide RF, et al. classification of the vascular patterns
imaging in diagnosing PCV is crucial and Polypoidalchoroidal vasculopathy and of polypoidal choroidal vasculopathy
helps in identifying it timely. neovascularized age related macular and its relation to clinical outcomes. Br J
degeneration. Arch Ophthalmol Ophthalmol 2014;98:1528-33.
References 1999;117:1503-10. 17. Alshahrani ST, Al Shamsi HN, Kahtani
8. Scassellati-Sforzolini B, Mariotti C, Bryan ES, Ghazi NG. Spectral-domain optical
1. Yannuzzi LA, Sorenson J, Spaide RF, R, Yannuzzi LA, Giuliani M, Giovannini A. coherence tomography findings in
Lipson B. Idiopathic polypoidal choroidal Polypoidalchoroidal vasculopathy in Italy. polypoidal choroidal vasculopathy suggest
vasculopathy (IPCV). Retina 1990;10:1-8. Retina 2001;21:121-5. a type 1 neovascular growth pattern. Clin
9. Sho K, Takahashi K, Yamada H, Wada, Ophthalmol 2014;8:1689-95.
2. Byeon SH, Lee SC, Oh HS, Kim SS, Koh HJ, Nagai Y, Otsuji T, et al. Polypoidal choroidal 18. De Salvo G, Vaz-Pereira S, Keane PA, Tufail
Kwon OW. Incidence and clinical patterns vasculopathy: incidence, demographic A, Liew G. Sensitivity and specificity
of polypoidal choroidal vasculopathy features, and clinical characteristics. Arch of spectral-domain optical coherence
in Korean patients. Jpn J Ophthalmol Ophthalmol 2003;121:1392-96. tomography in detecting idiopathic
2008;52:57-62. 10. Cheung CM, Li X, Mathur R, Lee SY, Chan polypoidal choroidal vasculopathy. Am J
CM, Yeo I, et al. A prospective study of Ophthalmol 2014;158:1228-380.
3. Liu Y, Wen F, Huang S, Luo G, Yan H, Sun treatment patterns and 1-year outcome 19. Liu R, Li J, Li Z, Yu S, Yang Y, Yan H, et al.
Z, et al. Subtype lesions of neovascular of asian age-related macular degeneration Distinguishing polypoidal choroidal
age-related macular degeneration in and polypoidal choroidal vasculopathy. vasculopathy from typical neovascular
Chinese patients. Graefes Arch Clin Exp PLoS One 2014;9:e101057. age-related macular degeneration based
Ophthalmol 2007;245:1441-5. 11. Li Y, You QS, Wei WB, Xu J, Chen CX, Wang on spectral domain optical coherence
YX, et al. Polypoidal choroidal vasculopathy tomography. Retina 2016;36:778-86.
4. Sho K, Takahashi K, Yamada H, Wada M, in adult Chinese: the Beijing Eye Study. 20. Chung SE, Kang SW, Lee JH, Kim YT.
Nagai Y, Otsuji T, et al. Polypoidal choroidal Ophthalmology 2014;121:2290-1. Choroidal thickness in polypoidal
12. Uyama M, Matsubara T, Fukushima choroidal vasculopathy and exudative
age-related macular degeneration.
Ophthalmology 2011;118:840-5.
21. Jirarattanasopa P, Ooto S, Nakata I,
Tsujikawa A, Yamashiro K, Oishi A,
et al. Choroidal thickness, vascular
hyperpermeability, and complement factor
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polypoidal choroidal vasculopathy. Invest
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22. Jain P, Anantharaman G, Gopalakrishnan
M, Goyal A. Long-term efficacy and
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polypoidal choroidal vasculopathy. Indian
J Ophthalmol. 2018;66:1119-1127.
Correspondence to:
Dr. Prashant Jain
Consultant Vitreo Retina and Uvea,
ICARE Eye Hospital and Post Graduate
Institute, Noida, India
Jain P. Pearls in Recognizing Polypoidal Choroidal Vasculopathy (PCV) www. dos-times.org 33
Perspective
Vision Loss Following Pars Plana Vitrectomy
Dr. Supriya Arora MS, DNB, FICO, FAICO (Vitreoretina)1 Dr Neha Goel MS, DNB, FRCS (Glasg)2
1. Princess Margaret Hospital, Nassau New Province, Bahamas
2. Consultant Vitreo Retina and Uvea, ICARE Eye Hospital and Post Graduate Institute, Noida, India
In the last two decades, vitreoretinal surgeries have often resolve or evolve into well-circumscribed hypopigmented
experienced a revolutionary change. With the advent of lesions with varying degrees of pigment mottling. On fluorescein
newer technology, instrumentation and ever improving angiography (FA) the phototoxic lesion may be more evident
skills, vitreoretinal surgeons have mastered the so called as a focal, well-circumscribed lesion with increased overall
`untreatable’ cases. However despite anatomic success, transmission and areas of pigment blocking. In vitreoretinal
functional success is not always achieved and patient not surgery, phototoxicity has been reported most often following
necessarily satisfied. MH repair and macular epiretinal membrane (ERM) removal, in
When expected outcomes are not achieved, there may part because of the proximity of the fiberoptic endoilluminator
be three sets of causes – one may be the underlying severity to the macula in these cases5. With these issues in mind,
or chronicity of the retinal condition such as longstanding there are a number of steps the surgeon can take to limit the
macula involving retinal detachment (RD), chronic macular incidence of retinal phototoxicity such as limiting illumination
hole (MH), prior history of endophthalmitis or trauma. Second intensity to the minimum necessary for adequate visualization,
includes the well known and easily diagnosed causes of vision maintaining a reasonable distance between the endoilluminator
loss such as cataract, glaucoma, keratopathies, cystoid macular and the retinal surface and avoiding direct foveal illumination
edema (CME), vitreous haemorrhage and postoperative whenever possible. Finally, one must be cautious when adjusting
endophthalmitis. Third set includes the unanticipated causes of illumination strategy for video recording. Surgeons may be
visual loss which are often underdiagnosed. tempted to increase illumination to improve the recording, but
These causes may be classified as: should remain aware of the potential for phototoxicity.
1. Retinal toxicity
• Phototoxicity Chemical toxicity
• Chemical toxicity
o Dyes Dyes
o Vitreous substitutes
o Antibiotics The closure rates after primary vitrectomy for MH
2. Inadvertent retinal trauma : Dehydration injury improved significantly after the peeling of internal limiting
3. Retinal Ischemia membrane (ILM) was introduced. For better visualization of this
4. Optic neuropathy thin and transparent membrane, various dyes have been used.
• Non-arteritic anterior ischemic optic neuropathy ICG-guided chromovitrectomy initially gained worldwide
• Traumatic optic neuropathy popularity, and a large number of studies showed easier and
5. Intraocular gas expansion less traumatic ICG-guided peeling with good clinical results in
6. Anaesthesia related vision loss MH surgery. However, this popularity soon waned as the toxicity
profile of ICG became evident. Some clinical postoperative
Retinal toxicity side effects of ICG-assisted chromovitrectomy include RPE
defects, visual field defects and possible optic nerve atrophy6.
Phototoxicity Clinical data showed that ICG can remain intravitreally or can
deposit persistently on the optic disc after MH surgery.
Light-induced retinal injury may be photochemical, thermal ICG can also diffuse to the subretinal space through the MH,
or mechanical, all of which are dependent on spectral irradiance causing RPE damage. Based on histopathology studies, it
and duration of light exposure. Photochemical injury results has been hypothesized that the use of ICG may alter the
from prolonged cumulative exposure to light and subsequent cleavage plane for ILM removal causing it to occur deeper
formation of reactive oxygen species1,2. Thermal injury results to the inner surface of the ILM7. Several studies8 found less
from heat generated by higher-intensity light absorption, visual acuity improvement in ICG assisted ILM peeling as
primarily at the level of the retinal pigment epithelium (RPE), compared to those patients in whom ICG was not used. Trypan
with resultant tissue injury3. Thermal damage may play a role in Blue (TB) emerged as an alternative, however it does not stain
augmenting photochemical damage. Mechanical injury results ILM very well. It is recommended mainly for ERM staining9.
from plasma transients and resultant shock waves formed Many clinical studies reveal that TB exerted little or no toxic
by tissue absorption of short, ultrahigh energy laser pulses. effect to the retina10. Histological examination discloses that
Acutely, phototoxic retinal lesions may be undetectable or TB staining may produce retinal damage, especially at higher
may present as retinal edema with subtle retinal opacification, concentrations11. Brilliant Blue (BB) dye has brought about
typically within 24-48 hours4. Over time, phototoxic lesions a lot of enthusiasm as it appears to combine the best of both
34 DOS Times - May-June 2019 Arora S. et al.Vision Loss Following Pars Plana Vitrectomy
Perspective
Figure 1: (a) Fundus photograph of the right eye of a 25 year old male showing a retained PFCL include displacement of photoreceptor
bubble subretinally, superior to the macula. BCVA was 6/24. He had been operated for retinal nuclei into the outer segments, direct
detachment with giant retinal tear a month back and PFCL had been used intra-operatively. outer segment distortion, loss of the
Lasered retinotomy can be seen inferior to the optic disc. (b) One month later, BCVA dropped outer plexiform layer and atrophy of the
to 6/60 and fundus showed subfoveal migration of the retained PFCL bubble. (c) SD-OCT scan RPE layer13,15. Chemical toxicity of PFCLs
demonstrated a subfoveal hyporefelctive space corresponding to the PFCL bubble with thinning is likely related to their concentrations
of the overlying retinal layers. (d) Immediate subfoveal PFCL removal with silicon oil removal was of polar impurities, such as hydrogen16.
done. Post operatively, BCVA improved to 6/36. Fundus showed epiretinal membrane formation, A variety of strategies have been
which was confirmed on SD-OCT (e). employed to remove retained subretinal
PFCL, including clinic-based pneumatic
Figure 2: (a) Fundus photograph of the left eye of a 60 year old made operated for pseudophakic displacement and intraoperative
retinal detachment 3 months back. Silicon oil was in situ and the retina was attached. BCVA drainage with a variety of small caliber
was 6/18 (b) SD-OCT showing mild macular thinning with hyperreflectivity corresponding to the instruments17.
silicon oil meniscus. (c) Pattern ERG showed flattened waveform in the left eye compared to the
right (normal) eye. (d) Multifocal ERG of the right eye showed normal P1 amplitudes with a well Silicone oil
defined foveal peak while that of the left eye showed decreased P1 amplitudes with a flattened Although its use can lead to a variety
foveal peak (e).
of well-known complications in the
worlds : good staining capability and ease and choice of PFCL14. Dispersion into anterior segment, including cataract,
of use intraoperatively like ICG as well as small bubbles occurs at the PFCL- glaucoma and keratopathy, silicone
minimal toxicity and good postoperative vitreous interface and is characterized oil is generally well tolerated in the
outcome like TB12. by the formation of numerous small posterior segment18. Several clinicians
droplets that can migrate and affect in Europe have described unexpected
Perfluorocarbon Liquids optical clarity of the PFCL. In addition, central vision loss around the time of
Although generally recognized as trabecular obstruction may be caused by silicone oil removal19-21. Patients with
macrophages that have ingested these macula sparing RD undergoing silicone
being biologically inert for intraoperative small bubbles. The ocular toxicity of oil tamponade developed deep central
use, Perfluorocarbon Liquids (PFCLs) PFCLs is related to their chemical toxicity scotomata, often around the time of
may cause retinal toxicity and /or and mechanical effects on the retina. In oil removal. Evaluation and work -up,
mechanical trauma when used as a the rabbit eye, the high specific gravity including optical coherence tomography
prolonged vitreous substitute or when of PFCLs lead to mechanical compression (OCT) and FA, were unrevealing. In such
inadvertently retained in the subretinal of the dependent retina, which appears cases, multifocal electroretinogram (ERG)
space (Figure 1)13. Retention of PFCL is as loss of the outer plexiform layer. The demonstrated decreased central visual
likely dependent on surgical approach, later retinal changes seen after PFCL use response and pattern ERG indicated
the configuration of the detachment, pathology within the macula as opposed
to the optic nerve (Figure 2). Possible
etiologies include electrolyte shifts within
the vitreous cavity at the time of oil
removal leading to excitotoxicity within
the retina21, intraoperative phototoxicity,
especially in cases of combined
cataract extraction and oil removal;
environmental light phototoxicity during
silicone oil tamponade as the result
of poor short wavelength filtering by
silicone oil;22 and direct retinal toxicity.
Other more common causes of vision
loss after silicone oil removal, including
redetachment, CME, proliferation of ERM,
and hypotony, are ruled out with dilated
fundus examination and OCT.
Aminoglycoside Antibiotics
Intraocular use of aminoglycoside
antibiotics can cause macular infarction.
Affected patients may experience
profound, irreversible vision loss with
signs of retinal infarction, including cotton
wool spots, retinal edema, and arteriolar
attenuation23. FA reveals severe macular
nonperfusion. Iris neovascularization
and neovascular glaucoma may develop
in cases of extensive infarction24. The
Arora S. et al.Vision Loss Following Pars Plana Vitrectomy www. dos-times.org 35
Perspective
mechanism of damage is not well related to intraocular pressure fluctuation cataract extraction and intraocular
understood, but appears to be related to thereby decreasing perfusion pressure at lens implantation. Ophthalmology.
direct neuronal toxicity, with subsequent optic nerve head. 1983;90:945-51.
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postoperative endophthalmitis. Recently, steps during routine vitrectomy. Traction 6. Engelbrecht NE, Freeman J, Sternberg
a number of surgeons have independently along the optic nerve during separation of P Jr, et al. Retinal pigment epithelial
reported macular infarction from the posterior cortical vitreous may lead changes after macular hole surgery
periocular aminoglycoside in sutureless to axonal or capillary injury31. This can be with indocyanine green-assisted
vitrectomy. In these cases the antibiotic secondary to direct mechanical trauma internal limiting membrane peeling.
reportedly entered the vitreous cavity via from the instrument or from transmitted Am J Ophthalmol. 2002;133:89–94.
the unsutured sclerotomies26. Currently, shearing forces from high vacuum. 7. Hirata A, Inomata Y, Kawaji T, Tanihara
use of intraocular aminoglycoside Another possible cause of direct nerve H: Persistent subretinal indocyanine
antibiotics is not recommended. Fourth trauma is removal of residual optic disc green induces retinal pigment
generation cephalosporins, such as stalks during diabetic vitrectomy. Trauma epithelium atrophy. Am J Ophthalmol.
ceftazidime, are safe alternatives with to the retinal nerve fiber layer itself is a 2003;136:353-355.
broad Gram- negative coverage. potential cause of unexplained vision loss 8. Gass CA, Haritoglou C, Schaumberger
after ERM peeling32. M, Kampik A: Functional outcome of
Inadvertent retinal trauma: macular hole surgery with and without
Dehydration injury Intraocular Gas Expansion indocyanine green assisted peeling
of the internal limiting membrane.
Many patients with successfully Patients with intraocular gas are Graefes Arch Clin Exp Ophthalmol.
closed MH have focal visual field deficits, typically advised to avoid high-altitude 2003;241:716-720.
usually in the temporal periphery. The travel, as the lower barometric pressure 9. Rodrigues EB, Maia M, Meyer CH, et al.
most likely explanation for this field loss is leads to expansion of the intraocular Vital dyes for chromovitrectomy. Curr
mechanical damage or dehydration injury gas. Central retinal artery occlusion has Opin Ophthalmol. 2007;18(3):179-87.
to the retina during air-fluid exchange. resulted from expansion of intraocular 10. Perrier M, Sebag M. Trypan blue-
Welch et al demonstrated that the gas during air travel33. Nitrous oxide assisted peeling of the internal
location of the field defect changed with anesthesia should also be avoided in limiting membrane during macular
the location of the air infusion cannula27. patients with intraocular gas because of hole surgery. Am J Ophthalmol.
Another possible explanation for field loss potential expansion of the gas bubble. 2003;135(6):903-905.
in MH repair is mechanical trauma to the Nitrous oxide has low blood solubility 11. Uno F, Malerbi F, Maia M, et al.
optic nerve during peeling of the cortical and may enter the intraocular gas bubble Subretinal trypan blue migration
vitreous. Presently, peripheral visual field rapidly34. during epiretinal membrane peeling.
loss is an uncommon complication of MH Retina. 2006;26(2):237-239.
surgery, with an incidence of less than Anaesthesia related vision loss 12. Shukla D, Kalliath J, Neelakantan N,
1% in one series28. This may be due to et al. A comparison of Brilliant Blue
improved surgical technique with shorter Retrobulbar injection can lead to G, Trypan Blue, and Indocyanine
surgical times, reduction of air-infusion optic neuropathy by both direct trauma Green dyes to assist internal limiting
pressure below 35 mm Hg, and the use of and secondary ischemia35. Retrobulbar membrane peeling during macular hole
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of retrobulbar anesthesia, may cause 13. Eckardt C, Nicolai U, Winter M,
Retinal Ischemia an orbital compartment syndrome with et al. Experimental intraocular
subsequent ischemic damage to the optic tolerance to liquid perfluorooctane
Case reports29,30 of central or branch nerve. Similarly, inadvertent injection and perfluoropolyether. Retina.
retinal vessel occlusion are there after of anesthetic into the nerve sheath and 1991;11:375-84.
vitrectomy but even in the absence of a secondary nerve sheath hemorrhage may 14. Scott IU, Murray TG, Flynn HW Jr.,
large vessel occlusion, vitrectomy may produce damage. et al. Outcomes and complications
have visually significant permanent associated with perfluoro-n-octane
effects on intraocular hemodynamics. References and perfluoroperhydrophenanthrene
Eyes with advanced microvascular in complex retinal detachment repair.
disease may be particularly susceptible 1. Noell WK, Walker VS, Kang BS, et al. Ophthalmology. 2000;107:860—5.
to reductions in perfusion, leading to Retinal damage by light in rats. Invest 15. Conway MD, Peyman GA, Karacorlu M, et
worsening of macular ischemia. Ophthalmol. 1966;5:450-73. al. Perfluorooctylbromide as a vitreous
substitute in nonhuman primates. Int
Non-Arteritic anterior ischemic 2. Noell WK. Possible mechanisms Ophthalmol. 1993;17:259-264.
optic neuropathy of photoreceptor damage by light 16. Keese C, Giaver I. Cell growth on
in mammalian eyes. Vision Res. liquid interfaces: role of surface active
Non-arteritic anterior ischemic 1980;20:1163-71. compounds. Proc Natl Acad Sci USA
optic neuropathy (NAION) appears to 1983;80:5622.
occur with greater frequency following 3. Marshall J. Thermal and mechanical 17. Lai JC, Postel EA, McCuen BW 2nd
intraocular surgery which could be mechanisms in laser damage to the 2nd. Recovery of visual function
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4. McDonald HR, Irvine AR. Light- 18. Gallemore RP, McCuen BW 2nd. Silicone
induced maculopathy from the oil in vitreoretinal surgery, in Ryan SJ
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PA, Mosby; ed 4 2006, pg 2211—34.
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Perspective
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Am J Ophthalmol. 1997;124:698—9. Visual loss after use of nitrous oxide gas
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of silicone oil. Retina. 2004;24:871—7. al. Peripheral visual field defects after days after vitrectomy. Anesthesiology.
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treated with vitrectomy and intravitreal Nassau New Province, Bahamas
gentamicin. Arch Ophthalmol. 30. Verma L, Venkatesh P, Tewari HK.
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central retinal vein occlusion following
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Unexplained vision loss following
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1.
Arora S. et al.Vision Loss Following Pars Plana Vitrectomy www. dos-times.org 37
Recent Trends and Advances
OCT Angiography- Current Applications
Dr. Daraius Shroff MS, FRCS, Dr. Priyanka Gupta, Dr. Charu Gupta, Dr. Cyrus Shroff
Shroff Eye Centre, A -9 Kailash Colony, New Delhi, India
Abstract: Optical coherence tomography angiography (OCT-A) is a novel non-invasive three dimensional imaging technique for
visualizing the retinal vasculature and choroidal vascular layers in the macular area. Retinal diseases are a major cause of impaired
vision especially in the ageing population, hence is not surprising that advances in retinal imaging and the treatment of retinal diseases
are an active area of research. However, as with any new imaging technique OCTA has several inherent imitations. It is also important to
know and understand these along with their implications. In this article we will emphasised on the current applications of OCT-A in retinal
pathologies and how it has become an important tool in our armamentarium.
Key words: Optical coherence tomography angiography (OCT-A), Swept source OCT(SS), Wide field imaging.
OCT-A is a non-invasive imaging technique, choroid (Figure 1).
allows for simultaneous in vivo imaging of
the morphology as well as the vasculature of Evolution in OCT-A
retina. It facilitates visualization of the retinal
microvasculature and simultaneously allows Retinal imaging is changing rapidly. With the advent of
high-resolution enface and depth resolved OCT-A new understandings have emerged in retinal pathologies,
imaging. It was first adapted from OCT and is approved by the but as the progress and evolution goes on, so in OCT-A, there are
Food and Drug Administration (FDA) in 20151. OCT-A provides rapid changes occurring both in hardware in terms of increased
structural and potentially functional information regarding the scan speeds and a major or significant introduction of Swept
superficial and deep retina, as well as choroidal vasculature. source (SS) OCT. Swept –source OCT (SS) provides an additional
advantage with the upgraded automatic software providing a
OCT-A of a Normal Eye beautiful montage view with a much larger field of view.
Most of the OCT-A machines have standard scanning Current Applications & Interpretations of
patterns – 2x2, 3x3, 6x6, 8x8 and some of the newer ones OCT-A
to 12x12. For each of the scan pattern, B-scan and en face
structural images are generated along with three dimensional Various studies, so far have described the potential efficacy
microvascular maps of the retinal and choroidal circulation. of OCT-A in the evaluation of common retinal diseases such
The instrument provides settings for default en face images but as AMD, Diabetic retinopathy, Vascular Occlusions. However
boundary layers can be manually manipulated to study the exact Idiopathic juxta foveal telangiectasia (IJT), pachychoroid
area of interest. There are three distinct layers in the retina: spectrum, vascular disorders and para acute middle
superficial, deep plexus and outer plexus, choriocapillaries and maculopathy, adult vitelliform maculoapathy, and wide field
Figure 1: Normal OCT-A scan showing Superficial capillary plexus (Top left), deep capillary plexus, Avascular layer & choriocapillaries. Bottom left
showing fundus photo & corresponding OCT B scan.
38 DOS Times - May-June 2019 Venkatesh R. et al. Multicolor Imaging in Retinal and Choroidal Diseases
Recent Trends and Advances
1 (Figure 2). In grade 2 there is dilation
and enlargement of the vessels with
large intervascular spaces, telangiectatic
vessels, reduction and/or loss of
capillary density in both superficial and
deep capillary plexus (Figure 3). As the
disease progresses dilated anastomoses
form between the superficial and deep
plexuses and vascular invasion of the
FAZ occurs, grade 3 (Figure 4). In some
patients, the anastomoses between
the plexuses progresses to subretinal
neovascularisation, with connections to
the choroidal vasculature,grade 4 (Figure
5).
The above OCT-A classification is
according to Nalci H etal2.
OCT-A in Pachychoroid
diseases
Pachychoroid spectrum is a group
of macular diseases that manifest
similar choroidal findings – thickened
choroid with dilated choroidal vessels.
Central serous Chorioretinopathy (CSC),
pachychoroid pigment epitheliopathy,
Figure 2: Grade 1 IJT. Panel A shows normal superficial plexus and panel B shows telangiectatic pachychoroid neovasculopathy, and
peri foveal temporal capillaries in deep capillary plexus. Panel C showing corresponding Oct
Figure 3: Grade 2 IJT. Panel A shows mild teliengiectatic capillaries in superficial plexus and panel Polypoidal choroidal vasculopathy (PCV)
B shows marked changes in deep capillary plexus. Panel C shows corresponding OCT.
are entities of the pachychoroid clinical
spectrum. Diagnosis of Pachychoroid
neovasculopathy and PCV are helped by
OCT-A.
Pachychoroid neovasculopathy
(PNV) is distinguished from
neovascular AMD by several features,
including younger age at onset of
neovascularization, a relative absence
of drusen, and a thick choroid with
pachyvessels. In pachychoroid
neovasculopathy, neovascularization is
most commonly Type 1 (Sub RPE) and is
best evaluated with OCT-A.
The usefulness of OCTA is well
exemplified in a 64-year-old gentleman
who received multiple ranibizumab
injections for a provisional diagnosis of
subretinal fluid (SRF) with suspected
CNVM.
FFA (Figure 6 and b) and ICG
(Figure 6 c and d) was done. However,
the diagnosis could not be ascertained
until OCTA revealed a classic vascular
network (Figure 7 a and b). Enhanced
depth imaging (EDI) confirmed thickened
choroid suggestive of pachychoroid
spectrum (Figure 7c). Subsequent
treatment with aflibercept resulted in
resolution of fluid and improvement in
vision.
OCT-A are the recent areas of interest in 2) is a neurodegenerative disease of the OCT-A in Adult onset fovelo
the imaging armamentarium. macular area that affects all microvascular macular vitelli form
layers of the retina. The earliest changes dystrophy
OCT-A in Idiopathic on OCT-A in MacTel are seen on the
Juxtafoveal Telangiectasia temporal aspect of the parafoveal deep Patients with vitelliform dystrophy
capillary plexus and normal superficial have slow progressive vision loss.
Idiopathic Juxtafoveal Telangiectasia capillary network, classified as grade However, CNVM may occur in a few case
or Macular Telangiectasia Type 2 (MacTel and can remain undetected. OCT-A allows
Venkatesh R. et al. Multicolor Imaging in Retinal and Choroidal Diseases www. dos-times.org 39
Recent Trends and Advances
technology, we are able to accurately put
together images from different quadrants.
This is done by an automatic software
thereby providing a beautiful montage
view (Figure 9) with a much larger field
of view. This enables us to image areas
of neovascularization as well as capillary
non perfusion non-invasively. It is also
possible to analyse vascular changes
at varying depths. Wide field imaging
is particularly important in diabetic
retinopathy, vascular occlusions and
peripheral vascular conditions. This is
specially important in patients with renal
dysfunctions where dye angiography may
be contraindicated.
Figure 4: Grade 3 IJT. Panel A &B shows marked vascular changes with FAZ irregularity. Panel C OCTA in follow up and and
shows vascular invasion. Panel D shows corresponding OCT. monitoring of therapy
It provides qualitative
Figure 5: Grade 4 IJT. Image shows SRNVM at Figure 6: Panel A and B – FFA (arteriovenous phase) shows stippled hyperfluoroscence in both
avascular zone with corresponding OCT. eyes. Panel C and D – ICG angiography shows dilated choroidal vessels in both eyes no definite
CNVM can be delineated.
to look at vascular abnormalities that other imaging techniques for eyes with quantitative information regarding
possibly occur in the different stages of retinal artery occlusion (RAO), thus, it can choroidal neovascularisation (CNV) flow,
AFVD and the potential importance in reveal deficiencies involving acute and vessel density and lesion area. OCTA
assessing the presence of CNV masked chronic flow interruption in RAO which can be used as a tool for monitoring the
by the vitelliform material (Figure 8). is well documented in various studies. response to anti-VEGF therapy (Figure
Lupidi et al3 in their study showed high There is an important and sometimes 10) and its progression and regression
sensitivity and specificity of CNV detection undiagnosed entity called para acute pattern. Thereby it allows classification
on OCT-A in cases of AFVD. K Joshi et middle maculopathy (PAMM). This is of new vessels, highlighting their
al4 have studied features on OCT-A but an OCT finding where band-like hyper morphology6. It can also be useful to see
the unifying characteristic was the lack reflectivity at the level of the inner nuclear post laser regression of NVE in diabetic
of visualization of the choriocapillaries layer is seen5. Unique ability of OCT-A retinopathy7.
under the vitelli form lesion in 100% of to differentiate laminar focal capillary
the patients for which they hypothesize defects that maybe undetected by FFA is Conclusion
that there can be blockage of flow signals a potential significant advantage.
by the vitelli form material. OCT-A is a budding potential
Wide field imaging with OCTA technology and is providing inset into
OCT-A in PAMM Montage images better understandings. However as with
other imaging technologies it has its own
OCT-A may have advantages over By using this advanced swept-source limitations and requires one to spend
40 DOS Times - May-June 2019 Venkatesh R. et al. Multicolor Imaging in Retinal and Choroidal Diseases
Recent Trends and Advances
Figure 7: OCTA at the level of choriocapillaries. Panel A shows small
vascular network suggesting CNVM temporal to fovea in the right eye.
Panel B shows the vascular network with central void area in the left
eye. Panel C - EDI OCT shows increased choroidal thickness with
persistence of SRF in the right eye.
Figure 8: OCTA showing vascular network with corresponding OCT
showing vitelliform dystrophy with cystic spaces.
Figure 9: Montage OCTA image (panel A) showing gross non perfusion
in all quadrants with active NVE (arrow). Panel B showing FFA showing
leaking NVE and non-perfusion.
time in its interpretation. Due to advancements, the accurate Figure 10: OCTA image (panel A) shows small vascular network
diagnosis and localization of a variety of pathologies will in turn depicting CNVM (red circle) Pre Anti VEGF therapy. Corresponding
alter the management and clinical outcomes of the treatment of B scan OCT shows CNV with small cystic space and. Panel B shows
retinal diseases favourably. regression of network following anti-VEGF therapy. Corresponding B
scan OCT also shows regression of CNV with resolution of cystic space.
References dystrophy: pearls and pitfalls. Invest neovascularization: An optical
Ophthalmol Vis Sci 2015; 56:7638–45. coherence tomography angiography
1. Huang Y, Zhang Q, Thorell MR, An L, 4. J o s h i K M , N e s p e r P L , F a w z i A A , M i r z a study.IJO;2018;16:1855-56.
RG.Optical coherence tomography
Durbin MK, Laron M, et al. Swept- angiography in adult onset Correspondence to:
foveomacular vitelliform dystrophy. Dr. Daraius Shroff
source OCT angiography of the Retina.2018 ;38:600-605. Shroff Eye Centre,
5. ChristenburyJG, Klufas,MA,. Sauer TC, A -9 Kailash Colony,
retinal vasculature using intensity Sarraf D,OCT Angiography New Delhi, India
of Paracentral Acute Middle Maculopathy
differentiation-based optical Associated With Central Retinal Artery
Occlusion and Deep Capillary Ischemia.
microangiography algorithms. Retina 2015;46:579-81.
6. Coscas et al. OCT Angiography in
Ophthalmic Surg Lasers Imaging exudative AMD. Retina; 2015; 35:2219-
28
Retina. 2014;45(5):382–389. 7. Shroff D,Gupta P, Gupta c, Shroff,C.
2. Hilal Nalcı, Figen Şermet, Sibel Post-laser regression of diabetic
Demirel, Emin Özmert. Optic
Coherence Angiography Findings in
Type-2 Macular Telangiectasia. Turk J
Ophthalmol. 2017 Oct; 47(5): 279–284.
3. Lupidi M, Coscas G, Cagini C, et al. Optical
coherence tomography angiography
of a choroidal neovascularization in
adult onset foveomacular vitelliform
Venkatesh R. et al. Multicolor Imaging in Retinal and Choroidal Diseases www. dos-times.org 41
Recent Trends and Advances
Multicolor Imaging in Retinal and Choroidal Diseases
Dr. Ramesh Venkatesh MS, Dr. Sabitabh Kumar MS, Dr. Naresh Kumar Yadav DO, FRCS
Department of Retina and Vitreous, Narayana Nethralaya, Chord Road, Rajaji Nagar, Bengaluru, India
In 1980, the scanning laser ophthalmoscope (SLO) was Figure 1: Multicolor imaging of a normal fundus.
initially described as the ‘flying spot TV ophthalmoscope’1.
A single point of laser light at a specified wavelength was neovascular AMD in high-risk patients with early or intermediate
scanned across the retina in a series of parallel lines AMD. Reticular pseudo drusen a feature that is associated with
and enabled an alternative method of capturing fundus all stages of AMD that may represent a high-risk phenotypic
images2,3. Compared to standard fundus cameras, images feature for progression, can also be imaged more distinctly
produced by the SLO have a higher resolution and image quality on multicolor imaging6-8. On multicolor imaging, the reticular
due to reduced light scatter. In addition, confocal SLO (cSLO) pseudo drusen appears as a central hyper reflective lesion with
systems allow image acquisition at different planes and higher a hypo reflective border. The boundaries of geographic atrophy
contrast due to suppression of scatter light. Furthermore, (GA) are more clearly demarcated on the multicolor images
images can be acquired through an undilated pupil. than in the CFP. However, to determine foveal sparing, SD-OCT
The so-called ‘multicolor’ mode developed for the was superior compared to the other imaging modalities9.
SPECTRALIS Optical Coherence Tomography SDOCT
(SPECTRALIS SD-OCT, Heidelberg Engineering, Heidelberg, Polypoidal choroidal vasculopathy (PCV)
Germany) is based on the principle of multispectral imaging.
The scanning protocols routine used to obtain the images are The PCV lesion on CFP appears as an orange-red nodule.
the 30° and 55° protocols. It uses the cSLO to capture three In contrast, the PCV lesion is darker red with a greenish tinge
simultaneous reflectance images using three monochromatic on multicolor imaging. This is likely due to the PCV lesion being
laser sources: (1) blue reflectance (BR; 488 nm), (2) green located deep under the retinal pigment epithelium in contrast
reflectance (GR; 515 nm) and (3) infrared reflectance (IR; to more superficial subretinal bleeding, which appeared red.
820 nm). These different wavelengths of light penetrate the Hence, the multicolor imaging may have the added advantage of
retinal surfaces at different depths to demonstrate details at being able to distinguish hemorrhages in different layers of the
the various layers of the retina. The BR particularly enables retina when compared to CFP, although this finding will need
details of the inner retina and the vitreoretinal interface such to be verified in larger studies. The more distinct border seen
as epiretinal membranes, retinal nerve fiber layer thinning and on the multicolor image shows a correlation with the loss of
macular pigment changes. GR images specifically allow deeper the photoreceptor layer seen on SD-OCT. None of these features
details such as retinal blood vessels and intraretinal lipid could be clearly distinguished in CFP. Also, in contrast to the
exudation to be seen. IR predominantly visualizes structures area of leakage seen on fundus fluorescein angiography and
at the level of the outer retina and choroid including drusen indocyanine green angiography, the abnormal area imaged on
and retinal pigmentary epithelium alterations (Figure 1)4,5. both multicolor imaging and FAF is larger. This finding has been
With this background, we describe the clinical use and imaging reported in previous studies suggesting that the structural
features of multicolor imaging in a variety of retinal and retinal damage seen on FAF and IR imaging may extend beyond
choroidal diseases, predominantly at the macula. In particular, the boundaries of the leakage in the PCV lesion10,11.
multicolor imaging was compared with conventional CFP
addressing differences in appearance. Other multimodal forms Diabetic Eye Disease
of imaging available were correlated to features seen on these
multicolor images where applicable. Diabetic Eye Disease Screening and early detection of
diabetic eye disease to prevent vision loss is beneficial to both
CLINICAL APPLICATION the individual patient and their community12. A recent study
using wide-field imaging and OCT showed improvements in
The main advantage of the multicolor image is the the detection rates of higher grades of diabetic retinopathy
improved visualization of the optic disc, retinal vessels and
even the larger choroidal vessels. The contrast of the optic
disc cup is more distinct compared to the CFP, which may have
potential for future applications in glaucoma.
Age-Related Macular Degeneration (ARMD)
Improved imaging techniques in the context of ARMD
has allowed earlier detection of the disease and treatment as
well as monitoring during anti-VEGF therapy. In particular,
the detection of retinal hemorrhages is an important sign of
42 DOS Times - May-June 2019 Venkatesh R. et al. Multicolor Imaging in Retinal and Choroidal Diseases
Recent Trends and Advances
compared to clinical examination13. From Figure 2: Multicolor imaging in wet ARMD.
the ophthalmologist perspective, an Figure 3: Multicolor imaging in patient with diabetic retinopathy and macular edema.
advantage of the multicolor imaging on
the combined cSLO + SD-OCT platform
is that a single device can perform all
imaging modalities required. Patients can
benefit from a one-stop service, and this
may mean time saved and improved cost-
effectiveness for the practice. In addition,
cSLO imaging can also be performed in
an undilated pupil. Multicolor imaging
in combination with SD-OCT has the
potential to improve detection rates of
diabetic eye screening programs, and
further studies should be performed to
evaluate this further. These features were
imaged more clearly on the multicolor
image than the CFP. Diabetic macular
edema (DME) as a complication of
diabetic retinopathy is difficult to detect
on CFP during screening in the absence
of hard exudation14,15. Multicolor imaging
with superior resolution may be an
alternative to improve the detection rates
of DME (Figure 2). The 55° multicolor
image enables documentation of the
status of the diabetic retinopathy, and
the 30° image allows closer details to
be seen such as a sclerosed vessel along
the inferior arcade. However, potential
challenges for detecting DME on
multicolor images could include ‘ghost’
maculopathy artifacts and poor optical
media.
Retinal Vascular Occlusion Figure 4: Multicolor imaging in a patient with superotemporal branch retinal vein occlusion in
the left eye.
Retinal vascular occlusions
can cause visual impairment when Figure 5: Multicolor imaging in a case with acute central serous chorioretinopathy.
complicated by macular edema and
neovascularization16,17. Close monitoring shows the most similarities to clinical the CSCR and the multifocal areas of
of this disease and the detection of examination. However, the clinician neurosensory detachments are seen
complications early allows treatment may need to appreciate that the exact more distinctly on multicolor imaging
to prevent vision loss. Fundus imaging color may differ from what is observed than CFP. Previous studies have reported
allows the accurate documentation of clinically on multicolor imaging reduction of macula function as a result
disease progression and the response to of chronic CSCR due to degenerative and
treatment. Other Acquired Macular Diseases atrophic changes20-22. Multicolor imaging,
in addition to IR and FAF imaging may
The quality of the CFP is superior Acute central serous be useful to detect subtle changes in
to the multicolor image demonstrating the retinal structure which may not be
features such as collateral and sclerosed chorioretinopathy (CSCR) is clinically apparent after the resolution
vessels. The artifact on the multicolor of the subretinal fluid from CSCR. The
image obscured the collateral vessels. characterized by the serous detachments appearance of epiretinal membranes
However, the area of neovascularization
was seen clearly in both modalities. The of the neurosensory retina associated
appearance of a branch retinal artery
occlusion is seen on CFP and multicolor with the area of focal pigment epithelial
imaging. The boundary of the intraretinal
thickening is seen on both the CFP and detachments18,19. The boundaries of
the multicolor image. The appearance
on the multicolor image had a greenish
tinge versus the pale area seen on
the CFP. When compared to clinical
ophthalmoscopic examination, the CFP
Venkatesh R. et al. Multicolor Imaging in Retinal and Choroidal Diseases www. dos-times.org 43
Recent Trends and Advances
Figure 6: Multicolor imaging in a case with parafoveal telengectesia. of different lens attachments, there
is the option of taking 55° images to
Figure 7: Multicolor imaging in a case with blunt trauma following shuttle cock injury. capture more peripheral changes. The
multimodal single device may have an
on CFP and multicolor imaging are correlates better with FAF imaging advantage to save time in high-volume
compared. Multicolor imaging can also than the CFP. This helps to distinguish clinics and may also be an advantage
be used to identify the early stages of the area of foveal sparing as confirmed in smaller ophthalmic practices where
macular telangiectasias. on OCT imaging to help explain why cost and space restraints only allow for
despite central atrophy causing a central limited imaging equipment.
Inherited Retinal Dystrophies scotoma, visual acuity is still preserved.
Comparing CFP to multicolor imaging, Compared to CFP, which requires
Inherited retinal diseases are a pigmented lesions such as choroidal a bright flash of light to capture images,
heterogeneous group of conditions that nevus and choroidal melanomas show single-wavelength small laser spots are
are responsible for visual impairment a varying degree of color when imaged used in multicolor imaging, which may
in young patients. Limited treatment by multicolor imaging. The depth of the cause less photophobia. Nonmydriatic
options for these diseases exist, and lesion, the degree of pigmentation and multicolor imaging in combination with
imaging is useful for diagnosis, prognosis surrounding changes like blood, fluid OCT may be considered for use in future
and monitoring the progression of or atrophy all influence the appearance screening programs following validation
the disease. Secondary choroidal of lesion on multicolor imaging. In the studies to improve the accuracy of
neovascularization (CNV) development case of choroidal rupture due to ocular screening for diseases such as diabetic
is a common complication picked up on trauma, areas of atrophy and rupture can retinopathy and AMD.
multicolor imaging. Early detection of be clearly imaged with both modalities;
CNV allows treatment with anti-VEGF however, the areas of pigmentation also Also, the three reflectance images
injections that can stabilize vision and show a variation in color. that make up the multicolor image can
prevent further deterioration23. The be viewed separately to enable the detail
angioid streak was best seen on FAF DISCUSSION at each level to be imaged if required.
and was less distinct on both CFP and Retinal atrophy imaged with multicolor
multicolor imaging. Stargardt disease is a Multicolor imaging available for use images shows good correlation with FAF
type of macular dystrophy characterized on the combined cSLO + SD-OCT platform images, and this may be an advantage
by bilateral white yellowish deep retinal has the advantage of enabling fundus over CFP for certain diseases such as GA
lesions (flecks) seen in the posterior images to be taken with a single device and macular dystrophies.
pole which can extend to the mid- without the need for an additional color
periphery with progression to a loss fundus camera. Current systems of multicolor
of the foveal reflex, granulation in the imaging, however, have some
retinal pigmentary epithelium and This combined platform can also disadvantages when compared to
macular atrophy24-26. In both CFP and be used to take multimodal images conventional CFP. Multicolor imaging
multicolor imaging, the white flecks of such as FAF, infra-red imaging, spectral- may require a slightly longer period
the fundus can be seen. The demarcation domain optical coherence tomography, of fixation to take the three separate
of the central area of atrophy is more fluorescein and indocyanine green images compared to CFP. Artifacts must
clearly seen on multicolor imaging and angiography. In addition, with the use be considered. Also, conventional CFP is
very comparable to clinical examination
findings, while on multicolor images
there are variations of the color produced
compared to the clinical examination
especially in cases of pigmentary lesions.
Ophthalmologists need to be mindful
of these differences when interpreting
the multicolor images.
In summary, multicolor imaging
has many clinical applications, and
in some cases may be used to replace
conventional CFP. As the use of multicolor
imaging becomes more widespread,
further studies will need to validate the
retinal details seen on multicolor imaging
with conventional CFP and other imaging
modalities.
Reference
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Recent Trends and Advances
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Venkatesh R. et al. Multicolor Imaging in Retinal and Choroidal Diseases www. dos-times.org 45
Techniques
Double HandshakeTechnique:ModifiedTechnique for
Removal of Retained Metallic Intraocular Foreign Bodies
Dr. Vinod Kumar MS, DNB, MNAMS, FRCS(Glasg), Dr. Mayank Bansal MD, Dr. Brijesh Takkar MD, DNB
Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
Abstract: Purpose: To describe a modified technique for removal of magnetic intra-ocular foreign bodies (IOFB) using 25-gauge
vitrectomy system. Technique Prospective interventional study. Following standard 25-gauge vitrectomy, one scleral port was enlarged
to introduce a 20-gauge intra-ocular magnet, and the IOFB was levitated to anterior vitreous cavity. A 25-gauge end grasping forceps
was then introduced through the non-dominant port to grip the IOFB, performing the first handshake. Another end grasping forceps was
then introduced through the enlarged dominant scleral port to re grasp the IOFB, thus performing the second handshake. The IOFB was
then externalized.
Result: Five eyes of 5 patients were operated with this technique. All patients were phakic with clear lens and Zone 2/3 penetrating
injury. Mean decimal visual acuity increased from 0.44 at baseline to 0.77 at 6 months of follow up. Visual acuity remained stable or
improved in all the patients. No serious complications occurred due to the technique.
Conclusion: Double handshake technique allows safe removal of foreign bodies without the enlargement of both the scleral ports.
Keywords: 25 gauge vitrectomy, Intra-ocular foreign body, Intra-ocular magnet, Handshake technique.
Metallic foreign bodies especially those of retained magnetic IOFBs undergoing 25-gauge vitrectomy were
iron if left inside the eye for long can lead included in the study. The patients with retinal detachment, non-
to siderosis bulbi and severe irreversible metallic IOFBs and requiring simultaneous lens management
visual loss. The management of such IOFBs were not included. Baseline characteristics were recorded, and
particularly if retained in posterior segment clinical examination, X-Ray findings and ultrasound imaging
consists of safe removal using pars plana were used to judge the size and location of IOFB in all the cases
vitrectomy. The removal of posterior segment IOFBs however prior to surgery. The surgical procedure was explained to all the
poses significant challenges for vitreo-retinal surgeons. patients and an informed consent was taken. The study adheres
These include increased chances of retinal detachment, to the institutional guidelines and declarations of Helsinki.
endophthalmitis and proliferative vitreoretinopathy1.
Since the introduction of minimally invasive vitreous Technique
surgery (MIVS), its use has increased tremendously and is now
the accepted modality for even complex vitreo-retinal cases2. All the eyes underwent 25-gauge PPV using a trans-
This is because of several advantages offered by MIVS that conjunctival approach on Constellation Vision System (Alcon,
include lesser retinal mobility, easy and precise manipulation of Fort Worth, TX) under peribulbar anaesthesia by a single
tissues, improved wound anatomy and reduced postoperative surgeon (VK). Posterior vitreous detachment (PVD) was
pain and inflammation3. induced using Triamcinolone Acetonide crystals and vitreous
Development of intraocular forceps and magnets has lead was removed with special emphasis on clearing all vitreous
to better outcomes in posterior segment IOFBs: the later is attachments from the foreign body. Following this, the dominant
especially useful in lifting the metallic IOFB from the retinal hand superior sclerotomy port was enlarged using 20-gauge
surface. This becomes crucial in the presence of attached MVR knife. A 20-gauge rare earth intraocular magnet was used
healthy retina since no counter-traction is required with to lift the foreign body off the surface of retina (Figure 1a). The
magnet to lift the foreign body of the retinal surface as opposed IOFB was brought to anterior vitreous (Figure 1b) and using
to that of forceps. While 25-gauge MIVS has been reported the non-dominant hand, grasped with a 25 gauge end-grasping
for the removal of posterior segment foreign bodies, both forceps (first handshake, Figure 1c). Another intra-vitreal
scleral ports often need to be enlarged for the introduction of end-grasping forceps was then used to grasp the IOFB (second
intraocular magnet/forceps and retrieval of IOFB. In this article, handshake, Figure 1d)) and bring out through the enlarged port
we describe a modified technique by which metallic posterior (Figure 1e, f, see Video, Supplemental Digital Content 1, which
segment IOFB can be removed using intra-ocular magnet, and demonstrates double handshake technique of foreign body
without the need to enlarge both the scleral ports. removal). Air-fluid exchange was done and the enlarged scleral
port was sutured with 7-0-vicryl sutures. Thorough retinal
Methods peripheral examination was done to rule out retinal breaks. The
other two ports were closed and sclerotomies were massaged
All the surgeries were conducted at a tertiary eye care to prevent any leak. The patients were prescribed standard
center in Northern India by a single surgeon (VK). Patients with postoperative treatment consisting of topical antibiotic, steroid
46 DOS Times - May-June 2019 Kumar V. et al. Double Handshake Technique...
Techniques
to best-corrected visual acuity (BCVA,
Snellens), intraocular pressure (IOP)
and detailed ocular examination. All
patients were followed up for minimum
of 6 months. Primary outcome measure
was final best-corrected visual acuity.
Complications, if any, were recorded
during the follow up period.
Figure 1: Figure depicting the surgical technique. (A) The metallic foreign body is ‘gripped’ with Results
the intra-ocular magnet. (B) The magnet-foreign body complex is levitated to the anterior vitreous
cavity. (C) The first handshake: A 25 G end grasping forceps is used to grip the foreign body Mean age of the patients was 24.4
through the non-dominant scleral port. (D&E) The second handshake: Another end grasping years and all were male. The ocular
forceps is introduced through the dominant-sclerotomy and the foreign body is gripped in the penetration in all the cases was due
manner most convenient for externalization. (F) The foreign body is externalized through the to hammer-chisel mechanism. These
dominant scleral port. patients had Zone 2/3 injury with clear
crystalline lens. Cases 1-4 presented
within the first week of injury, while
case 5 presented 1 month later. Case 5
had been previously operated for scleral
wound repair. Case 3 required repair of
the primary wound at the time of surgery,
while the rest had self sealed entry
wounds. The IOFB was removed within 7
days of presentation to us in all the cases.
The baseline patient characteristics,
surgical notes, patient outcomes and
complications have been presented in
(Table 1). The mean visual acuity at
baseline was 0.44 decimal units and
improved to 0.77 decimal units in all
the cases. The IOFB was not lost from
grip in any case. No patient reported
deterioration in visual acuity. No serious
complications occurred due to the
Table 1: Demographic details, surgical notes and visual outcomes in five patients with foreign body operated with double
handshake technique.
Age (yrs) Baseline Surgical notes Final visual Complications
acuity*,#
visual acuity*
Case 1 23 0.02 Vitreous hemorrhage present. 1.8mm FB in 0.5 Postoperative ERM
vitreous cavity.
Case 2 16 0.02 Vitreous hemorrhage present, 1.1mm FB 0.67 None
incarcerated in peripheral retina. Laser done
around pre-existing retinal break. 25% SF6
injected.
Case 3 22 1 Intravitreal FB 1.4 mm FB. Site of ocular penetration 1 None
was sutured before making scleral ports.
Case 4 29 1 0.9 mm FB incarcerated in peripheral macula, with 1 None
focal sub/intra retinal bleed. Laser done around
pre-existing retinal break. SF6 injected.
Case 5 32 0.17 Previously repaired scleral wound. 1 mm nasal 0.67 2 peripheral retinal
intra-retinal FB. Partial encapsulation noted with
focal retinal pigmentation. Macular ERM peeled. breaks occurred
SF6 injected.
during PVD
induction and were
lasered.
*Visual acuity is best spectacle corrected and in decimal units rounded off to second decimal, # final acuity was measured at six months
of follow up. FB: Foreign body, PVD: Posterior vitreous detachment.
and cycloplegic for 4-6 weeks. were followed at one week, one month, technique and the lens remained clear till
Outcomes and follow up: The patients 3 months and 6 months with respect the last follow up at six months in all the
Kumar V. et al. Double Handshake Technique... www. dos-times.org 47
Techniques
cases. The mean IOFB size determined Our technique, by adding another foreign bodies. Current opinion in
after removal was found to be 1.04 mm. ‘handshake’ allows utilization of both ophthalmology. 2008;19:225-33.
No case required injection of silicone intraocular magnet (to pick the IOFB off 2. Tsang, C.W., Cheung, B.T., Lam,
oil or any other long retaining vitreous retinal surface) and forceps (to retrieve R.F. et al. Primary 23-gauge trans-
substitute. the IOFB) and adds to the safety of conjunctival suture less vitrectomy for
IOFB removal. The technique does not rhegmatogenous retinal detachment.
Discussion: 25-gauge vitrectomy have a long learning curve and is not Retina. 2008; 28: 1075–1081
systems have been used for removal assistant dependent. As seen in our 3. Rizzo S, Barca F, Caporossi T, Mariotti
of both magnetic and non magnetic results, the technique can be safely used C. Twenty-seven-gauge vitrectomy for
IOFBs4,5,6. Two critical steps in the for patients with good preoperative various vitreoretinal diseases. Retina.
removal of IOFB, which can lead to visual acuity, intact attached retina and 2015;35:1273-1278.
retinal damage, include picking it from crystalline lens. The primary advantage 4. Riemann CD, Mehta MC, Yeh EC.
the retinal surface and then taking it out of our technique is obviating the need Innovative use of a magnetized pick
of the eye through the anterior route or of 2 large sclerotomies, thus preserving for removal of an intraocular foreign
sclerotomy. Intra-ocular magnets allow the minimum invasiveness of 25-gauge body with 25-gauge transconjunctival
easy IOFB levitation from the surface of vitrectomy. Another distinct advantage sutureless vitrectomy. Retin Cases Brief
retina without damaging it. This becomes is the ability to easily manage the IOFB Rep. 2011;5:330–2.
important especially in the presence of capsule, as done in case 5. Using the 5. Sborgia G, Recchimurzo N, Niro
attached retina and good preoperative double handshake technique, the IOFB A, Sborgia L, Sborgia A, Alessio G.
visual acuity, as most of the IOFBs in can be easily debulked of such tissue. 25-Gauge Vitrectomy in Open Eye
the vitreous shift to the macula once While the non-dominant hand held the Injury with Retained Foreign Body.
vitreous removal is complete. 25-gauge IOFB using forceps, the vitrectomy cutter Journal of Ophthalmology. 2017 Jan
intra-ocular magnets are however not in dominant hand was used to remove 9;2017.
commercially available and scleral port tissue covering the IOFB. 6. Singh R, Kumar A, Gupta V, Dogra MR.
needs to be enlarged to introduce larger 25-Gauge active aspiration silicon tip-
gauge intraocular magnet. We believe that the handshake may assisted removal of glass and other
be performed in the posterior cavity as intraocular foreign bodies. Can J
The retrieval of IOFB becomes easier well, but that would require forming Ophthalmol. 2016;51:97-101.
when limbal route removal is possible another scleral port for endoilluminator. 7. Kunikata H, Uematsu M, Nakazawa T,
(where simultaneous lens management Important limitations of this technique Fuse N. Successful removal of large
is planned)4,7. however it is tedious when however include non-metallic IOFBs, intraocular foreign body by 25-gauge
crystalline lens is intact or intraocular where magnets cannot be used and large microincision vitrectomy surgery.
lens is in place. It is important to salvage IOFBs where removal through anterior Journal of ophthalmology. 2011 May
the lens since most patients with IOFBs route is recommended. 12;2011.
are young. A single port extraction of 8. Takkar B, Azad SV. (2016). Retained
IOFB using external magnets carries a To conclude, the double handshake intraocular foreign body. In: Azad
high risk of lens damage as the procedure technique allows for a very controlled and & Takkar, ed. Basics of vitrectomy.
can be rather uncontrolled8. Also a safe removal of the IOFB using 25-gauge Thieme; Chapter 10.pp. 131-144.
skilled assistant is required for holding pars plana without the need of enlarging
the external magnet. Alignment of the both the scleral ports. This technique is Correspondence to:
IOFB with the sclerotomy site along its especially useful in the presence of intact Dr. Vinod Kumar
longitudinal axis is crucial to prevent crystalline lens and retina and allows Dr. Rajendra Prasad Centre for
damage to both lens as well as retina at minimally invasive surgery in patients Ophthalmic Sciences, All India Institute
the ora serrata and is best achieved by with good pre-operative visual acuity. of Medical Sciences, New Delhi, India
re-grasping it with a forceps after it has
been levitated in to the vitreous cavity. References
Therefore both sclerotomies need to be
enlarged: one for the intraocular magnet 1. Yeh S, Colyer MH, Weichel ED. Current
and other for retrieval of IOFB. trends in the management of intraocular
48 DOS Times - May-June 2019 Kumar V. et al. Double Handshake Technique...
Photo Essay
Focal Chorioretinal Atrophy in Sympathetic
Ophthalmia
Dr. Vinod Kumar MS DNB MNAMS FRCS (Glasg), Dr. Shreyans Jain MD
Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
A16 year old male sustained penetrating injury Figure 1: Ultra wide field pseudo-colour photographs of right (a) and
to his right eye four years ago. The patient left (b) eye of a patient with sympathetic ophthalmia. Typical sunset
developed sympathetic ophthalmia six glow is visible in both eyes along with multiple small patches of focal
months after the injury and received long term chorioretinal atrophy especially in inferior fundus. SD-OCT through
steroid therapy. He subsequently developed these areas of chorioretinal atrophy in the infero-temporal fundus (c) of
inflammatory choroidal neovascularisation the right eye shows localised RPE loss with backscattering (d).
in his left eye and was treated with intravitreal Bevacizumab.
The best corrected visual acuity was 20/60 and 20/200 in
right and left eye respectively. Dilated examination revealed the
typical sun-set glow fundus bilaterally (Figure 1a & b). The left
eye showed a disciform scar at macula. In addition both eyes
showed multiple small discrete areas of focal chorioretinal
atrophy which were more numerous in the inferior fundus.
These areas of focal chorioretinal atrophy represent resolved
Dalen Fuch’s nodules which have lead to disruption of ellipsoid
layer and retinal pigment epithelium1 (Figure 1c & d).
References
1. Muakkassa NW, Witkin AJ. Spectral-domain optical coherence
tomography of sympathetic ophthalmia with Dalen-Fuchs
nodules. Ophthalmic Surg Lasers Imaging Retina. 2014;45:610-
2.
Correspondence to:
Dr. Vinod Kumar
Dr. Rajendra Prasad Centre for
Ophthalmic Sciences, All India Institute
of Medical Sciences, New Delhi, India
50 DOS Times - May-June 2019 Kumar V. et al. Focal chorioretinal Atrophy in Sympathetic Ophthalmia
Photo Essay
Coat’s-Type Retinitis Pigmentosa
Dr. Pragya Saini, Dr. Prashant Jain, Dr. Neha Goel
ICARE Eye Hospital and Postgraduate Institute, NOIDA, India
Coats’ disease was first described by a Scottish arcade. A diagnosis of Coats’ disease like picture superimposed
ophthalmologist George Coats, in 1908, on RP was made. Retinal cryopexy was performed which led to
characterized by retinal vascular abnormalities, gradual improvement in vision in the right eye to 20/60 with
exudates, and haemorrhage1. In 1956, an Italian resolution of the exudation (Figure 1C and D).
ophthalmologist Zamorani described a rare
association of Coats’ disease with retinitis Discussion
pigmentosa (RP), attributing both diseases to endocrine Coats’-like RP is an atypical presentation seen in 1%–4%
hypophyseal dysfunction2. The term Coats’-type RP denotes of RP cases, usually in the later stages of the disease3. It is
that the disease is a separate entity rather than a subcategory characterized by aneurysmal dilations and telangiectatic retinal
of RP2. veins, extravascular lipid depositions, and retinal detachment
Case report (RD). It can be differentiated from typical Coats’ disease with
respect to age of presentation (older age), gender (slight female
A 40 year male who was a diagnosed case of RP presented preponderance), involvement of eye (generally bilateral),
with gradually progressive diminution of vision in his right progression (more progression), retinal location (inferior
eye since 4 months. The best corrected visual acuity (BCVA) quadrants) and can show diffuse pigmented alterations in both
was 20/200 in the right eye and 20/30 in the left eye. Slit fundi4. Classic Coats’ disease is a unilateral disorder occurring
in males in the first or second decade and has a prediliction for
lamp examination of both eyes was unremarkable. Fundus
examination revealed bilateral, mid-peripheral typical “bony the superotemporal retina5.
spicule” pigmentary changes and generalized arteriolar The Coats’ response maybe a vasodilatory response to toxic
attenuation (Figure 1A and 1B). The right eye fundus showed, in products of photoreceptor/RPE degeneration or may result
addition, presence of vascular telangiectasia and lipid exudation from chronic microvascular leakage followed by exudative RD
extending from 4 to 7 clock hours, inferior to the inferior with subsequent retinal hypoxia owing to seperation from the
choroid. It has been suggested that genetic
factors may be involved in RP with Coats’-
type exudative vasculopathy6.
Mild Coats’-type RP can be followed
up closely for signs of progression. For
patients developing exudation, retinal
or subretinal fluid, management options
include cryotherapy, scleral buckling
with subretinal fluid drainage and laser
photocoagulation of the telangiectatic
lesions to induce regression7. Cryotherapy
is preferred in peripheral retinal
telangiectasia with significant exudative
RD5. Anti- VEGF agents have also been
found to have an adjuvant role in reducing
subretinal fluid and exudation8. However,
their use may lead to vitreoretinal fibrosis
and detachment9.
An awareness of this potentially
treatable complication of RP can help with
the earlier diagnosis, timely treatment and
a better prognosis. Therefore, detailed
peripheral fundus examination should
Figure 1: (a) Colour fundus photograph of the right eye at presentation showing mild disc pallor, always be performed in RP patients in
arteriolar attenuation and a dull foveal reflex. (b) Typical “bony spicule” pigmentation seen order to avoid missing out any exudative
superiorly in the mid-peripheral retina (c) Intraretinal lipid exudation alongwith telangiectatic and telangiectatic lesions in the periphery.
vessels present inferior to the disc and inferior arcade, suggesting Coats’-type retinitis pigmentosa
(d) Resolution of the exudation and telangiectatic vessels with fibrotic scar formation following
cryotherapy.
52 DOS Times - May-June 2019 Saini P. et al. Coats’-Type Retinitis Pigmentosa
References Ophthalmol 2014;59:30-46. Photo Essay
6. Pruett RC. Retinitis pigmentosa: clinical
1. Nika B, Shreya B, Ninel ZG, Sharon Correspondence to:
F, Ingrid US. Characteristics and observations and correlations. Trans Dr. Pragya Saini
Management of Coats Disease. Eyenet Am Ophthalmol Soc 1983;81:693–735. ICARE Eye Hospital and Postgraduate
Magazine 2017 Apr; 43-44. 7. Hartong DT, Berson EL, Dryja Institute, NOIDA, India
TP. Retinitis pigmentosa. Lancet
2. Zamorani G. Una rara associazone 2006;368:1795–809.
di retinite di Coat’s con retinite 8. Villegas VM, Gold AS, Berrocal AM,
pigmentosa. Gior Ital Oftalmol Murray TG. Advanced Coats’ disease
1956;9:429–443. treated with intravitreal bevacizumab
combined with laser vascular ablation.
3. Kajiwara Y. Ocular complications of Clinical Ophthalmology 2014;8:973–
retinitis pigmentosa. Association with 976.
Coats’ syndrome. Jpn J Clin Ophthalmol 9. Ramasubramanian A, Shields CL.
1980;34:947-955. Bevacizumab for Coats’ disease with
exudative retinal detachment and
4. Khan JA, Ide CH, Strickland MP. risk of vitreoretinal traction. Br J
Coats’-type retinitis pigmentosa. Surv Ophthalmol 2012;96:356–359.
Ophthalmol 1988;32:317-332.
5. Sigler EJ, Randolph JC, Calzada
JI, Wilson MW, Haik BG. Current
management of Coats disease. Surv
Saini P. et al. Coats’-Type Retinitis Pigmentosa www. dos-times.org 53
Photo Essay
Spectral Domain Optical Coherence Tomography
in Congenital Retinal Macrovessel
Dr. Neha Goel MS, DNB, MNAMS, FRCS (Glasg), Dr. Gaurav Shukla MBBS, Pragya Saini MBBS, DO
ICARE Eye Hospital and Postgraduate Institute, NOIDA, India
Congenital retinal macrovessel (CRM) is Figure 1b: Fundus of the left eye showing dilated, tortuous infero-
characterised by the presence of an abnormal vein temporal vein. Its tributaries can be seen to cross the horizontal raphe
crossing the horizontal raphe and the macula. It and one of them is encircling the fovea.
is usually asymptomatic and rarely causes visual
disturbance. We describe the spectral-domain
Optical Coherence Tomography (SD-OCT) findings
including the ganglion cell layer and the retinal nerve fibre layer
thickness in a ten year old girl with unilateral congenital retinal
macrovessel picked up on routine examination.
Case report
A ten year old girl was referred based on ‘something
abnormal’ found on fundus examination of the left eye during a
routine eye check-up. Her visual acuity was 20/20 OU. Fundus
examination in the right eye was normal (Figure 1a). Fundus
examination in the left eye showed a dilated, tortuous infero-
temporal vein. On reaching the infero-temporal aspect of
the macula, two of its tributaries marched upwards crossing
the horizontal raphe. The nasal one of these ran horizontally
towards the fovea, splitting into two on its temporal aspect and
then encircling the fovea (Figure 1b). Fluorescein angiography
revealed, in addition, altered perifoveal capillary network and
foveal avascular zone. Though anastomoses were seen between
its branches and that of the supero-temporal vein, there were
no abnormal leakages or capillary nonperfusion areas (Figure
Figure 1a: Normal fundus in the right eye. Figure 1c: Fluorescein angiography of the left eye showing altered
54 DOS Times - May-June 2019 perifoveal capillary network and anastomoses between branches of the
infero-temporal and the supero-temporal vein.
1c). On spectral-domain Optical Coherence Tomography (SD-
OCT) with RTVue SD-OCT (Optovue Inc, Fremont, California,
USA), the vessel showed increased reflectivity in the inner
retinal layers with underlying shadowing. No defects of the
Goel N. et al. Spectral Domain Optical Coherence Tomography...
Photo Essay
Figure 2a: Horizontal SD-OCT scan through the fovea showing Figure 2b: Vertical SD-OCT scan through the fovea.
increased reflectivity in the inner retinal layers corresponding to
the aberrant vessel with underlying shadowing.
Figure 2c: Comparable macular thickness between the two eyes in all Figure 3a: Ganglion cell layer thickness in the two eyes, showing no
nine quadrants. significant difference.
Figure 3b: Peripapillary RNFL measurements in the right eye. Figure 3c: Peripapillary RNFL measurements in the left eye. No
significant differences despite presence of the aberrant vessel in this
eye.
photoreceptor layer were detected in Comment on routine examination as they are not
the visible area (Figure 2a,b). Macular associated with visual disturbances.
thickness maps of the two eyes were Congenital retinal macrovessel Reduction of vision, if present, has been
comparable, including foveal thickness (CRM), first described by Mauthner in attributed to haemorrhage, foveal cyst,
(Figure 2c). Also, the ganglion cell layer 1869, is a large vessel, usually a vein, or to the mere presence of the aberrant
(GCL) and the retinal nerve fibre layer which traverses through the central vessel in the fovea1-3. It seems that the
(RNFL) thickness were comparable in macula and has large tributaries development of the retinal neural and
both eyes (Figure 3a,b,c). In view of extending on both sides of the horizontal vascular components is independent of
no ocular complaints, the patient was raphe1. The presence of CRM is of rare each other4,5 thereby not affecting visual
advised annual routine checkups. occurrence. They are generally found
Goel N. et al. Spectral Domain Optical Coherence Tomography... www. dos-times.org 55
Photo Essay
acuity in cases with CRM. To summarize, SD-OCT shows 5. Volk D. Visual function studies in a case
SD-OCT has been a very useful relatively normal foveal anatomy, GCL of large aberrant vessels in the macula.
and RNFL thickness in a case with CRM, Arch Ophthalmol 1956; 55: 119–122.
addition to the armamentarium of an corroborating with the minimal visual
ophthalmologist. In the present case, disturbances in majority of these cases. 6. Han JR, Jeon GS, Park JH, Seong HK,
it confirmed the findings of hyper- Nam WH, Kim HK. Congenital retinal
reflectivity of inner retinal layers and References macrovessel and foveal dysplasia
underlying shadowing as described on of retinopathy of prematurity. Jpn J
time-domain OCT.6 However no macular 1. Brown GC, Donoso LA, Margargal LE, Ophthalmol 2009;53:277-279.
edema was appreciated. In addition, the Goldberg RE, Sarin LK. Congenital
photoreceptor layer was normal with no retinal macrovessels. Arch Ophthalmol Correspondence to:
localised defects. The thickness of the GCL 1982; 100: 1430 –1436. Dr. Neha Goel
and the RNFL was comparable in the two ICARE Eye Hospital and Postgraduate
eyes justifying equal visual acuity despite 2. de Crecchio G, Mastursi B, Alfieri Institute, NOIDA, India
the presence of the aberrant vessel. MC, Pignalosa B. Congenital retinal
macrovessel. Ophthalmologica 1986;
In cases where CRM passes directly 193: 143–145.
over foveola, the shadowing effect
would be present on the underlying 3. de Crecchio G, Pacente L, Alfieri MC,
photoreceptors for all visual stimuli, as is Greco GM. Valsalva retinopathy
present for the laser beams of OCT. This associated with a congenital retinal
would explain the cause of decreased macrovessel. Arch Ophthalmol 2000;
vision in such patients. 118: 146–147.
4. Ashton N. Retinal angiogenesis in the
human embryo. Br Med Bull 1970; 26:
103–106.
56 DOS Times - May-June 2019 Goel N. et al. Spectral Domain Optical Coherence Tomography...
Case Reports
Bilateral Optic Disc Edema in Retinitis Pigmentosa
with Bardet-Biedl Syndrome
Dr. Vinod Kumar MS DNB FRCS (Glasg), Dr. Abhidnya Surve, Dr. Kusumitha B.
Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
Abstract: Retinitis pigmentosa is a commonly encountered entity in clinical practice. The presence of buried disc drusen may give false
appearance of disc edema. True disc edema however is a very rare feature of retinitis pigmentosa. This article describes a case of bilateral
disc edema in case of retinitis pigmentosa with Bardet-Biedl syndrome. The diagnosis was challenging due to the presence of optic disc
drusen in one eye. The work up and potential etiology of disc edema in such a case is discussed.
Key Words: Disc edema, Optic disc drusen, retinitis pigmentosa, Bardet-Biedl syndrome.
Retinitis pigmentosa (RP) is associated with optic degeneration. No treatment was advised, as there were no signs
disc drusen in 10% of cases1. The presence of of active inflammation. The patient was explained about the
buried disc drusen may give false appearance of nature of the condition and was advised regular follow up. The
disc edema. True disc edema however is a very clinical picture remained unchanged at one-month follow up.
rarely described entity in retinitis pigmentosa.
We describe a case of bilateral disc edema in a Discussion
patient with Bardet-Biedl syndrome and retinitis pigmentosa.
Retinitis pigmentosa is a group of inherited, progressive
Case report disorders of retinal photoreceptors and pigment epithelium
(RPE) characterized by nyctalopia and progressive constriction
A 20-year-old obese, short statured male presented with of visual fields. Fundus findings in RP consist of typical triad
history of night blindness since childhood. The patient had of arterial attenuation, bony spicules and waxy disc pallor.
hexadactyly with extra digit in each hand. The patient also Other ocular associations of RP include posterior sub-capsular
had speech abnormalities. There was no history of similar cataract, cystoid macular edema and macular atrophy2.
complaints in other family members or history of consanguinity Optic disc drusen especially when buried can mimic disc
in parents. There was no history of headache, vomiting or any edema. Persistent optic disc edema can worsen the already
neurological problems. compromised visual fields in RP and add to the visual disability
of patient.
The best-corrected visual acuity was 20/20 OU with
-2D sphere. Anterior segment including intraocular pressure There is only one case report of bilateral disc edema in
was unremarkable OU. Pupillary reactions, direct as well RP with Bardet-Biedl syndrome by Sachdev et al3 where the
as consensual were normal. There were no cells in anterior patient presented with sudden loss of vision in both the eyes
chamber or vitreous cavity. Fundus OU (Figure 1a &1b) showed and it improved over a period of time with systemic steroids.
optic disc edema, arterial attenuation, mid-peripheral retinal However the patient did not have any decreased vision in this
pigmentary changes and scattered bony spicules. Spectral case. Bilateral disc edema in RP has also been described in
domain optical coherence tomography showed no cystoid Usher syndrome type 2 by Villa et al4 and simple RP in Ozdek
macular edema (CME). Fluorescein angiogram (Figure 1c & et al5.Unilateral disc edema has been described in juvenile RP
1d) revealed leakage from optic nerve head confirming the by Hayasaka et al6.
presence of disc edema. A careful examination of the optic disc
revealed optic disc drusen only in OD (Figure 2a), which was The most accepted hypothesis of disc edema in RP is
confirmed with the ultrasound B-scan (Figure 2b). Visual fields inflammation secondary to rapid photoreceptor and RPE
OU demonstrated ring scotoma. Electro-retinogram revealed degeneration. The inflammation leads to vascular leakage at
extinguished responses OU. A diagnosis of Bardet-Biedl the optic disc, which may cause optic disc edema. In the series
syndrome with retinitis pigmentosa was made. reported by Spalton et al, 8 out of 25 patients had leakage at
disc with swollen disc in three patients7.
Complete blood count and routine examination of urine was
normal. Patient’s fasting sugar was 102mg/ml. Blood pressure Other possible causes may include ischemic optic
was 110/72 mm Hg. Serology for syphilis was negative. X-ray neuropathy, optic neuritis, raised intracranial pressure and
chest was normal. Ultrasound of abdomen revealed no renal or inflammatory diseases of retina and optic nerve, which were
hepatic abnormality. Computerized tomography of head and ruled out by a thorough examination and relevant investigations
orbit showed no space occupying lesion or signs of raised intra- in our case.
cranial pressure (ICP). The optic disc edema was presumed to
be because of inflammation resulting from rapid photoreceptor To conclude, bilateral optic disc edema is a rare occurrence
in retinitis pigmentosa and may be because of inflammation
due to photoreceptor/RPE degeneration. Before proceeding
Kumar V. at al. Bilateral Optic Disc Edema in Retinitis Pigmentosa... www. dos-times.org 57
Case Reports with extensive ocular and systemic
investigations to find the cause of disc
Figure 1 edema one must consider the common
Figure 2 occurrence of optic disc drusen, which
can mimic disc edema.
References
1. Grover S, Fishman GA, Brown Jr J.
Frequency of optic disc or parapapillary
nerve fiber layer drusen in retinitis
pigmentosa. Ophthalmology.1997;
104:295–8.
2. Hamel C. Retinitis pigmentosa.
Orphanet J Rare Dis. 2006; 1:40.
3. Sachdev MS, Verma L, Garg SP, Moonis
M, Shekar CH, Gupta NK. Bilateral disc
oedema in retinitis pigmentosa--an
unusual sign. Jpn J Ophthalmol. 1987;
31:621-6.
4. Villa AM, Anderson SF, Abundo RE.
Bilateral disc edema in retinitis
pigmentosa. Optom Vis Sci. 1997;
74:132-7.
5. Ozdek S, Ozdogan S, Sezgin T, Gurelik
G. Bilateral disc edema and unilateral
macular hole in a patient with retinitis
pigmentosa. Eur J Ophthalmol. 2006;
16:487-90.
6. Hayasaka S, Noda S, Setogawa T. Disc
edema in juvenile retinitis pigmentosa.
Ann Ophthalmol. 1991; 23:304-7.
7. Spalton DJ, Bird AC, Cleary PE. Retinitis
pigmentosa and retinal oedema. Br J
Ophthalmol. 1978; 62:174-82.
Correspondence to:
Dr. Vinod Kumar
Dr. Rajendra Prasad Centre for
Ophthalmic Sciences, All India Institute
of Medical Sciences, New Delhi, India
58 DOS Times - May-June 2019 Kumar V. at al. Bilateral Optic Disc Edema in Retinitis Pigmentosa...
Case Reports
A Case of Identity – Tamoxifen Toxicity
Dr. Awaneesh Upadhyay Dnb, Dr. Isha Agarwalla Dnb, Dr. Divakant Misra Do, Dnb,
Dr. Chintan Desai Do, Dnb, Dr. Fazil Khurram Do, Dnb, Dr. Manabjyoti Barman Do, Dnb
Sri Sankaradeva Nethralaya, Guwahati, Assam, India
Abstract: A 45 years old female patient duration post breast cancer chemotherapy and radiotherapy presented with bilateral reduced
visual acuity to 6/18, N8 in both eyes (OU). Anterior and posterior segments were unremarkable on examination, SDOCT showed presence
of pseudo-cavitations in the subfoveal region without presence of any crystalline deposits or macular edema in both eyes (OU) with
disruption of inner photo receptor segments in the left eye (OS).Electrophysiological testing were done as adjuvants.
Tamoxifen is a nonsteroidal antiestrogen, Figure 1: SD OCT OD- Pseudo-cystic spaces were noted in the sub-
belonging to the family of selective estrogen foveal region with intact ILM and thinning of the foveal layers and no
receptor (ER) modulators, these drugs have major changes were detected in the outer layers. Hyper – reflective dot
the ability to occupy ERs, in breast tissue they echo noted in the inner plexiform layer (yellow arrow).
act as ER antagonists. Resulting in tamoxifen
to be used as adjuvant in endocrine therapy Figure 2: SD OCT OS-Few Pseudo-cystic spaces seen sub-fovealy with
for women with hormone-responsive breast cancer1. Ocular intact ILM with disruption of inner photoreceptor segments.
toxicity of tamoxifen are rare with incidences ranging between
0.9% and 12.0%, seen significantly higher with higher doses2. Discussions
Ocular manifestations of tamoxifen toxicity include vortex Earlier crystalline retinopathy was the hallmark of
keratopathy, lens deposits, optic neurits, and maculopathy
which includes crystalline retinopathy with or without macular tamoxifen toxicity. High dosage of more than 120 mg daily with
edema, and pseudocysticfoveal cavitation2-4. We report, herein, clinical findings let to the above observation5.
a case of a 45-year-old woman presenting with bilateral,
painless progressive visual deterioration after treatment with With the standard dose of tamoxifen reduced to 20 mg
tamoxifen and describe the SD OCT findings. daily, there have been fewer presentations with significant
ocular toxicity clinically. With the advent of newer imaging
Case modalities very subtle and early changes of maculopathy can
be picked up even with low dose of tamoxifen as demonstrated
A 45 year old female patient on 20 mg twice daily dose in our patient and also in recent studies2-4,6,8.
of tamoxifen for 2 year (cumulative dose, 14.6 g) following
right mastectomy performed 4 years ago for breast cancer, It has been suggested tamoxifen inhibits muller cell
presented to the OPD with painless, progressive vision loss in glutamate aspartate transporters which are required for
both eyes (OU) of 4 months duration. On examination her best glutamate uptake and recycling in the retina. Müller cell
corrected visual acuity (BCVA) was 6/18; N8. Anterior segment dysfunction and neuronal apoptosis is observed from
examination with slit lamp biomicroscopy was unremarkable, excessive glutamate7 seen as pseudocavities on SDOCT. The
fundus appeared grossly normal with blunted foveal reflex;
there were no ectatic capillaries, blunted venules, retinal
pigment plaques, pigmentations or foveal atrophy. Colour
vision was normal in both eyes. Enhanced depth imaging (EDI)
SD OCT showed right eye (OD) pseudo-cystic spaces in the sub-
foveal region with intact internal limiting membrane (ILM),
thinning of the foveal layers, a hyper – reflective dot noted in
the inner retinal layers (yellow arrow), no major changes were
detected in the outer layers (Figure 1), OS showed pseudo-
cystic spaces sub-fovealy with intact ILM with disruption
of inner photoreceptor segments, intact retinal pigment
epithelium (Figure 2). Fundus autofluorescence (AF) showed
absence of the normal foveal hypoautofluorescence (Figure 3).
Fluorescein angiography shows late staining in both eyes with
no leaks (figure 4). Multifocal electro-retinogram (mERG) was
within normal limits in OU. Electro-oculogram was performed
twice but the results were equivocal (Figure 5).
Upadhyay A. et al. A Case of Identity – Tamoxifen Toxicity www. dos-times.org 59
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