Course # Getting to Know Your OCT

Transcription

1 Course # 140 Getting to Know Your OCT

2 Course Title: Lecturer: Getting to Know Your OCT Brad Sutton, OD, FAAO IU School of Optometry Financial Disclosures No financial disclosures Optical Coherence Tomography-OCT Has changed the way the eye is examined & treated. Has revolutionized the diagnosis & therapy of eye disease. Allows for earlier and more sensitive diagnosis. Allows for better understanding of disease mechanisms OCT 1991 James Fujimoto at MIT Original research instrument 400 A-scans / second Current SD-OCT: around 27,000 to 50,000 A-scans / sec Current Swept Source-OCT up to 249,000 A-scans / sec. Commercial units about 100,000 per second OCT angiography So how did we get here? OCT First commercial OCT company in 1992: Advanced Ophthalmic Devices Sold on August 27 th of 1993 to Humphrey- Now Carl Zeiss Meditech First commercial OCT from them in 1996 OCT By 2008, Zeiss had sold 10,000 OCT s Now, there are 8 companies that manufacture OCT s commercially 1

3 Different Companies and Prices OCT Stratus: $53,000 (lower refurbished) Cirrus: $70-75,000 ( new unit with SD- OCT, fundus camera, and FAF?$) OptoVue (I Vue and RTVue): $40,000 - $60,000 Heidelberg Spectralis: $80,000: FAF Topcon: has fundus camera, OPTOS Some have no normative data in vivo histology Working mechanism: similar to B scan (optical vs. acoustic reflectivity) but uses infrared light Resolution: < 10 microns (Stratus OCT III), 3-5 microns with SD and SS technology Different optical reflectivity in various tissue structures: false color map. Often best to view in black and white for fine detail Courtesy Dan Hammer, PSI Image quality Poor signal strength equates to unreliable readings, only use 7 and above Images and reliability can be negatively impacted by media opacities, high myopia, patient movement, highly abnormal disc sizes, and segmentation errors (very important!) Beware red disease, split NFL bundles for example Average RNFL loss of about 1 micron / year Importance of normative database Cirrus normative database Typically take demographic factors in to account, but not refractive error. This can be very important with high myopes, who will have thinner NFL than their counterparts with equal demographics Composition of normative database also very important 284 individuals Age 18 to 84 Refractive error to -12:00 43% Caucasian 24% Asian 18% African American 12% Hispanic 1% Indian Small amount of others combined 2

4 Spectral Domain OCT Cirrus OCT Easier to use. Faster (1/75 the time it takes TD). Greater resolution (3-5 Microns vs.10) Larger scan area (6mm X 6mm). Can create three dimensional cubed images. Precise registration (can follow the exact retinal area each visit). 3 D retinal layer segmentation maps. Focus range of +/- 20 diopters: Loaded at original patient entry EDI Cube ERM (different patients) with Stratus and Cirrus OCT AMD LSLO fundus image with overlay of retinal thickness map High Myopia with ICSC 3D layer segmentation maps provide detailed visualization of histology and pathology Precise location of raster lines indicated on LSLO fundus image 3D retinal thickness map 3D segmentation of RPE layer 3D segmentation of ILM and RPE layers Courtesy of Bascom Palmer Eye Institute, Miami, Florida Courtesy of Bascom Palmer Eye Institute, Miami, Florida 3

5 High Myopia with ICSC LSLO fundus image with overlay of retinal thickness map 3D layer segmentation maps provide detailed visualization of histology and pathology 3D retinal thickness map 3D segmentation of RPE layer 3D segmentation of ILM and RPE layers Courtesy of Bascom Palmer Eye Institute, Miami, Florida AMD FAF PIL Very important! Line seen at junction of inner and outer segments of the photoreceptors Extremely useful for evaluating disease state and visual potential Ophthalmology calls it the ellipsoid line or ellipsoid zone Swept Source OCT Adaptive Optics (Images courtesy of Dr. Steve Burns) Twice as fast (twice as many A-scans / second) as SD OCT Allows for wide field imaging (12mm vs. 6-9 mm). Easily gets ONH and macula in the same scan Longer wavelength of light, so can image much more effectively through media opacities, and penetrates much better in to the choroid (2.6 mm depth vs. 2.3mm) 4

6 Quantifying edema : BRVO S/P Intravitreal Kenalog Injection x 2 mos 20/20- Macular edema returns Central Retinal Vein Occlusion Another Injection 20/20 20/70 20/25 Pars planitis with chronic CME 20/80 S/P 2 Intravitreal Steroid Injections 20/30 Diamox! 5

7 What else is going on? Good eye? RP WITH CME RP WITH CME OCT Post-op CME Vitreoretinal Interface Disorders Idiopathic Epiretinal Membrane Vitreomacular Traction Syndrome Idiopathic Macular Hole Full thickness Macular Hole Macular hole sizes Small <= 250 microns Medium microns Large > 400 microns Horizontal diameter at narrowest point 6

8 New grading system ERM VMA with no change in foveal contour: Stage 0 VMT with disruption of foveal contour: Stage 1 VMT with small or medium FT hole: Stage 2 VMT with medium or large full thickness hole: Stage 3 Any full thickness hole without VMT: stage 4 Lamellar hole Psuedohole from ERM Membranous growth of glial cells on retina surface Can be asymptomatic or very bothersome Metamorphopsia is common More common after PVD Tractional macular holes, cysts, CME, neurosensory RD s; retinal and choroidal folds, etc. Rerm ERM ERM + Cystoid Edema ERM with Macular Edema ERM Cysts ERM lemon drops ERM Neurosensory RD 7

9 ILM fracture ERM with psuedoholes 20/30 Lemon drops ERM with lamellar hole ERM OS Full Thickness Macular Hole ERM Macular Holes: 70 Y/O female Full thickness macular hole & ERM- OS BCVA 20/400 Pseudohole 20/25- OD 8

10 Pseudohole Macular hole repair Posterior hyaloid Photoreceptors 20/25! VMTS 3yrs later 20/20- VFTS with early hole Foveal detachment 9

11 VMTS & ERM Posterior hyaloid ERM VMA on an ERM VFTS spontaneous resolution after 3 months Jetrea / Ocriplasmin Effective at breaking VMA about 26% of the time in clinical trials Costs $3000-$4000 per injection Reports of decreased visual function after injection, usually not permanent 10

12 Jetrea Jetrea Factors that increase success in real world settings (Ophthalmology Times on-line) to about 50%... VMA < 1500 microns in diameter Age < 65 Full thickness macular hole present Phakic eye No ERM If PIL line disrupted at one week after injection (recovers by one month), then 75% chance of success This PIL disruption may correlate with reports of temporary reduction in visual function VFTS VFTS Full thickness hole OD, VMTS OS 11

13 Anti-VMA! Macular Hole Formation Attached Operculum Macular Hole Posterior Hyaloid Operculum Cystic spaces OS Stage 4 Macular Hole Large Stage 4 Hole Macular Hole 12

14 Central Serous Retinopathy CSR with PED ICSC with LEMON DROPS Old ICSC ICSC has abnormally thick choroid on SD OCT EDI: Normal is 250 microns. drops of water on a windshield SD-OCT 13

15 SD-OCT SD-OCT Macular Degeneration Drusen- Dry AMD Drusenoid PED- Soft Drusen 14

16 SD PED PED VA= 20/70 PED Subretinal fluid.or is there something else? Same concept CNVM Miscellaneous Retinal Conditions S/P Avastin injection- What s new? 15

17 Chloroquine maculopathy Chloroquine OCT Plaquenil toxicity: Flying Saucer Sign Medullated Nerve Fibers? Retinal Detachment Bullous RD Macula off 16

18 S/P RD surgery 6 Mos. 20/40 Macula off RD PDR with traction RD Development of Foveal Retinoschisis Foveal Retinoschisis Another Patient Foveal Retinoschisis OS OD 17

19 hypotony Solar Maculopathy Choroidal Folds Focal defect in PR outer segments and RPE Solar Maculopathy Solar maculopathy Solar maculopathy Courtesy Dr. Jerome Sherman 18

20 Adult Vitelliform Also Adult Vitelliform Best s dystrophy Cone dystrophy Cone dystrophy OCT IJXT with ILM drape 20/40 ILM drape 19

21 ORT s ORT s Optic nerve head and glaucoma Use of GCC analysis with glaucoma 20

22 GCC analysis VF OU GCC and VF Loss comparison Stroke and GCC loss Stroke and GCC loss # 2 Stroke and GCC loss #2 21

23 Optic Nerve Pit Optic Nerve Pit Pit? ONH Colobomas ONH Coloboma OCT Papilledema- IIH 25Y/O female Dg: IIH Diamox Tx 22

24 Resolving 23 y/o male- IIH Resolution ONH Drusen ONH DRUSEN SD-OCT ONH DRUSEN SD OCT Improved with EDI 23

25 Color SD-OCT Anterior Segment OCT Visante image Many units available with anterior segment capability New cap available for Cirrus 4000 and 5000 that allows Visante style imaging 24

26 Angle:Optovue Cells in A/C Plateau Iris Wound leak with choroidals Wound leak post repair 25

27 Scleral lens Scleral lens Scleral lens landing zone Two for the price of one! THE END! 26