Microcystic macular degeneration from optic neuropathy: not inflammatory, not trans-synaptic degeneration

Sir, we read with great interest the article by Gelfand et al. (2012) in the June issue of Brain in which they describe ‘microcystic macular oedema in multiple sclerosis’. They concluded that these changes in the inner nuclear layer of the retina were best seen by spectral domain optical coherence tomography and were due to inflammatory conditions that produced a breakdown in the blood–retinal barrier. In response, Abegg et al. (2012) noted similar changes in a case of compressive optic neuropathy due to glioma and suggested retrograde trans-synaptic degeneration as an alternative explanation. Furthermore, Balk et al. (2012) also noted similar features in a case of recurrent optic neuritis not due to multiple sclerosis, adding evidence of inflammation as the key aetiology.However, we have seen several hundred patients …