Filigree Vascular Pattern in Combined Hamartoma of Retina and Retinal Pigment Epithelium on OCT Angiography

Purpose: To evaluate the vascular structure within combined hamartoma of retina and retinal pigment epithelium (CHRRPE) lesions using OCT angiography (OCTA). Design: Multicenter, retrospective, observational analysis, Participants: Twenty eyes of patients diagnosed with CHRRPE. Methods: Retrospective analysis of color fundus photographs, OCT, and OCTA of 20 eyes with CHRRPE. Morphologic characteristics of CHRRPE and the OCT features were correlated with the density of the filigree vascular pattern and with the published histopathologic findings of CHRRPE lesions. Main Outcome Measure: Density of flow signals, that is, the filigree vascular pattern seen on OCTA in the deep capillary plexus, graded as high (>20), intermediate (10-20), or low (<10). Results: Of 20 lesions, 11 were peripapillary, 8 were macular, and 1 was equatorial in location. A high density of filigree vascular pattern was observed in most peripapillary CHRRPE lesions, which also showed full-thickness retinal involvement (8/10). A low density of filigree pattern was seen in macular lesions, which showed partial-thickness retinal involvement and preretinal fibrosis (5/6). Conclusions: A filigree vascular pattern on OCTA is seen in CHRRPE lesions. High density of this pattern is noted in CHRRPE lesions with a peripapillary location, full-thickness retinal disorganization, and minimal preretinal fibrosis. These findings correlate well with published histopathologic findings of CHRRPE lesions both in terms of topographic and morphologic features. OCT angiography provides a promising method for further study of these lesions. (C) 2019 by the American Academy of Ophthalmology