Choroidal Caverns: A Novel Optical Coherence Tomography Finding in Geographic Atrophy

PURPOSE: To describe and interpret “choroidal caverns,” an unreported optical coherence tomography (OCT) finding in the choroid of patients with geographic atrophy (GA) secondary to atrophic AMD. METHODS: Retrospective analysis of patients with GA. Main outcomes measures included estimation of the prevalence of choroidal caverns, their localization and relation with retinal-choroidal structures by reviewing medical records and multimodal imaging. RESULTS: One hundred twenty consecutive patients (mean age 80.5 ± 8.61 years) were included. Among the 201 eyes with GA, 17 eyes of 15 patients presented choroidal caverns on OCT B-scan in GA areas (a total of 43 choroidal caverns, mean 2.5/eye, variably localized in the Sattler and Haller layers, with relative preservation of the choriocapillaris). This accounts for 12.5% estimated prevalence (6.5–18.5, 95% confidence interval [CI]) of choroidal caverns in GA areas of atrophic AMD patients. Choroidal caverns appeared on OCT (both B-scan and en face) as gaping hyporeflective cavities in the choroid, typically empty, angular, without hyperreflective borders, often with punctate/linear hyperreflectivities internally. Indocyanine angiography and OCT-Angiography confirmed that the areas occupied by these cavities do not represent perfused choroidal blood vessels. CONCLUSIONS: Choroidal caverns represent a relatively infrequent peculiar finding in GA areas of atrophic AMD eyes. They appear as gaping angular hyporeflective cavities in areas devoid of choroidal vessels, often with punctate/linear hyperreflectivities internally. Choroidal caverns may possibly arise from nonperfused ghost vessels and persistence of stromal pillars where the vessels were originally situated.