Abstract
Introduction: Optical coherence tomography angiography (OCTA) is an emerging technique to investigate retinal and choroidal microvascular alterations in patients with systemic sclerosis (SSc). This systematic review and meta-analysis aimed to evaluate the features of retinal and choroidal microvasculature using OCTA among SSc patients. Methods: The methodology of the study was based on PRISMA guidelines. PubMed, Scopus, Web of Science, and Embase were searched systematically on November 25, 2023, for relevant studies utilizing OCTA as the main diagnostic tool to assess the retinal and choroidal microvasculature in SSc patients versus healthy controls. Random-effect or fixed model meta-analysis was used based on the heterogeneity of studies. Results: Eleven observational comparative studies, including 366 patients with SSc and 350 healthy controls, conducted between 2020 and 2023, were included in this review. Meta-analysis findings revealed a significant decrease in vessel densities in both the superficial and deep capillary plexuses (SCP and DCP) among SSc patients compared to controls. However, there were no significant differences observed in the foveal avascular zone (FAZ) area and choriocapillary flow area (CCFA) between SSc patients and controls. Moreover, central macular thickness (CMT) consistently exhibited a decrease in SSc patients, while retinal nerve fiber layer (RNFL) thickness showed no significant differences. Although radial peripapillary capillary (RPC) vessel density, subfoveal choroidal thickness (CMT), and cup/disc ratio yielded mixed results, with some studies indicating significant changes in the SSc group, meta-analysis could not be performed due to variations in the OCTA machines used across the included studies. Conclusion: This systematic review demonstrates retinal and choroidal microvascular abnormalities in SSc using OCTA. Longitudinal studies are needed to understand how these abnormalities evolve over time in patients with SSc and whether these abnormalities correlate with the clinical features of SSc.