To view the full text, please login as a subscribed user or purchase a subscription. Click here to view the full text on ScienceDirect. Figure 1 Flowchart of patients in the study. Figure 2 Disability scores of NMOSD patients according to time of optic neuritis occurrence. ON: optic neuritis. EDSS: Expanded disabillty status scale. KVS: Kurtzke's visual function scale. WONIS: Wingerchuk optic nerve impairment scale. Highlights •Patients with NMOSD and optic neuritis have severe sustained disability.