Interpretation of SD-OCT Gella Laxmi 2009PHXF013P

How to go about…. Interpretation should proceed sequentially from vitreous towards choroid Evaluate each layers

Gray scale or conventional colors? Gray scale images – qualitatively superior Color images – misleading

Reflectivity Hyper reflective Lesions (Red )Hypo reflective Lesions (Black) (Fluid) ME PED SRF Fovealschisis ERM CNVM DRUSEN HE

Thickness Increased (edema, CNVM) Decreased

Morphology “Missing" retina"Extra" retinal tissue

Before advising OCT Answer 2 questions... “Why OCT in this case?”“What to look for in OCT?”

Diabetic Macular Edema Classify (FFA better) To R/O Foveolar detachment To R/O VMT ( Difficult clinically) Post treatment follow up Swelling – Focal /Diffuse / Cystoid Hard exudates Foveolar detachment Status of posterior hyaloid CWS, Hemorrhage

OCT classification of macular edema Diffuse Retinal Thickening (DRT) Cystoid Macular Edema (CME) Neurosensory Detachment (NSD) Schitic Retinal Thickening (SRT)

Macular Hole Confirmation Staging Surgical planning Patient education FTMH LMH VMT What to look for?Why OCT?

OCT Staging of macular hole Stage 1B (Full thickness pseudocyst) Stage 2 (Partial opening of pseudooperculum focal Vitreous attachment ) Stage 3 (Operculated FTMH Vitreous traction released) Stage 4 (With complete PVD) Post surgery

Surgical prognosis Preoperative macular hole configuration and size determined by OCT showed good correlation with anatomical and functional outcomes after surgery

HFF > % PRIMARY CLOSURE HFF = % PRIMARY CLOSURE HFF < Poor closure rates

ARMD Diagnosis - Dry or Wet Response to treatment Drusens Lipofusin deposits Bumpy RPE High reflective Normal inner retinal layers No shadowing

Types of PED Fibrovascular Serous Hemorrhagic Drusanoid

Types of CNVM Occult Classic Intraretinal fluid is associated with the presence of neovascular membrane Disruption of RPE band Irregular thickening below RPE CNVM not adequately visualized Optical shadowing by detached RPE Continuous RPE band Well defined, Hyperreflective fusiform thickening above RPE Marked, posterior shadowing

Central Serous Retinopathy RPE defect SRF Cystoid spaces Foveal atrophy/thinning Subretinal fibrin CNVM Compare the reflectivity with vitreous Granular outer segment in chronic cases

Parafoveal Telangiectasia Cystic spaces Minimum/ moderate thickening Defect at the level of photoreceptor layer Intraretinal high reflective areas causing shadow (migrated pigments)

OCT in ERM and VMT Confirmation Topographic localization Surgical planning R/O coincidental pathology like macular hole /pseudohole

References M Brar, D-U G Bartsch. Colour versus grey-scale display of images on high- resolution spectral OCT. Br J Ophthalmol. 2009; 93: Brian Y. Kim, Scott D. Smith, et al. Optical Coherence Tomographic patterns of Diabetic Macular Edema. Am J Ophthalmol. 2006; 142; S Ullrich, C Haritoglou, C Gass, M Schaumberger, M W Ulbig. Macular hole size as a prognostic factor in macular hole surgery. Br J Ophthalmol April; 86(4): 390–393. Kusuhara S, Teraoka Escano MF, Fujii S et al. Prediction of postoperative visual outcome based on hole configuration by optical coherence tomography in eyes with idiopathic macular holes. Am J Ophthalmol 2004; 138: 709–16. Lisandro M Sakata, Julio DeLeon-Ortega et al. Optical coherence tomography of the retina and optic nerve – a review. Clinical and Experimental Ophthalmology 2009; 37: 90–99.