This healthy 43YO male was referred for asymptomatic retinal findings. Vision was 20/40 OD and 20/30 OS.
Color imaging of the right eye shows a foveal cyst with pericentral opaque whitened retina and numerous inner retinal crystals. A right-angle venule is noted superotemporally.
OCT scanning shows inner foveal cavitations with variable loss of the outer retinal bands. Temporal foveal outer retinal atrophy is also noted. The left macula shows an encircling, pericentral, opaque retina with mild crystals. OCT reveals milder inner cavitations with an outer foveal microdefect.
Learning Points:
Originally described by Gass (Arch Ophthalmology 1982;100:769-780), macular telangiectasia type 2 (MacTel2) is a neurodegenerative disorder, most likely originating from Muller cell dysfunction. The term telangiectasia is misleading, as the funduscopic findings are mostly non-vascular. The refractile inner retinal ‘crystals’ are thought to be Muller cell footplates. The foveal retina has a whitish discoloration, most likely due to retinal opacification from dysfunctional Muller cells. Photoreceptor loss allows RPE cells to migrate along intraretinal capillaries, causing the coarse clinical pigment clumping (not seen in our patient).
Most patients will also have subclinical chorioretinal anastomosis in association with right-angle venules (Spaide et al, Retina 2018;38:1920-1929). Secondary macular neovascularization can be successfully treated per age-related macular degeneration protocols.
