Yannuzzi, Lawrence A.

Purpose: To describe two cases of retinal detachment with hydration folds and discuss the possible cause of these outer retinal abnormalities. Methods: The medical and imaging records of two patients with retinal detachment and hydration folds were examined. Patients: A 43-year-old myopic woman who developed a retinal detachment secondary to a macular hole and a 35-year-old man referred with a rhegmatogenous retinal detachment masquerading as an exudative detachment were each found to have retinal hydration folds. Results: On near-infrared reflectance imaging, the hydration folds appeared similar to eddy currents, and these corresponded to curvilinear outer retinal plications on optical coherence tomography. The photoreceptor outer segments appeared thickened and elongated, and there was apparent lateral expansion of the outer retinal layers. Conclusion: Hydration folds are found in rhegmatogenous retinal detachment and demonstrate reproducible imaging characteristics on near-infrared imaging and optical coherence tomography. The cause for such outer retinal plications is currently unknown. We suspect that they form as a result of hydration of the glycosaminoglycans in the interphotoreceptor matrix, which lies between the photoreceptors. Additional studies are warranted to explore this pathophysiology.

Purpose: To describe atypical cases of multiple evanescent white dot syndrome (MEWDS) associated with foveal exudation, increased choroidal thickness, and secondary Type 2 (subretinal) neovascularization. Methods: Four cases of atypical MEWDS were studied at a retina referral center. Patients underwent evaluation with multimodal retinal imaging, including fluorescein angiography, indocyanine green angiography, spectral-domain and enhanced depth imaging optical coherence tomography (OCT). Two patients were imaged with OCT angiography. Results: Four patients (3 female, 1 male) with a median age of 23.5 years presented with acute onset, painless, decreased central vision. All cases demonstrated fundus findings consistent with MEWDS on color photography, indocyanine green angiography, fluorescein angiography, fundus autofluorescence, and structural OCT imaging. On structural OCT, all 4 patients were noted to have hyperreflective subretinal material and increased subfoveal choroidal thickness ranging from 307 μm to 515 μm. Type 2 neovascularization was diagnosed in all four patients using fluorescein angiography, indocyanine green angiography, and/or OCT angiography. Two patients had poor visual acuity at the last follow-up despite resolution of characteristic clinical findings of MEWDS. Conclusion: A subset of patients with atypical MEWDS may develop persistent poor vision due to subfoveal exudation and secondary Type 2 neovascularization. Patients showing increased choroidal thickness at presentation may be more susceptible to this unusual presentation.