Case #34 – OCT RNFL Discordance with GDx, GCC and VFs

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References 1. Digre, Kathleen B., and James J. Corbertt. "Branch Retinal Artery Occlusion with Cilioretinal Vessel Supplying the Retina." The Watercooler. Web. <>. 2. Leung, Christopher K.S., Shi Lam, Robert N. Weinreb, Shu Liu, Cong Ye, Lan Liu, Jing He, Gilda W.H Lai, Taipin Li, and Dennis S.C Lam. (in press) "Retinal Nerve

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Special Acknowledgement Dan Epshtein Acknowledgements Sanjeev Nath Brad Fortune Sherry Bass Samantha Slotnick Piero Barboni Donald Hood

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Jerome Sherman, OD, FAAO Jerome Sherman, O.D., is perhaps optometry's most prolific writer, publishing over 650 clinical articles, research manuscripts, book chapters and two CDs. He is senior author Of three books that were published in 2007, and has delivered over three thousand lectures both nationally and internationally. He has served as

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Comments and Conclusions (Con't d) • Review of the images of the circumpapillary RNFL using all three OCT systems tested did not reveal any segmentation errors and hence the false negative findings are not easily explainable. • One explanation is that circumpapillary OCT RNFL thickness measurements include blood vessels (which artificially increase the RNFL measurement)

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Comments and Conclusions • GDx appears to demonstrate circumpapillary RNFL abnormalities many months prior to circumpapillary RNFL thinning with OCT in this case and perhaps in many others. • In a monkey model, it has been demonstrated that such RNFL changes do occur earlier with GDx than with SD OCT and this discordance has

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GDx, iVue GCC, and maia Comparison Structure Function concordance is undeniable as demonstrated here with GDx and GCC for structure and maia microperimetry for function. These 3 findings belie the "normal" circumpapillary OCT results. Although the GDx is a circumpapillary measurement and both maia fields and the GCC are centered around the fovea,

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iVue iWellnessExam OU The vertical scan of the OD (above left) demonstrates the attenuated inner retina inferiorly. The Inner Retinal Thickness Table demonstrates a 47 µ difference in the thickness of the superior vs inferior retina in the OD and only a 2.5 µ difference in the OS. There is also more than

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iVue iWellnessExam OD Using the iHealthCheck program, a single 2 second scan yields 8 high resolution cross sections as well as the Inner Retina Thickness (or GCC) Map. Note that the Full Retina Thickness Map is 7mm x 7mm.

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RTVue Inner vs Outer Retinal Thickness Accurate segmentation of the inner and outer retinal layers is supported by the devastating impact to the inner retina, which suffered an arterial occlusion, and the relative sparing of the outer retina, which receives its vascular supply primarily from the choroid.

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