Microvascular alterations in the diagnosis of systemic sclerosis: a new approach

Abstract The study investigated the conjunctival and fundus retinal vascular density changes in individuals with systemic sclerosis (SSc) by optical coherence tomography angiography (OCTA) to clarify the relationship between these changes and clinical features of SSc. Twelve SSc patients and twelve healthy controls (HCs) participated (24 eyes each). OCTA photographs each eye's conjunctiva and macular retina. Images were segmented using annular partitioning, Early Treatment Diabetic Retinopathy Study partitioning (ETDRS), and hemispheric quadrants. Superficial and deep retina layers of fundus microvascular (MIR), macrovessel (MAR), total MIR (TMI), and temporal conjunctival vessel densities were assessed and compared across groups. OCTA results showed no significant difference in conjunctival blood vessel density between groups (P > 0.05). MIR and TMIR densities differed significantly (P < 0.05). Using a new segmentation method, we found that the SR, IL, S, L, C1 and C2 regions in both the superficial and deep layers, the R and C3 regions in the superficial layer, and the S, L and C4 regions in the deep layer of the retina were lower than that in the patient group (P < 0.05). Deep MAR and conjunctival vascular densities correlated positively (r = 0.5206; P < 0.05). OCTA results show lower microvascular density in active SSc patients' superficial and deep retinal layers. A potential indicator for the diagnosis of SSc may be the vascular density measurement obtained by OCTA.