Multiple evanescent white dot syndrome Rim Kahloun Sonia Attia Samah Mbarek Riadh Messaoud Department of ophthalmology Fattouma Bourguiba University Hospital Faculty of Medicine,University of Monastir Monastir, Tunisia

History 24-year-old woman Medical and ocular history: unremarkable Blurred vision and scotoma in the left eye (OS) since a few days

No anterior chamber cells or flare No Vitreous cells or flare First Presentation Visual acuity: 20/20 OD, 20/32 OS No anterior chamber cells or flare No Vitreous cells or flare Intraocular pressure: 12 mmHg OU

Fundus examination shows normal findings OD and multiple deep yellow-white dots with foveal granularity OS.

Visual field testing Visual field testing shows enlargement of the blind spot OS.

Fluorescein angiography early hyperfluorescence and late staining of the white dots

Indocyanine green angiography Late-phase multiple hypofluorescent lesions with peripapillary area of hypofluorescence.

Optical coherence tomography disruption of the outer retinal layers

Electroretinography (ERG) Scotopic ERG: decrease in a-wave amplitudes and latences and a decrease in b-wave amplitude with normal latences. Photopic ERG: decrease in b-wave amplitude with normal latences OS

Multiple evanescent white dot syndrome (MEWDS) Final diagnosis Multiple evanescent white dot syndrome (MEWDS)

Management No specific treatment Observation

Follow-up Resolution of retinal white dots Regression of macular granularity, leaving subtle retinal pigment epithelial changes Visual acuity recovery within 8 weeks.

Conclusion MEWDS is a rare disorder of the choroid and RPE that should be considered in differential diagnosis of acute unilateral visual loss in young, healthy patients The diagnosis of MEWDS can usually be made on the basis of typical clinical features. A multimodal diagnostic approach including FA, ICGA, SD-OCT, fundus autofluorescence, visual field testing, and ERG may help establish the definitive diagnosis and differentiate MEWDS from other entities that present with white dots. The visual prognosis of MEWDS is often excellent.