Multiple Evanescent White Dot Syndrome: Findings from a Large Northern California Cohort.

Purpose: To report the clinical and imaging characteristics of multiple evanescent white dot syndrome (MEWDS) from a large single-center cohort.

Design: Single-center, retrospective cohort study.

Participants: A total of 111 patients previously diagnosed with MEWDS in the Kaiser Permanente Northern California system from 2012 to 2019.

Methods: Two retina specialists reviewed the medical records and all available retinal imaging, including Humphrey visual field testing, fundus photography (FP), OCT, fluorescein angiogram (FA), and fundus autofluorescence (FAF). Patients were excluded from analysis if confirmatory imaging was unavailable.

Main Outcome Measures: Patient characteristics, visual acuity, clinical examination and imaging findings, and final diagnosis.

Results: Seventy-three patients (65.8%) were confirmed to have the diagnosis of MEWDS. Fifty-eight (79.5%) were female, with a mean (standard deviation [SD]) age at presentation of 35.2 (14.2) years, and mean refractive error of -1.6 diopters. Initial mean (SD) visual acuity was logarithm of the minimum angle of resolution (logMAR) 0.39 (0.31) and improved to mean (SD) logMAR 0.07 (0.15) at final follow-up. Presenting symptoms included blurred vision (82%), scotomas (56%), photopsias (43%), and floaters (23%). Nine patients (12%) had a previously diagnosed autoimmune condition, and 2 patients (3%) had documentation of a recent vaccination. Antecedent upper respiratory infection was documented in 15 of 66 patients (23%). Noted clinical and imaging features include ellipsoid zone disruption (100%), white fundus lesions (92%), FA hyperfluorescence (92%), foveal granularity (74%), vitreous cell (53%), and optic disc edema (52%). Twenty-nine of the 111 patients (26%) were initially misdiagnosed with MEWDS and subsequently given an alternative diagnosis, including other white dot syndromes, syphilis, primary vitreoretinal lymphoma, myopic degeneration, and central serous chorioretinopathy.

Conclusions: Multiple evanescent white dot syndrome is a rare self-limiting condition of the outer retina. Although a distinct set of clinical exam and imaging findings permit recognition of this disease, misdiagnosis is not uncommon.