Evaluation of Optical Coherence Tomography Angiography Parameters in Pulmonary, Ocular and Extrapulmonary Sarcoidosis

To evaluate retinal and choroidal microvascular alterations in sarcoidosis using optical coherence tomography angiography (OCTA) and assess their association with different clinical phenotypes and disease duration.

This cross-sectional study included 76 patients with sarcoidosis divided into three subgroups: pulmonary (n = 33), pulmonary + ocular (n = 25), and pulmonary + extrapulmonary involvement (n = 18), along with 31 healthy controls. OCTA was used to quantify vessel density (VD) in the superficial (SCP) and deep capillary plexus (DCP), foveal avascular zone (FAZ) area, choriocapillaris flow, and radial peripapillary capillary (RPC) network. Statistical analyses included ANOVA, Tukey post hoc, and correlation tests.

No significant differences were observed between groups for SCP-VD, RPC-VD, FAZ area, or choriocapillaris flow. However, DCP-VD showed significant intergroup differences, particularly in foveal and perifoveal regions (p = 0.005 and p = 0.012). Post hoc analyses revealed that DCP-VD was significantly lower in sarcoidosis subgroups than in controls, even among patients without clinical ocular involvement. No significant correlation was found between disease duration and OCTA metrics, though weak negative trends were observed for perifoveal DCP-VD and foveal SCP-VD.

DCP-VD is selectively reduced in sarcoidosis, suggesting early subclinical microvascular compromise, particularly in extrapulmonary and ocular phenotypes. OCTA may serve as a valuable non-invasive tool for detecting subtle retinal microvascular changes before clinical signs appear. Further longitudinal studies are warranted to assess the prognostic implications of these findings.