UNILATERAL RETINAL PIGMENT EPITHELIUM DYSGENESIS: NEW CASES, LITERATURE REVIEW, AND CONSIDERATIONS OF THE...

To report new cases of unilateral retinal pigment epithelium dysgenesis (URPED), review the literature, and compare its characteristics with other conditions, including combined hamartoma of the retina and retinal pigment epithelium.

Case reports and analysis of multimodal imaging findings, and complications of URPED.

Three new male patients of typical URPED, aged 40 to 75 years, were described. With these new cases, in addition to those previously published, 26 cases in total were reported, highlighting the value of clinical and imaging tools. Clinically, URPED was detected at a mean age of 31 years, mainly in men (15/26, 57%), as a flat pigmented lesion (19/26, 73%), sometimes with a honeycomb pattern of the entire lesion (4/26, 15%), but systematically with spiculated or fringe-like margins (26/26, 100%). The tumor was systematically located at the posterior pole, generally contiguous with the optic disk (23/26, 88%). Fundus autofluorescence and fluorescein angiography systematically showed a characteristic inversion (black/white) of URPED at the spiculated margins. Indocyanine green angiography, electrophysiology, B-scan ultrasonography, and functional tests seemed to be of lesser diagnostic value. Optical coherence tomography showed a normal overlying retina, although retinal thinning with photoreceptor disruption and/or internal limiting membrane irregularities were sometimes observed. Other conditions, including combined hamartoma of the retina and retinal pigment epithelium, retinal hemangioblastoma, RPE adenoma/adenocarcinoma, and ocular trauma sequelae may present with a similar small area of spiculated border, usually associated with retinal thickening and folding, and a dense epiretinal membrane.

Unilateral retinal pigment epithelium dysgenesis has typical clinical and imaging features allowing differentiating it from other ocular conditions.