Congenital simple hamartoma of the retinal pigment epithelium: 4 cases with multimodal imaging

Background Congenital simple hamartoma of the retinal pigment epithelium is often identified as an incidental finding. One important issue is the differentiation of these benign lesions from other lesions which could be potentially sight-threatening.Methods This study describes 4 cases of congenital simple hamartoma of the retinal pigment epithelium that were referred to a university-based hospital. Multimodal imaging including fundus photo, multicolor fundus photo, fundus autofluorescence, optical coherence tomography (OCT), OCT angiography, fluorescein angiography and multifocal electroretinogram is provided.Results The first case is a young man with an incidental finding of this lesion. The second and third cases are diabetic patients with congenital simple hamartoma of the retinal pigment epithelium and diabetic macular edema and the fourth one is a case of congenital simple hamartoma of the retinal pigment epithelium with a full-thickness macular hole.Conclusions Differentiation of congenital simple hamartoma of the retinal pigment epithelium from other potentially sight-threatening lesions is important. Multimodal imaging can be helpful regarding this issue. Besides typical findings described in the literature, unique features in our cases include concurrent diabetic macular edema and association with a full-thickness macular hole.