Unilateral Retinal Pigment Epithelium Dysgenesis: Long-Term Natural Evolution and Multimodal Imaging

To present the natural course and describe the characteristic findings of a case of unilateral retinal pigment epithelium dysgenesis (URPED) and highlight the optical coherence tomography angiography characteristics of this rare fundus pattern.

Case report.

A 52-year-old male was referred 8 years ago to our clinic due to a distinctive unilateral lesion in his left fundus, of which he was aware from early adulthood. Clinical evaluation revealed an irregularly shaped patch of retinal pigment epithelium atrophy surrounding his left optic nerve, with a characteristic scalloped border and with severe distortion of the overlying retinal and vascular tissue. Retinal pigment epithelial hyperplasia was noted in the margin as well as in distinct lacunae clustered around the periphery of the lesion. Right fundus examination was normal. The patient was diagnosed with URPED and was followed annually with multimodal imaging ever since. No choroidal neovascularization or other complication was noted. However, the lesion appeared to slowly but steadily grow to eventually affect the foveal region causing severe visual loss. Best corrected visual acuity was 20/40 at baseline and 20/200 at last follow-up 8 years after the original diagnosis.

URPED is a rare retinal disease with unique clinical characteristics that can progress relentlessly even in the absence of secondary complications.