Subclinical retinal atrophy in the unaffected fellow eyes of multiple sclerosis and neuromyelitis optica.

We compared the retinal thickness in the unaffected eyes among the following subtypes of unilateral optic neuritis (ON): multiple sclerosis (MS-ON), neuromyelitis optica spectrum disorder with anti-AQP4 autoantibody (AQP4-ON), patients with serum anti-MOG antibody (MOG-ON), and idiopathic ON. In the chronic phase, macular GCC and circum-papillary RNFL in the unaffected eyes were both atrophied in MS-ON and AQP4-ON, but were not atrophied in the others. Titers of anti-AQP4-Ab was suggested to be associated with such latent neurodegenerative process in AQP4-ON. Long-term follow up of OCT is recommended even in the unaffected side in MS-ON and AQP4-ON.