OUTER RETINA CAPILLARY INVASION AND ELLIPSOID ZONE LOSS IN MACULAR TELANGIECTASIA TYPE 2 IMAGED BY OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY

Purpose: Macular telangiectasia Type 2 (MacTel2) is a neurodegenerative and vascular disease limited to the macular area, resulting ultimately in Muller cell and photoreceptor loss and intra or subretinal proliferation. Optical coherence tomography angiography was used to correlate the proliferation of capillaries in the outer retina with the topography of the ellipsoid zone (EZ) loss. Methods: Thirty eyes of 15 patients with MacTel2 were examined using optical coherence tomography angiography. Images of the superficial and deep capillary plexus were analyzed and compared with en-face angio-flow images of the outer retina and en-face image of the EZ. Results: Twenty-one eyes were available for the study, including 12 with invasion of the outer retina capillary on optical coherence tomography angiography but without subretinal neovascularization. The outer retina capillary proliferation had a radial pattern in eight cases, formed loops in four, and was circumscribed to an area of EZ loss on en-face images. In nine cases, there was no outer capillary proliferation including two cases with foci of EZ loss. Conclusion: Optical coherence tomography angiography shows capillary proliferation in the outer retina corresponding to areas of EZ loss, which could be a useful marker to monitor the efficacy of possible treatments in MacTel2 disease.