dos_sep_2013

Evolution

a very important new parameter; namely, duty cycle. The provide a wider cone angle of illumination despite smaller
duty cycle of a vitrectomy probe indicates the percentage light fibers. Chandeliers driven by the Xenon light sources
of time the port is open measured against the total time provide a spectacular panoramic viewing environment
of the cut cycle. High flow rates can be achieved with a within which “true” bimanual surgery can be performed
“biased open” duty cycle, in which the port remains open safely. Future research hinges on finding ways to maximize
during most of the cycle, producing greater flow of vitreous illumination levels while at the same time reducing the risk
into the vitrector. Alternatively, the surgeon can achieve of phototoxicity.
port-based flow limiting with a “biased closed” duty cycle. The saga of vitreoretinal surgery reflects man’s ingenuity
In this case, the port remains closed for a longer duration, and how the advances in technology have built upon
with consequently lower flow. them an edifice of algorithms which can be used by all
Improvement in illumination- The development of ophthalmologists to treat conditions, hence to untreatable,
powerful, safe Xenon light sources as compared to the with high success rate. With each passing day, the progress
older halogen systems has come at an opportune time for is being made and the present generation of retinal surgeons
retinal surgeons to take advantage of 23 & 25G surgical is the witness to these remarkable moments.
techniques. The newer endoilluminaters are more rigid and

Delhi
Ophthalmological
Society

Monthly Clinical Meeting, October 2013

Venue: Seminar Hall, 3rd Floor Trauma Block, DDU Hospital, Hari Nagar, New Delhi -110064
Date: 27th October, 2013 (Sunday)

Tea with Snacks & Registration: 10:00 a.m. Onwards 50 Early Bird Prizes

Clinical Session: 11:00 a.m. onwards

Clinical Cases: : Dr. Rima Jain 10 mins
1. mins Choroidal Granuloma-Atypcal presentation of : Dr. Amit Mehtami
Ocular Tuberculosis
Discussant

2. Desferrioxamine induced bilateral CSR-in a case of Thalassaemia : Dr Ankur Singh 10 mins
Discussant : Dr. Amit Mehtami

Clinical Talk: : Dr. M.C. Agarwal 15 mins
• Update on Management of Diabetic Retinopathy

Mini Symposium: Technological Innovations in Newer IOLS - Controversies & Limitations
Chairman: Dr. S. Bharti, Co-Chairman: Dr. J.S. Titiyal, Convenor: Dr. M.C. Agarwal

1. Aspheric IOLs- Facts & Myths : Dr. J.S. Bhalla 12 Mins
2. Accomodative IOLs - Has their time come : Dr. H.C. Gandhi 12 Mins
3. Toric IOLs -Conceptual analysis of residual astigmatism : Dr. N.Z. Farooqui 12 Mins
after Toric IOL Implantation

4. ICL : Dr. Rajesh Hans 12 Mins

Lunch

Programme Sponsored by - M/s. Shelon Pharmalab

64 l DOS Times - Vol. 19, No. 3 September, 2013

Cotton Wool Spots PG Corner

Vinod K. Aggarwal
MS, DNB, MNAMS

Vinod K. Aggarwal MS, DNB, FRCS (Glag), Bhuvan Chanana MD, DNB, FICO
University College of Medical Sciences & G.T.B. Hospital, Delhi

Cotton wool spots (Soft exudates) are small, fluffy cotton wool spots is aimed primarily at finding the
white opacities (Figure 1) in the nerve fibre layer of underlying cause. The common disorders like Diabetes and
retina. These usually result from infarction of small retinal Hypertension should always be asked prior to examination.
arterioles in nerve fibre layer. The reduced perfusion in the Symptoms: Mostly these are asymptomatic but sometimes,
inner retina causes ischemia of the nerve fiber layer which patients can have complaints of small scotoma of acute
in turn disrupts axoplasmic flow. This build up of axoplasm onset.
is visible ophthalmoscopically as a ‘‘cotton wool spot” Signs: Typically fluffy white opacities are seen in superficial
Etiology: In most of the cases, cotton wool spots are an retina which may or may not obscure underlying blood
indicator of underlying systemic vascular diseases, the vessels (Figure 2). The spots usually resolve in weeks to few
most common being Diabetic Mellitus. Cotton wool spots months, leaving a small depression known as “Depression
can be associated with a large number of disorders. Table1 Sign”.
summarises the important causes of cotton wool spots. On fluorescein angiography (FFA), cotton wool spots are
History and Examination: The history in patients with
Figure 1: Multiple cotton wool spots in the left eye
Table1: Common causes of Cotton wool spots of a patient with Hypertensive retinopathy

Vascular Diseases Diabetic retinoapathy,
Hypertension retinopathy,
Arterial and venous occlusions,
Ocular ischemic syndrome,
Papilloedema

Hematologic diseases Anaemia, Leukemia, Sickle cell
anaemia, Thrombocytopenia

Trauma Purtscher retinopathy, Radiation
retinopathy

Infectious diseases HIV retinopathy (cotton wool
spots are most common eye
manifestation of AIDS and
result from microvasculopathy),
Neuro-retinitis, Subacute
bacterial endocarditis

Collagen vascular SLE, Giant cell arteritis, Behcet’s
diseases disease

www. dosonline.org l 65

PG Corner

Figure 2: Cotton wool spots along with other Figure 3: FFA of the patient with NPDR shows
diabetic changes in a case of Non-proliferative hypo fluorescent areas corresponding to cotton
wool spots with micro-aneurysms at the edges.
diabetic retinopathy (NPDR).

seen as hypo fluorescent spots. The hypo fluorescence However they may persist for long in certain patient with
is because of blockage by the axoplasm stasis as well as diabetes. Treatment is aimed at the underlying cause.
capillary non-perfusion. This may be associated with
surrounding aneurysms and altered capillary bed (Figure 3). For Sale
On Optical Coherence Tomography (OCT) cotton wool
spots are seen as hyper-reflective lesion in the inner retinal SHIV NIPPON
layers. microscope in good
Best corrected visual acuity: Is documented for records. working condition
Anterior segment examination: Detailed anterior segment Sparingly used
examination with special emphasis on Intraocular pressure, APPA Phaco Handpiece
pupillary reactions and rubeosis iridis is done.
Dilated fundus examination: A dilated fundus examination
is then done with slit lamp biomicroscopy. The cotton wool
spots are predominantly seen in peri-papillary region or at
posterior pole. The associated findings like microaneurysms,
retinal hemorrhages (dot-blot or flame shaped), preretinal
hemorrhages, hard exudates, disc or macular edema should
be noted.
FFA/OCT: This in association with good history provides us
the diagnosis in majority of the patients.
Treatment: Cotton wool spots do not require any treatment
on their own. They tend to disappear in weeks to months.

Contact: 9811011443

66 l DOS Times - Vol. 19, No. 3 September, 2013

MonthlyMoMnthelyetMineegtinCg oCronrneer

Secretory PituitaryTumour Presenting
as Ocular Hypertension
Shikha Gupta
MD

Shikha Gupta MD, Ramanjit Sihota MD, Viney Gupta MD,
Tanuj Dada MD, Varun Gogia MD, Ajay Sharma B.Sc

Dr. Rajendra Prasad Centre for Ophthalmic Sciences,
All India Institute of Medical Sciences

A30 year old female presented with complaints of glaucoma differ from patients with glaucoma caused
ocular discomfort for 8 months and increase in body secondary to exogenously administered corticosteroids,
weight, polyuria and fatigue for two years. There was in running a lower risk of developing glaucomatous
associated pedal edema, truncal obesity, facial melanosis damage and having an overall better ocular prognosis1.
and hirsutism. Her best corrected visual acuity (BCVA) was Endogenous steroid induced glaucoma should be suspected
20/20 both eyes. Her baseline Intra ocular pressure (IOP) in patients with systemic features of hormonal imbalance,
was 50 mmHg OD and 56 mmHg OS, and pachymetry
was normal. There was no history of use of exogenous Figure 1: Preoperative disc photographs of the first
steroids or family history of glaucoma. On examination, patient OD, OS demonstrating healthy neuroretinal rims
she had normal anterior chamber depth, open angles on (a) (b)
gonioscopy and a cup disc ratio of 0.4:1 OU. (Figure 1). Figure 2(a): Photomicrographs showing tumour cells
Humphrey Field analyzer (HFA) 30-2 was within normal arranged in sheets with eosinophilic cytoplasm and vesicular
limits. Raised blood pressure (210/120 mmHg consistently)
and persistently elevated blood sugars (between 301 and nuclei after pituitary resection (A, H&E x200).
480 mg/dl) were found. Endocrine investigations showed Figure 2(b): Tumour cells are immunopositive for ACTH
elevated plasma cortisol (35.2 ug/ ml) (range 4.3 – 22.4
ug/ ml). Overnight dexamethasone suppression test (2 hormone (B, x 200)
mg) confirmed raised serum cortisol level. MRI depicted a
small well-defined focal lesion of size 7 x 3 mm in the right
adenohypophysis.
She underwent transsphenoidal hypophysectomy.
Histopathology from excised specimen revealed
basophilic monomorphic pituitary cells immunopositive
for Adrenocortico tropic harmone (ACTH). (Figure 2 a and
b) A diagnosis of ACTH-dependent Cushing Syndrome
with endogenous steroid induced ocular hypertension
was made. Two years postoperatively, she is off glaucoma
medications, with a normal diurnal variation of intraocular
pressure and no evidence of optic neuropathy.
Question: How does endogenous steroid induced
glaucoma differ from intraocular pressure rise from
exogenous steroid administration?
Answer: Patients with endogenous steroid induced

www. dosonline.org l 69

Monthly Meeting Corner

in conditions when IOP is not controlled despite maximum Answers: Causes include an incomplete resection,
medical therapy, or persistent headache. Systemic features tumour recurrence or enhanced steroidal sensitivity in
like purple striae, facial plethora, proximal myopathy, conditions like high myopia, diabetes, Chronic open angle
hypertension, obesity, and uncontrolled diabetes along glaucoma (COAG), connective tissue diseases or familial
with ocular hypertension led to the suspicion of Cushing predisposition10. Rise in intraocular pressure along with
Syndrome2. progressive disc changes may serve as early markers of
Question: How does steroid exposure cause glaucoma? tumour recurrence.
Answer: Exposure to glucocorticoids induces metabolic References
changes in extracellular matrix, cytoskeletal re-organization,
and changes in gene expression and cell function thus 1. Guaraldi F, Salvatori R. Cushing syndrome: maybe not so uncommon
producing permanent changes in the human trabecular of an endocrine disease. J Am Board Fam Med. 2012; 25:199-208.
meshwork3,4.
Question: How do you differentiate between visual field 2. Huschle OK, Jonas JB, Koniszewski G, et al. Glaucoma in
defects caused by neurological compression by pituitary Central Hypothalamic-Hypophyseal Cushing Syndrome. Fortschr
tumor or due to glaucoma from hormonal secretion? Ophthalmol. 1990; 87: 453-6.
Answer: A compressive tumor etiology should be sought
when one finds features suggestive of optic nerve pallor in 3. Wordinger RJ, Clark AF. Effects of glucocorticoids on the trabecular
excess of cupping, absent disc haemorrhages, poor disc/ meshwork: towards a better understanding of glaucoma. Prog Retin
field correlation, vertically aligned field loss, visual acuity Eye Res. 1999;18:629-67.
<20/40, poor colour vision, and age younger than 50
years5-7. 4. Valkusz Z, Tóth M, Boda J, Nagy E, Julesz J. The importance of early
Question: What is the treatment modality for endogenous diagnosis in acromegaly. Orv Hetil. 2011; 152:696-702.
steroid induced glaucoma?
Answer: Therapy in cases with hormone secreting 5. Greenfield DS, Siatkowski RM, Glaser JS, Schatz NJ, Parrish RK
pituitary tumours requires the removal of the source of 2nd. The cupped disc. Who needs neuroimaging? Ophthalmology
these hormones, as well as IOP control8. 26.5% patients 1998;105: 1866-74.
with steroid induced glaucoma eventually require
trabeculectomy for optimum IOP control9. Our patient 6. Drummond SR, Weir C. Chiasmal compression misdiagnosed as
responded well to pituitary surgery. normal-tension glaucoma: can we avoid the pitfalls? Int Ophthalmol.
Question: What are the causes of persistent IOP rise/ 2010;30:215-9.
glaucoma relapse after tumour resection?
7. Greenfield DS. Glaucomatous versus nonglaucomatous optic disc
cupping: clinical differentiation. Semin Ophthalmol. 1999;14:95-
108

8. Lesiewska-Junk H, Malukiewicz G. Glaucoma in patient with
pituitary tumour--case report. Klin Oczna. 2009; 111:336-8.

9. Sihota R, Konkal VL, Dada T, Agarwal HC, Singh R. Prospective,
long-term evaluation of steroid-induced glaucoma. Eye (Lond).
2008; 22:26-30.

10. Stokes J, Walker BR, Campbell JC, et al. Altered peripheral
sensitivity to glucocorticoids in primary open-angle glaucoma.
Invest Ophthalmol Vis Sci. 2003; 44:5163-7.

Date: Saturday & Sunday, 30th November & 1st December, 2013
Venue: Manekshaw Centre, Dhaula Kuan, Delhi Cantt., Delhi

More details please visit us: www.dosonline.org

70 l DOS Times - Vol. 19, No. 3 September, 2013

MonthlyMoMnthelyetMineegtinCg oCronrneer

Choroidal Osteoma with Choroidal Anil B. Gangwe
Neovascular Membrane (CNVM) MD

Anil B. Gangwe MD

Dr. Rajendra Prasad Centre for Ophthalmic Sciences,
All India Institute of Medical Sciences

A38 years old female presented with gradual, painless, Bevacizumab in view of associated active CNVM. Patient
progressive decrease in vision in right eye since two was followed up after 4 weeks of injection and subjectively
months. This was associated with distortion of images. She improved vision and decreased metamorphopsia. BCVA
had no similar complains previously in either of the eye. improved to 6/18p. Sub retinal bleed resolved OCT showed
She had no known systemic illness and did not undergo decreased size of CNVM complex and associated fluid.
any form of treatment for it. Family members had no similar To summarise, choroidal osteoma is a rare tumour typically
type of complains. seen in young female. It needs to be diffentiated from some
serious entities like choroidal metastasis and amelanotic
Examination revealed best corrected visual acuity of 6/24 in melanoma. Choroidal osteoma usually does not require
right eye and 6/6 in left eye. Anterior segment examination any treatment. Long term follow up is advocated as the
was unremarkable. Fundus examination showed 7.8× lesion may develop CNVM or may undergo decalcification.
6.5 mm oval shaped, orange yellow coloured, minimally CNVM is seen in 46–56% by 20 years of follow up and
elevated choroidal lesion located at the posterior pole is leading cause of low vision. Choroidal osteoma with
(Figure 1). It had smooth but irregular margins. Area near CNVM mandates treatment that includes photocoagulation,
the edge of lesion showed areas of RPE drop outs. RPE Photodynamic therapy (PDT) and intravitreal injection of
overlying the lesion was normal. An area of greenish grey Anti- vascular endothelial growth factor (VEGF). Recent
colour with adjacent sub retinal bleed was located within reports have shown favourable response with anti- VEGF
the lesion just superior to fovea. treatment.

Ultrasound B-scan of right eye showed highly echogenic Fig.2

lesion with post acoustic shadowing. A
scan through the same region showed high
amplitude (100%) spike. Fundus fluorescein
Fig.1

angiography (FFA) showed an area with the
lesion of early hyper fluorescence which
increased in size and intensity with time. It
also showed areas of blocked fluorescence
and window defect corresponding to sub
retinal bleed and RPE dropout respectively.
Optical coherence tomograpy (OCT)
revealed a sub retinal choroidal neovascular
membrane complex with sub retinal fluid
(Figure 2).

With these clinical findings and investigations Figure 1: Fundus photograph showing 7.8× 6.5 mm oval, orange yellow elevated choroidal lesion
a diagnosis of right of choroidal osteoma Figure 2: OCT showing sub-retinal choroidal neovascular membrane with sub retinal fluid
with CNVM was made. Patient was
planned for right eye intravitreal injection of

www. dosonline.org l 71

Forthcoming Events

OCTOBER 2013 (Saturday- Tuesday) 16th – 19th November, 2013
(Wednesday) 2nd October, 2013 American Academy of Ophthalmology:
117th Annual Meeting 2013
17th Dr. R.K. Seth Memorial Symposium & Inter Institute
Ophthalmology Quiz Venue: Ernest N. Morial Convention Center in New Orleans
Venue: Silver Oak Hall, India Habitat Centre, Lodhi Road, Email: [email protected]
New Delhi Website: www.aao.org/meetings/annual_meeting/index.cfm
Contact: Dr. Wangchuk Doma
Venu Eye Institute & Research Centre, 29th – 1st December, 2013
1/31, Sheikh Sarai Phase - II, New Delhi -110017 Eye and Beyond
Email: [email protected]
Website: venueyeinstitute.org An International update on Facial aesthetics, Ocular Oncology,
Phone: 9560286667 / 9910382749 / 011-29251155, 56 Orbit, Neurophthalmology and Ophthalmic Pathology by CFS
Education
(Thursday - Sunday) 3rd – 6th October, 2013 Venue: Hyderabad
SAARC Academy of Ophthalmology Conference Contact: Dr. Shubhra Goel +919176693459
Dr. Kaustubh Mulay +919030933453
Venue: Bhurban, Pakistan Email: [email protected], [email protected]
Contact: Dr. Amer Yaqub, Secretary Organizing Committee,
Associate Professor of Ophthalmology, Army Medical College, (Saturday- Sunday) 30th Nov. – 1st Dec., 2013
Armed Forces Institute of Ophthalmology, Rawalpindi,Pakistan Delhi Ophthalmological Society Winter Conference
Email: [email protected]
Website: saarccongress2013.com Venue: New Delhi
Phone: 0321-5365434 Contact: Dr. Rajesh Sinha, Secretary, Room No. 479, 4th Floor,
Dr. Rajendra Prasad Centre for Ophthalmic Sciences,
(Friday, Saturday, Sunday) 18th – 20th October, 2013 All India Institute of Medical Sciences,
37th Annual conference of MPSOS Ansari Nagar, New Delhi – 110029 Ph.: 011-65705229,
E-mail: [email protected]
Venue: Sadguru Netra Chikitsalaya,Chitrakoot (MP) Website: www.dosonline.org
Contact: Dr. Elesh Jain Organizing Secretary
Email: [email protected] (Saturday-Sunday) 7th – 8th December, 2013
Phone: +91-9993741000 Poona Ophthalmological Society: 6th Annual Conference
& Annual conference of All India Strabismological Society
(Friday, Saturday, Sunday) 25th – 27th October, 2013
UP State Ophthalmological Society: Annual Conference Venue: Le Meridian Hotel Pune
Contact: Dr. Santosh Bhide 09822300504, Dr Mandar Paranjpe
Venue: Jhansi (Orchha), Uttar Pradesh 09823051931, Dr Nitin Prabhudesai 09822052063
Contact: Dr. D. Nath, Geeta Netra Chikitsalaya Sirsaganj, UP, Email: [email protected]
AND Dr Prakash Gupta, Dr Jiya Lal Memorial Hospital Pvt Ltd
Opp Medical College Jhansi, UP (Thursday- Sunday) 6th - 11th February, 2014
Email: [email protected] 72nd Annual Conference of All India Ophthalmological
Society (AIOC-IJO Diamond Jubilee Conference 2014)
(Monday - Thursday) 28th – 31st October, 2013
ASIA-ARVO 2013 Venue: Agra, Uttar Pradesh, India
Contact: Dr. S.K. Satsangi, Professor, Department of
Venue: The Ashok, Chanakyapuri, New Delh, India Ophthalmology, S.N. Medical College, Agra,
Contact: Conference Secretariat, Room No. 474-475 Mobile : +91-9897069441, Email: [email protected]
Dr. Rajendra Prasad Centre for Ophthalmic Sciences, AIIMS, Website: www.aioc2014.com
New Delhi-110029, India, Phone: 011-26593144-45,
Email: [email protected]
Website: www.asiaarvo2013.org

8th – 10th November, 2013
Karnataka Ophthalmic Society Annual Conference 2013

Venue: Hassan
Contact: Dr. Kavitha.C.V., Prof & HoD, Dept. of Ophthalmology,
Room No. 18, HIMS, S.C.Hospital campus,Hassan,
Karnataka.- 573201
Email: [email protected]
Phone: 0-9448064116

Delhi
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q Email : [email protected] www. dosonline.org l 75

DOS Times Quiz Delhi
Ophthalmological
Society

Instructions:

1. Please return your answers to [email protected] or mail them to “The Quizmaster, DOS Times Quiz, Dr. Rajesh Sinha,
Room No. 479, Dr. R.P. Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, Ansari Nagar, New Delhi -
110029”. Please write your DOS membership number along with your answers.

2. The answers should reach not later than 20th November, 2013.
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Quiz Prizes Sponsored by

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Food for Thought

Instructions:

It seems retina specialists are good foodies considering the multiple references to culinary items in fundus descriptions. Are you
the biggest foodie yet?

Fill in the blanks below to reveal the names of retinal diseases related to the name of the food item described.

A. Egg B. Salt and Pepper

e o o eia ue a

e io a

C. Pizza Pie u D. Tomato Catsup e ia
oeaoi ea u io

ei i i ei o

Answer for August issue of DOS Times

(a) c a v i t r o n

(b) p o l y m e t h y l m e t h a c r y l a t e
(c) l e n s t a r

(d) e m u l s i f i c a t i o n

Unscramble the highlighted alphabets to name a ring which helps manage small pupils during cataract surgery.
ma l y u g i n

# ###

Membership No. __________ Name : _______________________Mobile No. _____________Email: _______________

Answer to DOS Times Quiz September 2013 B. _________________________________________ l 77
A. __________________________________________
C. __________________________________________ www. dosonline.org
D. _________________________________________

Tearsheet

Tamponading Agents in
Vitreo-Retinal Surgery

AIM • Up rolling giant retinal tear
To keep the retina attached by creating internal tamponade • Pneumatic retinopexy
of retinal breaks, prevent fluid from entering a break, helps • Scleral buckle
retinal pigment epithelium (RPE) in faster absorption of sub Complications
retinal fluid. • Glaucoma
Materials used • Cataract
Gases • Migration of bubble into sub-retinal space
First used by Ohm. Gases have the highest surface tension • Small bubble size
and specific gravity lower than water. Buoyancy of gas • Hypotony
bubble keeps the retina against RPE. Three phases of • Iatrogenic break formation
gas dynamics are seen in the vitreous cavity- expansion, Perfluorocarbon liquids (PFCL)
equilibrium, and dissolution. After vitrectomy a non- • High specific gravity, heavier than water
expansile gas fill is done, where as in pneumatic retinopexy, • Synthetic fluorinated hydrocarbons containing carbon-
pure expansile bubble is used.
Various gases used are fluorine bonds. Viscosity ranges from 0.8 to 2.7 milli
• Air - Pascal seconds and sp gravity 1.76- 2.03
• Sulphur hexafluoride (SF6): used at isovolumetric • Optically clear, visible PFCL- fluid interface, high
boiling point- allow endophotocoagulation, immiscible
concentration, after fluid-gas exchange (20%), lasts for with water and silicone oil, easy to inject and remove.
10-14 days Indications
• Perfluoroethane (C2F6):16%, duration 30-35 days • Dissection and removal of membranes in Proliferative
• Perfluoropropane (C3F8): 12-16%, lasts for 55- 65 days vitreoretinopathy (PVR)
• Unroll folded retina in giant retinal tear (GRT)
Indications • Management of traumatic retinal detachment (RD) –
• Retinal detachment surgery with vitrectomy stabilize retina,to displace subretinal, preretinal or
• Macular hole surgery suprachoroidal blood, removal of incarcerated retina,
• Displacement of subretinal haemorrhage (choroidal and foreign body revoval

neovascularization, trauma, retinal artery macro
aneurysm)
• Superior breaks

Properties of commonly used gases

Gas Molecular wt Maximum expansion (hours) Duration Non- expansile concentration expansion
5-7 days NA 0
Air 29 NA 1-2weeks 20% 2
4-5 weeks 16% 3.3
SF6 146 24-48 6-8 weeks 14% 4
6-8 weeks 14% 4
C2F6 138 36-60

C3F8 188 72-96

C3F8 188 72-96

www. dosonline.org l 79

Tearsheet

Chemical properties of silicone oils

Agent Chemical composition Specific gravity Viscosity Surface tension
(mN/m)
Silicone oil (1000cSt) PDMS-100% 0.97 1000 21
Silicone oil (2000 cSt) PDMS- 100% 0.97 2000 21
Silicone oil (5000cSt) PDMS-100% 0.97 5000 21
Densiron 68 F6H8-30.5% PDMS 5000cSt-69.5% 1.06 1349 19.13
Oxane HD RMN3-11.9% Oxane 5700cSt-88.1% 1.02 3300 n/a
HWS 46-3000 F4H5-55% PDMS-10000cSt-45% 1.118 2903 18.8

• Removal of dislocated lens, fragments and intra ocular • GRT
lens (IOL) • Severe proliferative diabetic retinopathy ( enables rapid

• Management of suprachoroidal haemorrhage visual recovery, can examine fundus clearly during
• Complicated retinal detachment – diabetic, coloboma, postoperative follow up, reduces vascular proliferation
and post operative bleeding)
ROP • Retinal detachment associated with macular holes in
Complications pathological myopia
• Retinal toxicity • Retinal detachment associated with CMV retinitis
• Rise in IOP • Retinal detachment with coloboma and optic disc pit
• Endothelial cell loss • Trauma
Silicone oils (SO) • Endophthalmitis.
• First introduced by Paul Cibis Complications
• Made up of units of siloxane (-Si-O-) • Silicone oil in anterior chamber
• Low specific gravity and float • Glaucoma pupillary block, due to over fill of oil,
• Can be lighter or heavier than water secondary open angle glaucoma (OAG), secondary
1. Lighter than water SO –made of polydimethyl siloxane, angle closure glaucoma (ACG), oil migration into
anterior chambe (AC)
sp gravity – 0.97, float in water & aqueous. Buoyancy • Cataract
less than of gas bubble, nearly 100% fill is required to • Oil emulsification
achieve good tamponade. Interfacial tension keeps the • Band keratopathy and bullous keratopathy.
bubble single. Presence of blood, proteins and other
impurities reduces interfacial tension. When surface Raji K. MS
energy is reduced oil bubble emulsifies. Viscosity
varies from 1000cSt-5000cSt. Raji K. MS, S.K. Mishra MS
2. Heavy tamponade: Fluorinated silicone oils, heavy R&R Hospital, Delhi Cantt., Delhi
tamponades like Densiron 68, Oxane HD, HWS 46-
3000 are commercially available heavy tamponades.
Useful in retinal detachment with inferior and
posterior PVR. Iridotomy to be done superiorly. Severe
intraocular inflammation, early emulsification, sticky
SO to IOLs, retinal surface, under surface of Iris, ciliary
body are the side effects of heavy SO.
Indication of SO
• Complex retinal detachments with PVR C3 and
more (better visual recovery, reduced post operative
hypotony),

80 l DOS Times - Vol. 19, No. 3 September, 2013