A possible protective role of pigment proliferation against subretinal neovascularisation progression in idiopathic macular telangiectasia type II.

Idiopathic macular telangiectasia (MacTel II) is a degenerative disorder of the Müller cells, characterised by pigment proliferation and retinal degeneration. We present a case of an elderly woman with bilateral asymmetric loss of vision. Fundus examination in the right eye revealed profuse pigment proliferation at the macula and pigment plaques temporal to the macula in the left eye, with bilateral retinal greying and right-angled venules. Optical coherence tomography and optical coherence tomography angiography helped identify this condition as bilateral MacTel II with outer retinal neovascularisation and subretinal neovascularisation. Over 1 year of follow-up, progressive vision loss and neovascular changes were noted in the left eye compared with the stable vision and minimal neovascular changes in the right eye. We explore the possible role of pigment proliferation in preventing the progression of neovascularisation in eyes with MacTel II.