Tips on Retina Practice Dr Sanjay Ahuja Dr Jatinder Bali
Tips on Retina Practice Ninth edition, 2024. Copyright © [Sanjay Ahuja and Jatinder Bali, 2024] First published 2022 by Ojasvini Bali Edited and typeset by O Bali The right of Sanjay Ahuja and Jatinder Bali to be identified as the author of this work has been asserted in accordance with the Copyright, Designs and Patents Act, 1988. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means (electronic, mechanical, photocopying, recording or otherwise), without the prior written permission of the publisher. This publication is designed to provide accurate and authoritative information. It is sold under the express understanding that any decisions or actions you take as a result of reading this book must be based on your judgement and will be at your sole risk. The author will not be held responsible for the consequences of any actions and/or decisions taken as a result of any information given or recommendations made.
ABOUT THE AUTHOR Dr. Sanjay Ahuja did his MBBS from UCMS/ Safdarjang Hospital /Delhi University/1980Batch (joining). He completed MD Ophthalmology from RPC, AIIMS in 1990. & then Senior Residency in Retina unit from RPC (AIIMS) (1990-93) under Prof Khosla, Prof Tiwari, Prof Atul Kumar & Dr. Lalit Verma. He worked as a Part time Retina consultant at MM EyeTech (Lajpat Nagar) with Prof Madan Mohan, Dr. Rishi Mohan & Dr. Indira Mohan from 1993 to 2007). He ran his private clinics at Parmanand Colony (Mukherjee Nagar) & Vijay Nagar (Near Delhi University) from 1993-2011 which have now been expanded into a four storey Eye Nursing Home at Parmanand Colony (Mukherjee Nagar) with his wife, Dr. Aparna Ahuja, who is also an Ophthalmologist from RPC/AIIMS (1990 batch joining). Dr Ahuja is currently working as: 1. Visiting Prof of Ophthalmology (Guest Teacher) at Dr. Sur Homeopathic Medical
College (SHMC) at Moti Bagh, IP University, Delhi Govt. 2. Head of Ophtha Deptt at Sant Nirankari Mandal (SNM) Charitable hospital at Nirankari Colony, Delhi-9. 3. Honorary senior consultant at Tirath Ram Shah Hospital (Near Tis Hazari courts). He is the co-author of 2 Books on Eye Disorders for Laymen with Dr. Aparna Ahuja. He received special cash prizes & certificates from ICMR, Delhi (2005) & Central Health Ministry, Govt. of India (2008). He has authored over 50 articles in Indexed & Non-indexed journals & Health magazines. Dr. Jatinder Bali Delhi Edited, Proofed and Published by Dr Jatinder Bali.
Preface to the Ninth Edition It is with great pleasure and pride that we present to you the ninth edition of this book, a culmination of years of experience and insight in the field of retinal diseases. Crafted by a seasoned retina specialist, this booklet aims to serve as a valuable resource for comprehensive ophthalmologists, offering practical tips and facts for addressing commonly encountered diseases in daily practice. Unlike traditional textbooks, this book is designed to be easily reable, providing succinct guidance on various aspects of retinal care. Drawing from extensive discussions and online forums, it offers a unique blend of expertise and real-world applicability, making it an indispensable tool for ophthalmic practitioners. While the transition from discussion to book may seem unconventional, it is our belief that this format preserves the dynamic and interactive nature of the content being
served, allowing readers to access valuable insights anytime, anywhere, on their mobile devices. We sincerely hope that you find this edition informative and insightful. Your feedback and suggestions are not only appreciated but eagerly welcomed, as they play a crucial role in shaping future editions and enhancing the quality of our collective knowledge. Thank you for your continued support and readership.. Dr Sanjay Ahuja Dr Jatinder Bali Delhi-2024.
Preface to First Edition This book is the result of a very popular series of tips discussed by a group of leading retina practitioners. It is very difficult to commit to paper the candid intangible observations in practising the art and the science of the subspecialty in Ophthalmology. Indeed, who could have done it better than Dr Sanjay Ahuja, who is himself a leading academician and practitioner. Tomes have been written about the retina but the books focussed on retinal practice on ground are few and far between. This book is unique because it handles the subject from a totally practical standpoint. It would have been easy to digress into the theoretical aspects but Dr Ahuja is a very disciplined writer and has demonstrated tremendous control over keeping this book totally focussed on practice. We hope the readers find the book interesting because in presenting it we have
taken risk and made a sincere effort to make it a useful advisor. We welcome your feedback. Dr Jatinder Bali, Author of “Pathological Ocular Angiogenesis and Macular Edema in Diabetes” and “Basics of Biostatistics: A Manual for Medical Practitioners” MBBS, MS, WHO Fellow in Vitreo-Retina, MBA (Operations Research) Chairman , ResearchCommittee, International Society of Manual Small Incision Cataract Surgeons, Library Officer, Delhi Ophthalmology Society, CMO, Narela Polyclinic,NDMC Formerly Asst DNB coordinator, Hindu Rao Hospital, Delhi Formerly Memb-Secy of Institutional Ethics Committee and Nodal Officer (Information Technology), Hindu Rao Hospital, Delhi Chairman, Subcommittee on Information Technology, Practice Automation and Clinical Information Systems of Delhi Ophthalmology Society Delhi. 2020
PRACTICAL TIPS Retina --Dr Sanjay Ahuja. Tip-1 Cross sectional image of conventional OCT scan is the B-Scan structural image. Consider it in 2 parts1. Inner retina with 3 hyper reflective layers (viz. From in to out- RNFL, IPL & OPL) is primarily affected in retinal vascular disorders e.g DR, CRVO.. 2. Outer retina with 3 hyper reflective layers (viz. From in to out- ELM, IS/OS junction or Ellipsoid layer & RPE) is primarily affected in ARMD, CSR... Tip-2 In Macular OCT image- To know whether correct FOVEAL cut has been obtained, check that OPL (Outer Plexiform layer) should join RNFL at one point in the foveal pit. Tip-3 In this COVID era, one may put the Cling film over & around the lens (towards
patient‟s side) of Fundus camera, Lasers, OCT or S/L without any significant compromise in quality. The film may be cleaned with alcohol swabs or changed for every patient. Tip-4 For proper evaluation of retinal diseases on OCT scan, always take the black & white (grey scale) printout. NOT the coloured print. Tip-5 In OCTA (OCT Angiography) no dye is injected (hence non-invasive) to study the retinal & choroidal vessels at various levels) The role of dye is taken up by the moving RBCs in capillaries. Tip-6 To differentiate whether it‟s a Red-free fundus photo (taken with green filter on fundus camera) or Fundus Autofluorescence photo (FAF), Look at the optic disc. It is dark/black on FAF but white on Red-free. On ICG also, disc is dark but white on FFA. Tip-7 Neovascular Membrane in ARMD can occur at 4 levels (OCT based) viz. Type-1: Sub-RPE (Occult CNVM)
Type-2: Sub-Retinal (Classic CNVM) Type-3: Intra-retinal (RAP or Retinal Angiomatous Proliferation) Type-4: is mixed type 1&2 Main treatment for all is Anti-VEGF Inj., however response to treatment & prognosis varies with type. Tip-8 While giving Intravitreal injection, always point the needle towards the CENTRE of the globe & never anteriorly, as it may damage the lens. Never try to visualise the needle tip while inside the globe. Always check his counting finger vision on the table itself before patient leaves the OT. Tip-9 Always treat the Diabetic maculopathy first before undertaking the cataract extraction, if possible. Control DM, HT & Renal condition. Do his FFA & OCT if possible. If CMT is >300 micron, always give Intravitreal Anti-VEGF Inj. Do focal laser if required (for focal thickening outside FAZ). Normal following is to undertake the cataract surgery after about a week of injection. However, if cataract surgery is not really urgent, good metabolic control should first be achieved along with stabilisation of diabetic retinopathy, especially if patient has
been seen for the first time, as maculopathy may still worsen. Tip-10 Never label the child or young adult complaining of B/L diminution of vision as a malingerer, even if his clinical examination is totally normal, as he may be having Heredomacular dystrophy like Stargardt‟s (F. flavimaculatus) or Cone dystrophy. These have totally normal fundus in early phases even though the patient is definitely symptomatic. Get his ERG, EOG & FFA. Tip-11 Standard Fundus camera clicks upto 50 degrees(*) in one shot. How much is 50*? 360*/75mm i.e equatorial circumference of globe =4.8* (5*approx). Thus 1mm=5* Optic disc diameter is 1.5mm= 7.5* Distance between Temporal disc margin & fovea= 15* Wide Field camera clicks 50-100* Ultra wide field camera (e.g. Optos) clicks 100-200* (i.e approximately 80% of retinal surface) Tip-12 In newborns, cornea is small & steep, hence
angle of viewing on Indirect ophthalmoscopy has to be more vertical rather than oblique unlike for adults. Tip-13 ROP simplified..... WHOM TO SCREEN.... 1. Preterm born at< or = 34 weeks 2. Birth weight < or = 2000gm 3. >34 weeks, If risk factors associated WHEN TO SCREEN... 1. At 3 weeks of birth, if GA is <27 weeks 2. At 4 weeks of birth, if GA is > or = 27 weeks 3. At least 1 exam before discharge from nursery. HOW OFTEN TO SCREEN.... 1. Every 2 weeks if no ROP 2. 2 days-2 weeks depending on zone & stage. WHEN TO STOP SCREENING... 1. Till retina fully vascularised. Temporal retina vascularises last. 2. ROP fully regressed 3. 40 weeks of post-menstrual age (=GA+Chronological age) if no ROP; as ROP almost never starts fresh after 40 weeks. WHOM TO TREAT..... 1. All with PLUS disease (dilatation & tortuosity of retinal vessels at post pole)
2. Stage-3 (extra retinal vascularisation) 3. APROP Zone-1 (around disc) is the most dangerous & Zone-3 (temporal retina) is the least. Tip-14 Doing just OCT scan in Diabetic maculopathy to pick up Central Macular Thickening & giving Ivit Anti-VEGF Inj is not enough. FFA or OCTA must be done to look for macular ischemia (broken FAZ on FFA), as it makes prognosis poor & is unresponsive to any treatment. AntiVEGF‟s treat edema & not ischemia. Tip-15.... Always click Red-free photo (with Green filter) on fundus camera to view retinal vasculature, retinal hges, RNFL defects & ERM as these are visualised better. Even pale lesions like drusen & exudates are seen better. Tip-16..... OCTA images are „en-face‟ images (i.e. facing forwards like standard fundus images) & NOT cross-sectional like OCT scans. Images are taken transversely at different levels/layers called Segmentation - done Automatically by machine or Manually
adjusted by operator on OCT scan image which is displayed simultaneously) Tip-17..... To differentiate Post cataract extraction CME & Diabetic Macular Edema (DME)- Edema in the former is Centered symmetrically around the fovea & there are no associated hard exudates or other DR changes. But both commonly coexist making differentiation difficult. On FFA, late disc leakage in CME may give a clue. On OCT, edema first starts in superficial retina in CME (entry of inflammatory cytokines from vitreous), while in DME, edema starts in deeper retina (breakage of inner & outer blood retinal barriers). CME generally resolves spontaneously in 80% in 3-12 months. Tip-18..... Eales‟ disease is a focal disease, only those areas affected by disease need to be lasered i.e. scatter laser only of ischemic/ neovascular areas; while Diabetic retinopathy is a generalised retinal disease, hence no role of focal/local laser (except in maculopathy) & if laser has to be done, it has to be full PRP & NOT the partial scatter of ischemic/ neovascular areas or just posterior pole scatter.
Tip-19..... FFA tells about the activity of retinal disease in form of dye leakage (i.e breakage of blood-retinal barrier), while OCTA can‟t tell whether neovascularisation is active or regressed i.e. disease is now inactive. Conversely, in OCTA, image doesn‟t get obscured by dye leakage & hence clear depiction of CNVM is possible unlike FFA. Tip-20.... IRMAs vs Retinal Neovascularisation (NV).... IRMAs unlike NV are broader in calibre, deeper in retina (hence have fuzzy margins & burgundy (purplish red) in color (not red of NV), don‟t occur on disc & don‟t leak on FFA. Both indicate ischemia. IRMAs may form from preexisting capillaries or new growths. Posterior hyaloid or ILM breach on OCT occurs only in NV. IRMAs may act as precursors of NV after they breach ILM & Posterior hyaloid. Tip-21..... On USG-B scan for proper posterior segment evaluation, Always do Transverse & Longitudinal scans Transconjunctivally (unless globe open) under topical anesthesia.
In Transverse scan, mark on the probe is kept parallel to limbus (perpendicular in Longitudinal). Each quadrant of globe has to be scanned systematically. In each quadrant, go from limbus to fornix while patient moves his eyes in other direction. Area in mark‟s direction is always projected superiorly in monitor. Axial scan may be done transpalpebral & in the last. Tip-22..... Excessive retinal venous „tortuousity‟ is the most important characteristic of venous occlusions (even if impending). No other common disease affecting retinal veins causes it, whether it be severe NPDR (cause venous dilatation, beading & looping), Ocular ischemic syndrome or hypertensive retinopathy. Rare exceptions are- Congenital venous tortuousity, Feeder venule of retinal capillary angioma & other angiomas, Sickle cell retinopathy. Tip-23..... Ellipsoid layer (IS/OS junction) if damaged on OCT scan indicates poor visual prognosis in retinal diseases. Ellipsoid layer is hyper reflective layer in outer retina just inner to RPE & COST layers but outer to ELM.
Tip-24..... Never fail to record BP in any patient with bilateral disc edema & retinal hges around the disc (Malignant HT) Tip-25..... In ischemic CRVO, Explain the poor visual prognosis clearly & risk of developing NVG (in 30%, in 1-6 months). Do OCT & give anti-VEGF/Ozurdex for CMT of >300 micron. Followup every month for NVI/NVA & fundus & OCT for CMT. If NVI/NVA developing, do PRP if feasible. Good quality FFA is possible only after 6 months. Tip-26..... Good fundus photo is the one which is evenly illuminated & focussed from edge to edge. Tip-27..... In Ophthalmic artery obstruction, vision is even worse than CRAO, almost PL negative & Cherry red macula is not seen, because Ophthalmic artery serves both Retinal circulation (via CRA) & Choroidal circulation (via Posterior ciliary arteries which supply choroid, outer 1/3rd retina & even optic disc.) Fovea has only outer 1/3rd retina.
Tip-28..... VKH may sometimes be confused with CSR(CSC). Both cause serous RD. Very important to differentiate as VKH needs systemic steroids which are contraindicated in CSR. In VKH unlike CSR, Retrolental/ vitreous inflammatory cells are there. On FFA in VKH, leaks are multiple & fill serous RD fully, disc being hyperemic, also stains in late phases. Neurosensory retinal detachment area NEVER fills completely with dye in CSR. Tip-29..... PACHYCHOROID (literally Thick choroid, Subfoveal choroid of >300 mn), becomes „Pachychoroid disease‟ (P) if assd. with 3 features viz. 1. Attenuation of choriocapillaris. 2. Dilated choroidal vessels (outer Haller‟s layer). 3. Progressive RPE atrophy & Neovascularisation. P. has many variants (more being added & includes CSC/CSR, PCV, etc.) which have „common Pathogenecity‟. P. is a new concept (2013) which came after choroidal imaging became easy with EDI (Enhanced Depth Imaging) OCT & SS (Swept Source) OCT. Both use longer
wavelength than conventional OCTs, thus penetrating deeper with reduced scattering & signal loss. Tip-30.... +90D fundus exam. steps... Theoretically field of view is 70 degrees (d),practically 35d only. Use 2-3 mm width of S/L. Aim light source prependicular or 10d offaxis. Place lens 1/2 inch from patient‟s eye. Pull back Joystick while looking through S/L till beam focused on retina. Make finer adjustments. Keep drawing chart „upside down‟ while noting findings (inverted image). Tip-31..... In PRP, laser spots should be greyish white (NOT dense white) ie moderate intensity, 1.5-2 burns width apart (spots auto-expand leaving 1-1.5), avoiding major retinal vessels, old laser spots, chorioretinal scars, retinal hges & vortex veins. Treat inferior areas first (may get obscured by future bleed). With 200-250 mn spot size (larger spots cause more pain, as it needs greater power), PRP needs 2500-3000 spots for completion.
Tip-32...... No leak on FFA in CSC/CSR (although SRF still present) may indicate: 1. Resolving CSC 2. Rule out „Optic nerve pit‟- depression in nerve which has a totally „different color‟ from optic nerve (neither pink nor white/pale). It is grey, black or even yellow, because of glial tissue. Tip-33..... On OCT scan print, to know whether it is the Right or Left eye..... RNFL is much thicker towards the disc. Hence if RNFL is thicker on our left side, it is the left eye image. Tip-34..... Unexplained (on clinical examination) deep seated U/L eyeache without proptosis but with ocular tenderness is highly suggestive of Posterior Scleritis (PS). Although rare, it is the most frequently missed or misdiagnosed eye disease. In PS, Inflammation is posterior to insertion of Recti i.e. Ora serrata. Associated with systemic immune diseases. Choroid, retina & optic nerve may get associated inflammation. USG B Scan is Typical. (Tip35).
Tip-35..... T- Sign on USG-B Scan is typical (almost pathognomonic) of Posterior Scleritis. Thick sclera of >2mm (along with thick choroid & fluid/edema in Tenon‟s capsule) forms horizontal limb of T. Vertical limb of T is in optic nerve (surrounding edema). T is echolucent (dark/black) on USG. Tip-36..... Is it T-1 or T-2 on MRI Scan? Remember T-2 loves H2O (water), hence cavities filled with water (liquid) eg Vitreous & CSF (in Ventricles) are white on T-2. Opposite with T-1. Fat, Melanin, blood & Aspergillus are whiter on T-1, hence Dermoid, Lipoma, Melanoma, Hgic Choroidal detachment & fresh hge anywhere in eye (3-14 days old) & Aspergilloma are whiter on T-1. Contrast (Gadolinium) makes everything more white on T-1, hence Fat-suppression must to study orbital diseases properly. T-1 delineates Normal anatomy better, hence grey matter of brain is grey on T-1 & white matter is white. All opposite with T-2. Tip-37...... Brolucizumab (Beovu, Novartis) is the latest Anti-VEGF approved by US-FDA (October‟19) for wet AMD. Dosing interval
is much longer (12 weeks), although 3 initial monthly loading doses recommended. Cost is ~1850$ (1.4 lakh INR). Not available in India. Tip-38...... Laser Retinopexy/Barrage laser.... Laser spots are placed 1/2 burn width apart (become confluent with spread of laser burn). 3 rows are applied all around the break. If small detachment is associated, extend spots till Ora. Maximum attachment strength is achieved in 2 weeks. Tip-39...... Don‟t order EOG in very young children or non-cooperative patients. EOG records electrical potential difference between front & back of eye, hence it requires patient to move eyes from side to side (electrodes are near inner & outer canthi) (15 minutes in dark & light alternately). EOG is the „best‟ for Best‟s disease (affected even in early stage also), while only in advanced stage in Stargardt. Normal value (Arden ratio > or = 1.8). Arden ratio term is now replaced by new (2017) term- „Light peak:dark trough ratio‟. Tip-40..... In a case of Rubeosis with a few retinal
hemorrhages, especially in mid-periphery, no or minimal venous tortuousity & no disc edema (unlike CRVO) ALWAYS think of Ocular Ischemic Syndrome. OIS occurs with >70% obstruction in Carotid/Ophthalmic artery. Usually U/L (unlike DR). Do FFA & PRP. Refer to physician & get Carotid Doppler (may need Endarterectomy). CRA perfusion pressure is low. Tip-41..... OCT Angiography (OCTA) printout basically shows 4 kinds of images.... 1. Fundus image (Enface structural image like any fundus photo) 2. Conventional OCT scan image (it is cross sectional- both horizontal & vertical) 3. OCT scan image showing Segmentation levels for OCTA scans, either Automatic by machine or Operator adjustable /Scrolleddepending upon area of interest. 4. OCTA Segmented scan images (Enface/frontal view) which grossly show 4 levels of Vascular planes viz. i) Superficial capillary plexus (RNFL/GCL level) ii) Deep capillary plexus (IPL & INL) iii) Avascular (outer retinaONL/ELM/Photoreceptor/RPE). Any vascularity at this level is Neovascularisation/abnormal.
iv) Choriocapillaris Tip-42..... If both Diabetic maculopathy (DDME) & PDR are present together (commonly happens), always treat Macular edema first by giving Anti-VEGF, followed by PRP starting after a week, as laser aggravates edema. If patient has both central DDME & focal edema little away with focal leak (from microaneurysm or capillaries). In addition to giving Anti-VEGF, focal laser should be done for this focal leak. Tip-43...... 3 most common causes of CNVM are: 1. AMD 2. Pathological Myopia- CNVM is small, type-2 (ie subretinal/ beneath NSR) minimally leaking & is closer to fovea. Foveal hge doesn‟t always mean CNVM. 3. Idiopathic- usually of classic variety (ie subretinal again). Treatment of choice for all is Anti-VEGF, however last 2 have much better prognosis than AMD. Tip-44...... Intraretinal cystic hyporeflective spaces on Macular OCT may indicate CME or ORT
(Outer Retinal Tubulation). VERY important to differentiate as the latter needs no treatment, while CME (eg in DR, AMD..) may need AntiVEGF. ORT unlike CME has typical thick Hyperreflective borders around cystic space & is located only in ONL of retina & CMT (central macular thickness) may be normal. ORT indicates chronic retinal disease (photoreceptors get folded outward, ie towards RPE) eg in n-AMD, HMD, diabetic maculopathy, etc. ORT indicates poor visual prognosis. Both CME & ORT may coexist. Optical coherence tomography showing outer retinal tubulation (indicated by white arrowhead) in a case of neovascular agerelated macular degeneration. White arrow indicates intraretinal cyst. Black arrow indicates subretinal fluid. Pic taken from Internet. Tip-45...... On FFA, In transmitted hyperfluorescence (ie window defect) hyperfluorescence starts in early phase, increases slowly but fades in Later phases unlike hyperfluorescence of leakage/ staining or pooling (eg in active CNVM, Leak of CSC, NVD/NVE, PED) which increases in later phases. For hypofluorescent areas, always look at
Fundus photo to differentiate CNP (Capillary non-perfusion) areas from Blocked fluorescence. Latter matches with extent of blocking material (eg hge). Moreover, CNP areas have normal capillary outlining unlike blocked fluorescence. Tip-46....... It‟s important to differentiate AMD from PCV (Polypoidal Choroidal Vasculopathy) as the latter has much better prognosis (if detected & treated early) with combined (as per EVEREST study) Anti-VEGF (treats fluid) & PDT (treats BVN & Polyps), while AMD has much poorer prognosis. PCV- has Multiple „sero-sanguinous PEDs & hard exudates‟ (neovascular & Hgic disease) in old age (50-65 years). Commoner in Asians. Mimics type-1 AMD (sub-RPE/occult CNVM). Question whether PCV is a variant of AMD is unsettled? Polyp & abnormal BVN (Branching choroidal Vascular Network) are pathognomonic features arising from inner choroidal vasculature (cause ?). Unlike AMD, PCV has/is.... 1. No associated druse. 2. More often peripapillary or multifocal (Macula more commonly involved in Asians) 3. Anti-VEGF alone are not effective unlike
in AMD. 3. Fundus: Reddish-orange round polypoidal lesions seen (if large). 4. Retinal hemorrhage is generally „large‟. 5. FFA- only occasionally detects polyps. Basically to rule out other causes of exudation & CNVM. 6. OCT- Polyps seen as elevation from RPEBruch‟s. Cystic spaces less common (hence better prognosis than AMD). „Double layer sign‟ is characteristic at PED margins (separation of Bruch‟s from either RPE or choroid). 7. ICGA is MUST & confirmatory. Polyps at termination of BVN seen better in mid phases with fading centre or late staining or leaking walls in late phases. Tip-47..... Characteristic FFA picture in common Optic nerve diseases.... 1. Optic pit- Early hypofluorescence & late staining of pit, because of absence of vessels but presence of glial tissue in pit. 2. Papilledema- Disc capillaries dilated & leaking. Late staining of disc. 3. AION- Differential disc capillary filling in superior & inferior half. 4. Disc drusen- Autofluorescent before dye injection. Late staining
5. Neuroretinitis- Dilated & leaking disc capillaries. Macular fan/star is from leakage of disc capillaries & NOT macular capillaries. 6. Leber‟s hereditary optic neuropathyDilated disc capillaries bot NOT leaking. Tip-48..... How to identify RNFL defects on Fundus exam.... 1. Normal RNFL is brighter & has striations (stripy textured pattern). Brightness & striations reduce with damage. 2. Observe parapapillary vessels. Typically, they appear fuzzy. With RNFL damage/loss, their borders become more defined. About RNFL defects on fundus exam.... 1. Not specific to glaucoma (any optic neuropathy/ ganglion cell loss) can cause them. 2. Better seen in Red free photos (green filter). 3. Occur more often in NTG & early rather than advanced glaucomas. 4. Could be localised wedge shaped or diffuse. Former is easier to identify than diffuse. 5. Associated disc hge common (in wedge defects). 6. Commoner in superior & inferior temporal regions.
7. Help in pre-perimetric diagnosis of glaucoma. Tip-49...... Typically, early postoperative endophthalmitis unlike non-infective (eg TASS- starts earlier-within 24 hours, limbus to limbus cornea edema, no posterior segment involvement, responds to steroids) is characterised by- pain (most significant but missing in 1/4th), lid edema, congestion, chemosis & more AC reaction as compared to that expected by surgeon (For treatment, see Tip-50). Chronic postop endophthalmitis (presenting after 6 weeks) is mostly caused by Propionibacterium acnes followed by Fungal or Staph albus. Pain & inflammation may respond to steroids initially but recurs requiring Intracapsular Vanco, Radical PPV with capsule & IOL removal. Tip-50...... Management of early (<6 weeks) Postcataract endophthalmitis (Es). Broad outlines.... 1. Always consider Es, if early postoperative patient calls U c/o PDR ie Pain, D/V & Redness. 2. Western literature says organisms in 90% are Gram +ve bacteria (70% Coagulase-ve
Staph ie albus). Indian studies blame Gram - ve equally. 3. Look at the Disc & Retinal vessels & grade Fundal glow with I/O (Whether both, only disc or none seen) for follow ups. 4. Take anterior vitreous needle tap (26 G with TB syringe, 3.5 mm from limbus) slowly. If dry, take vitreous biopsy with cutter. Gram stain & c/s (preferably for all 3- aerobic, anaerobic & fungal). For PCR, inform lab about suspected organism(s). 5. IVit inj of Vancomycin (1mg in 0.1ml) & Ceftazidime (2.25mg in 0.1 ml) separately, 3.5 mm from limbus. or Amika (0.4mg in 0.1ml) instead of Cefta. 6. Moxifloxacin & Concd Tobra (1.4%, 5ml of 0.3%Tobra + 2ml of 80mg Tobra Inj) eyedrops every 1 hourly. Homide/Atropine. Anti glaucoma, if required. Start Topical steroids after 24-48 hours if condition stable/ improving (Not if fungal suspected) 7. IV Ciprofloxacin (200mg BDx 2 days) followed by oral 750mg BD x10 days. Cipro more broad spectrum than Moxi. Moxi more effective against MRSA Staph but less against Gram-ve. 8. Repeat IVit Inj at 48 hours if condition stable but no significant improvement. If deteriorated, go for PPV. 9. Improvement means Symptoms reduced,
less AC reaction & glow improved. 10. As per EVS (Es Vitrectomy Study), Go for early PPV, if VA is only PL. 11. EVS applicable to early postop Es only & NOT to Chronic (>6 weeks) postop, post traumatic or endogenous Es. 12. Treat wound leak, vitreous incarceration, etc if any. 13. Coagulase-ve Staph has better prognosis than Coagulase +ve Staph & Gram -ves (eg Pseudomonas). 14. Prognosis worse with post IVit Inj Es (organism‟s direct entry into vitreous). Tip-51.... Non-contact Fundus biomicroscopy..... 1. S/L can‟t show beyond anterior 1/3rd of eye as cornea acts as high plus lens (i.e. converges), another plus lens placed before it, makes it an astronomical telescope. 2. Powers used... +60 to +130D (commonly +78 & +90D). Give real, Inverted & laterally reversed aerial image. 3. With increasing power of lens... i) Working distance from cornea decreases. ii) Magnification decreases iii) Field of view increases. iv) Work better even with smaller pupil Eg +90D provides 74* static (dynamic is when patient is asked to move the eyes to increase the field) field, 0.76x magnification
& 7mm working distance from cornea unlike +60D (68*/1.15x/13mm). 4. +60D is for detailed disc exam & 90D is „Harfan-maulla‟). Buy 90D if cheap, single lens inventory planned. 5. Volk also makes Branded lenses like „Superfield‟ (95*/0.76x/7mm) & „Digital wide field‟ (103*/0.72x/4.5mm). Digital (HD/High Definition) lenses have improved shapes & high index glass. They are the best buys but costlier. 6. Optics of S/L also matters. 7. Single use (disposable!) lenses also now available. Tip-52..... Hyper reflective lesions on OCT Macula are- 4H‟s.. Heme (blood), Hard exudates, Healed scars & Hyperpigmentation. Also Neovascularisation. Hyper reflective lesions appear red on colored scan & white on grey scale. Tip-53...... Preretinal hemorrhage (hge) term is loosely used for both „Subhyaloid hge‟ (SHH i.e. under posterior hyaloid) & „Sub-ILM hge‟ (SIH), although SIH is Intra & not preretinal. Clinical differentiation is difficult, but may be possible.....
SIH unlike SHH has.... 1. Glistening reflexes from ILM on fundoscopy. 2. Sharply demarcated & dome shaped. 3. Doesn‟t change position with change in head posture. 4. More often Macular. 5. OCT of upper clearer area in patients with partial PVD, 2 distinct hyper reflective membranes may be seen (of ILM & Posterior hyaloid membrane). 6. Takes longer to absorb. 7. Less safer to do „YAG posterior hyaloidotomy‟. Normally done with 3- mirror near inferior edge of hge away from vessels & fovea; start with 5 mJ, increase by 1 mJ till perforation visible. 8. Needs surgery more often. 9. Definite differentiation may be possible only during Vitrectomy & ILM staining. Tip-54...... In a patient with simultaneous pre retinal, Intraretinal & subretinal hemorrhage, always think of Retinal Artery Macroaneurym (RAM). Hge is NEVER subretinal in DR. RAM is/has... 1. Acquired, focal, aneurysmal dilatation of usually temporal 2nd order retinal arteriole. 2. Average size =200mn (Microaneurysm =10-50 mn)
3. Associated HT common (75%). 4. May leak (edema & exudation) or rupture (hge at ANY retinal level). 5. Treatment- Observe, if asymptomatic (spontaneous resorption common). Direct Laser (large spot size) or Anti-VEGF. For submacular hge- PPV, pneumatic displacement +/- TPA. Tip-55..... In a case of Retinal vasculitis, ALWAYS check, which vessels are mainly involved... 1. Phlebitis (venous)- in Eales, Behcet‟s, TB, Sarcoid, Pars planitis, Multiple sclerosis, HIV. 2. Arteritis- in ARN (Acute retinal necrosis in HSV or HZV), Systemic vasculitides/SV (SLE, PAN, Wegner) & Idiopathic. If associated fundus finding in vasculitis is... 1. Cotton wool spots- think of SV 2. Necrotising retinitis- Toxoplasmosis, ARN, CMV. 3. Frosted (ice crystals like deposits on vessel walls) branch angiitis- in Idiopathic, Lymphoma or Leukaemic infiltrates, SV, Toxoplasmosis, HIV & HSV. 4. BRVOs- in all causes of Phlebitis (vide supra ut ante dictum est). Tip-56...... Optic Nerve Head Drusen (ONHD) may be
confused as disc edema or Papilledema. To differentiate on fundus exam. ONHD is/has... 1. Pinkish or yellowish disc & NOT hyperemic or having hemorrhages or telangiectatic vessels. 2. Peripapillary nerve fibre striations are not obscured. 3. Vessels of disc are not dilated & don‟t get obscured as they traverse the disc margin. 4. Disc margins may have lumpy appearance, if druse are superficial. 5. Spontaneous venous pulsations may be present. 6. Edema is always superficial while druse may be deep. 7. Usually asymptomatic. 8. Anomalies of overlying disc vessels are common. USG-B Scan is the most important investigation for buried drusen, being seen as highly echogenic foci (ONHD are calcified extracellular axoplasmic proteins). Tip-57...... Incidence of Lattice degeneration in Degenerative/Pathological myopia (PM, usually >-6D) is NOT more than in Simple myopia. Posterior staphylomatous elongation in PM rather than whole eye enlargement doesn‟t increase chances of
Lattice. Following changes occur only in PM... 1. Myopic crescent-Hallmark. Usually temporal 2. Lacquer cracks in Bruch‟s. May cause subretinal hge with or without CNVM. 3. Fuch‟s spot- submacular hyperpigmentation indicating old hge or CNVM. 4. PVD & RD. 5. Posterior staphyloma 6. Geographic/ chorioretinal atrophy in posterior pole or anywhere in retina. 7. CNVM- Type-2/Subretinal/Classical. May sometimes remain spontaneously stable. Much better prognosis than in AMD. Tip-58.... In some cases of CSC/CSR, there is large neurosensory retinal (NSR) detachment of posterior pole. This leads to gravitational shift of fluid to inferior retina, ultimately leading to „gutter‟ formation (RPE tracts) of RPE alterations extending inferiorly to have a flask, tear drop or dumb-bell shape. Tip-59..... When to treat Retinal Lattice degeneration (LD)?... LD with or without atrophic retinal holes per se doesn‟t need any prophylactic treatment
except in special situations. As per AAO recommendations (2019), these are.. 1. Acute Symptomatic LD (fresh flashes/floaters) with Horse shoe tears. 2. Acute PVD with vitreous/ retinal hge or visible vitreo-retinal traction (on contact fundus biomicroscopy) However, most retina specialists treat in following conditions also (although controversial).... 1. LD in fellow eye of RD (Retinal detachment). 2. Family h/o RD 3. Those undergoing cataract (increases PVD chances, the main CULPRIT for tears/RD in LD, because of strong vitreoretinal adhesions at lattiice edges) or LASIK surgery. 4. Poorly compliant patient 5. Those predisposed to contact traumas. 6. Associated SRF 7. Very large number of lattices, especially if in superior quadrants 8. Radial and especially perivascular lattices. 9. Equatorial or more posterior lattices Identifying LD... Novices confuse it with Ora sometimes. (Trace all its borders). For LD, lattice (white criss-cross) lines are NOT must (rather lesions may have
pigmentation/whitish flecks/ red craters/snow flakes or RPE atrophic spots along with retinal thinning; However its borders are SHARPLY demarcated (abruptly ending) from surrounding normal retina. If treating LD, surround by 3 rows of laser spots especially anterior margins. Tip-60.... Majority of Intraocular malignancies are metastatic (majority to choroid, being highly vascular, usually non-pigmented & poorly circumscribed with/out exudative RD) most of which ophthalmologists never come to see. Breast CA (carcinoma) metastasis (commonest in females) tends to be B/L & multifocal, while Lung CA (commonest in males) metastasis tends to be U/L & Unifocal. Tip-61..... ALWAYS think of 5 following retinal diseases other than AMD in a patient with Macular hges, edema & subretinal exudates.... Abbreviated by an Acronym- MICRA.... 1. Macroaneurysm (RAM) 2. IPCV
3. CNVM ((idiopathic) 4. RAP (Retinal Angiomatous Proliferation) in MacTel/PFT. 5. Adult Coats‟ Tip-62..... Hard & Soft Facts about Drusen (D)... -Hallmark of Dry (Non-exudative) AMD & are degenerated RPE products? -Sub-RPE or Intra-Bruch‟s pale yellow deposits -could be Small/hard(<63mn), medium or Large/Soft (>125mn) -Calcified D. are yellow & glistening -„Large/soft D & Focal hyperpigmentation‟ of RPE form risk factor (& not small/hard D) for CNVM, hence need AREDS2 formula (reduces risk of advanced ie Geographic & Neovascular AMD by 25% over 5 years) orally. -Usually asymptomatic or may cause impaired contrast/distortion/ poor light adaptation/ reading difficulty. -May resolve or increase (ie NOT static) -Large/soft D may confluend causing Drusenoid PED. -FFA- Hard D: Early Hyperfluorescence due to overlying RPE atrophy, while soft show early hypo & late hyperfluorescence. No leaks. -Intermediate AMD is Medium D with RPE
alterations or 1 or more Large D. Tip-63..... Most closely mimicking disease of Diabetic retinopathy is „Radiation Retinopathy‟ (RR) which has exactly similar fundus picture. RR.... -Usually delayed by 6-36 months of unshielded radiation (external beam or plaque brachytherapy) ->5000 rad (50 Gray) is most offending ((although no definite value can be given). -Commonly after CA nasopharynx, Pituitary tumor, etc -Walls of capillaries & small vessels of retina get damaged. -Treatment similar to DR viz. Laser & AntiVEGF. Radiation optic neuropathy occurs with similar doses & is similarly delayed, while Cataract occurs more frequently, early & with lesser doses (500 rads). Tip-64...... Treatment of Age-related Macular Degeneration (AMD).... 1. Dry (Non exudative) with Hard/small druse & non-geographic or geographic atrophy- No role of AREDS2 formula. Stop smoking. Control weight & HT. Issue Grid. 2. Intermediate AMD (Medium druse +
focal hyperpigmentation or 1 or more soft/large drusen (>125 mn) - Give AREDS2 formula drug. 3. Wet (Exudative) AMD- Monthly Ranibizumab (US-FDA approved) /Bevacizumab (off-label) or Bimonthly Eylea. Thermal Laser for extrafoveal CNVM (as per MPS of 1980). 60% recurrence (hence many prefer Anti-VEGF). PDT- presently used only as adjunct (with reduced fluence/energy) with Anti-VEGF. Works best for PCV. Submacular hge- poor results with surgical evacuation. Pneumatic displacement + TPA (Tissue plasminogen activator) inj. (lyses clot) may help. Tip-65...... As per SUN (Standardisation of Uveitis Nomenclature, 2004) by IUSG (International Uveitis Study Group)- Intermediate uveitis (IU) is Vitritis with peripheral retinal vascular sheathing or/& macular edema due to any cause (vide infra). While Pars planitis (PP, constitutes 70% of all IU) is a specific, idiopathic (NOT secondary to any systemic/ocular disease) type of IU with Snowballs in inferior peripheral vitreous or Snow-banking on inferior peripheral retina (both are
manifestations of inflammation) Acronym for known causes of IU- SMILE.... Sarcoidosis, Multiple sclerosis, Inflammatory bowel disease, Lymphoma (2/3rd primarily from CNS), Etc (includes TB, Toxocara, etc.). Sarcoidosis, PP & TB are most important. Treatment for Pars Planitis required (in 70%) only if associated with Macular edema (occurs in 50%) causing diminution of vision or Peripheral retinal neovascularisation. Treatment includes.... 1. Periocular steroids -mostly subtenon Tricort/Triamcinolone acetonide 0.5-1 ml of 40mg/ml. Repeat at 6 weeks. Check for steroid responder- Prednisolone drops qid x 2-3 weeks (Not confirmatory). 2. Systemic steroids- if PP is B/L & severe. 1-1.5 mg/kg/day Predni x 4 weeks. Taper as per response. 3. Intravitreal steroid implant- Ozurdex (0.7 mg Dexamethasone)/Allergan/ INR 26,000/ (MRP-36000/) 4. Immunosuppressives- Methotrexate safest (even in child) & most tried. Cyclosporine next alternative. 5. Laser (Cryo, only if Laser not possible) for peripheral neovascularisation. Tip-66...... CSC/CSR has been strongly associated with
use of steroids, even if given in the form of skin creams, inhalers, joint injections, oral or parenteral. It must be discontinued. Tip-67..... Spectralis (HRA) & Optos use Confocal scanning laser ophthalmoscope (CSLO), providing high resolution fundus images, unlike conventional Fundus cameras. CSLO uses Diode laser beam scanning in Raster (transverse) fashion & improves patient‟s comfort also by using less bright light. Confocal imaging is enface (frontal/transverse) imaging at one plane eliminating background information which otherwise degrades the image. Both Spectralis & Optos also provide Multimodal fundal imaging (MMFI). MMFI is combining different imaging modules to diagnose or manage single retinal disease & may include.... Fundus photography, Wide field & Ultrawide field imaging, Red free, Stereo photography, Infrared reflectance, FFA, FAF, ICG, SD-OCT, SS-OCT, EDI-OCT, OCTA & Adaptive optics SLO. Blue colour photography is best for retinal surface (ERM, RNFL), Green for hges & Infrared (less absorbed by blood & pigment) for RPE & Choroid.
Tip-68..... Posterior segment/ Macular evaluation in Cataract patient.... Especially if vision (after best correction) not COMMENSURATE with cataract & Fundus examination is difficult.... -Accurate PL & PR. Check for yourself. -Try I/O (brighter light) -Pupillary reactions -Maddox Rod (MR)-patient looks at penlight at 1 foot through MR. Reports break/distortion. -Laser Interferometry-Fringes projected through clear area. Overestimates vision, especially in amblyopes. -Entoptic phenomena (Purkinje)- penlight is rapidly moved on closed lids creating Fundal vascular tree perceived by patient. -Potential visual Acuity Meter (PAM)- Miniature Snellen chart is projected on the macula. -VEP- Amplitude is for macula/ visual acuity & Latency is for Visual pathway (includes optic nerve) -USG-B scan -Focal ERG -OCT rarely feasible. MR, LI, PAM & Entoptic are Subjective & need some clear area in cataract.
Tip-69..... Classical presentation of Ocular Toxoplasmosis (OT) is active chorioretinitis (necrotising) adjacent to healed pigmented scar (punched out) with (may be absent in immunocompromised) overlying vitritis „Headlight in fog appearance‟. Facts about OT... -most common cause of posterior & infectious uveitis. -Now acquired infection considered equally important (earlier always believed to be reactivation of congenital focus) -commonly asymptomatic (peripheral, selflimited, requiring no treatment) -Granulomatous or non-granulomatous & Recurring (especially in first year). -Any positive titre of Antibody is useful. Negative titres rule it out (exceptionimmunocompromised). IgM titre indicates recent infection. PCR also available for aqueous/vitreous tap. -Treatment required only if fovea, large retinal vessel (occlusion/hge) or optic nerve threatened or already involved actively or immunocompromised or if patient is child. -Triple therapy of SPP- Sulfadiazine+ Pyrimethamine+ oral Predni is best. Folinic acid added to counteract side effect of Pyrimethamine.
-Alternately Tab Cotrimoxazole (Trimethoprim+ Sulfamethoxazole) 2BD x 4-6 weeks (especially used to prevent recurrences) -Clindamycin for Sulfa allergic patients. Tip-70...... In contrast to Ocular Toxoplasmosis (OTP), another vitreo-retinal disease (less common) is Ocular Toxocariasis (OTC). (See Tip-69) OTC unlike OTP is/has.... -Always unilateral -Always acquired (Feco-oral from cat/dog feces). Usually children. -More often peripheral retina involved -Non-necrotising, granulomatous, FIBROTIC disease (vitreous membranes & tractional RD) -Chronic “pseudo-endophthalmitis” picture may present as Leucocoria (Pseudoglioma). -Diagnosis mainly clinical or ELISA for Ab. Eosinophilia in Systemic Toxocariasis (Visceral Larva Migrans/VLM). -Treatment- Steroids (for active vitritis) & Surgery (PPV to remove membranes & traction) are the mainstay. Tip-71...... Epiretinal membrane (ERM)..... -Synonyms- Cellophane maculopathy,
Surface wrinkling retinopathy or Macular pucker. -Commonly idiopathic (after 60 years) or Secondary to many Retinal diseases -1/5th are B/L -Starts with PVD & ILM disruption stimulating Glial (Muller) cells causing Fibro-cellular (but Avascular) proliferations. -Asymptomatic, if thin, as in majority. -Appears as translucent, shiny macular surface on 90D exam when young, but gradually opacifies. -May cause CME, TRD or Spontaneous RELEASE (resolution). -OCT is Gold standard for diagnosis, progress & prognosis. To differentiate from PVD on OCTUnlike ERM, PVD is usually greatly separated from retina & is thin, patchy & less reflecting. -Surgery- PPV with peeling & removal if VA is less than or equal to 6/18 or disturbing metamorphopsia present. Expect improvement over 3-6 months if not longstanding & Ellipsoid layer is intact on OCT. Recurs in 1%. Tip-72...... Meaning of Zumab in Ranibizumab/Bevacizumab..... MAB is an acronym for Monoclonal