Multimodal Imaging Characteristics of Sarcoid Retinal Granulomas

To describe the clinical presentation and multimodal imaging characteristics of retinal granulomas in patients with ocular sarcoidosis.

In this retrospective observational case series, patients with definite or presumed ocular sarcoidosis presenting with retinal granulomas were evaluated. Multimodal retinal imaging was reviewed to characterize lesion morphology, imaging patterns, and longitudinal evolution.

Retinal granulomas were identified in three patients with ocular sarcoidosis from diverse racial backgrounds. On fundus photographs, lesions ranged from multiple, superficial, small, faint yellow-gray nodules to more distinct, deeper yellow lesions, predominantly located in the mid- to peripheral retina. All retinal granulomas demonstrated hyperreflectivity on OCT with four distinct morphologic patterns: (1) inner and/or outer retinal granulomas; (2) retinal granulomas associated with retinal pigment epithelium (RPE) disruption and hypertransmission defects; (3) sub-RPE granulomas located between the RPE and Bruch's membrane; and (4) combined chorioretinal granulomas extending from the choroid. FAF demonstrated predominantly isoautofluorescent lesions in the absence of RPE involvement, whereas hypoautofluorescence was observed when the RPE was involved. FA was available for one patient and demonstrated late hyperfluorescent staining of the retinal granulomas. Longitudinal imaging demonstrated evolution from active inflammatory nodules to regression with residual retinal and/or RPE changes, commonly manifesting as punched-out atrophic lesions.

Retinal granulomas may represent an underrecognized manifestation of ocular sarcoidosis. In our series, multimodal imaging allowed detailed characterization of their morphologic patterns and longitudinal evolution. Recognition of these characteristic imaging features of sarcoid retinal granulomas may facilitate consideration of sarcoidosis in the differential diagnosis of retinal infiltrative lesions.