Amaurosis Fugax Dolorosa: A Prodromal Syndrome in Optic Neuritis Associated With Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease.

Objectives: Amaurosis fugax (AF) is typically vascular but can rarely be associated with optic neuritis (ON). We describe AF preceding myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) ON.

Methods: We retrospectively reviewed our MOGAD cohort (July 2024-April 2024). Inclusion criteria were (1) AF-defined as transient visual loss <24 hours without retinal ischemic lesions-before first ON and (2) fulfilled international MOGAD 2023 diagnostic criteria. Demographics, symptoms/signs, MRI, and optical coherence tomography (OCT) data were collected. Descriptive statistics summarized the findings.

Results: In total, 8 of 350 (2.3%) MOGAD patients with ON experienced AF. Most patients (7/8, 87.5%) were women, and all reported periocular pain. Transient visual episodes were typically brief (median, 15 minutes; range, 1-300 minutes) and usually less than 1 hour (6/8, 75.0%). Amaurosis fugax affected the right (n = 4), left (n = 3), or both (n = 1) eyes. Within 1 week, 7 developed ON. MRI showed optic nerve enhancement in involved eye in 8 of 8 (100%). OCT completed in 1 patient at the time of AF showed increased peripapillary retinal nerve fiber layer thickness. No alternative diagnoses emerged during follow-up.

Discussion: Painful AF is a previously unrecognized and specific prodrome of MOGAD-associated ON; identifying this rare presentation may enable earlier diagnosis and treatment.