This patient presented with classic findings of macular telangiectasia type 2 (MacTel2), including an opaque perifoveal retina, inner retinal crystal, and black clumps of intraretinal pigment migration.
Deep retinal angiographic leakage is noted in the right eye with more diffuse staining in the left eye. OCT scanning shows an outer retinal cavitation OD and type 2 macular neovascularization (MNV) OS.
Learning Points:
Originally described by Gass (Arch Ophthalmology 1982;100:769-780), MacTel2 is a neurodegenerative disorder, most likely originating from Müller cell dysfunction.
The term telangiectasia is misleading because the funduscopic findings are mostly nonvascular.
The refractile inner retinal ‘crystals’ are thought to be Müller cell footplates. The foveal retina shows a whitish discoloration, most likely due to retinal opacification resulting from Müller cell dysfunction.
Photoreceptor loss allows RPE cells to migrate along intraretinal capillaries, causing the coarse clinical pigment clumping.
The majority of patients will also have subclinical chorioretinal anastomosis associated with right-angle venules (Spaide et al., Retina 2018;38:1920-1929).
Secondary MNV can be successfully treated per age-related macular degeneration protocols.
