Abstract
Purpose :
Multiple evanescent white dot syndrome (MEWDS) is an acute, multifocal, usually unilateral retinopathy affecting young adults. In this study we investigated the role of RPE in the pathogenesis of MEWDS by multimodal imaging.
Methods :
A retrospective case series of 5 patients diagnosed with acute MEWDS has been analyzed. Each patient was studied with multimodal imaging techniques including fundus autofluorescence (Blue FAF, 488 μm), fluorescein angiography (FA), indocyanine green angiography (ICGA), enhanced depth imaging spectral-domain optical coherence tomography (EDI-OCT, HRA Spectralis, Heidelberg Engineering, Heidelberg, Germany) and optical coherence tomography angiography (OCTA HRA Spectralis, Heidelberg Engineering, Heidelberg, Germany or XR Avanti Optovue, Freemont, California).
Results :
All the lesions of patients showed typical clinical features, with areas of hyperautofluorescence on FAF corresponding to the white dots. FA findings included early and late hyperfluorescence suggesting a normal choriocapillary and a decreased masking effect of RPE.
On ICGA round hypocyanescent lesions were visible in the early and late phase consistent with a possible masking effect.
On OCT the lesions corresponded to an ellipsoid zone – outer nuclear layer disruption, and in two patients some of the lesions showed an increase in signal transmission with an overlying apparently intact RPE band, possibly due to a displacement of melanine granules in RPE cells. None of the patients’ images showed any alteration of the choroid or retinal vascular plexuses on OCT-A.
Conclusions :
The RPE findings on OCT, OCT-A, FAF, FA and ICGA stand out as indicators of cell swelling and intracellular organules and melanosomes rearrangement, witnessing a pivotal role of this retinal layer in the clinical course of the disease.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.