Evaluation of choroidal vascularity index in systemic sclerosis patients

Abstract

Objective: To investigate the comparison of choroidal vascularity index (CVI) between patients with systemic sclerosis and healthy individuals.

Methods: This study was designed prospective non-randomized cross-sectional study. Eighty-six eyes (43 patients) with limited cutaneous systemic sclerosis (lcSSc), 60 eyes (30 patients) with diffuse cutaneous systemic sclerosis (dcSSc) and 60 eyes (30 subjects) of age-and sex-matched healthy individuals were recruited. Subfoveal choroidal thickness, CVI and modified Rodnan skin score (mRSS) were evaluated. Enhanced depth imaging- optical coherence tomography scans were binarized using Niblack's autolocal threshold and CVI was determined as the luminal choroidal area/total choroidal area ratio.

Results: The mean CCT values were 268.00±68.59 µm, 286.90±70.88 µm, 321.73±94.13 µm in lcSSc group, dcSSc group and control group, respectively. The mean CVI was 61.84±2.84% in lcSSc group, 54.62±5.84% in dcSSc group and 62.41±4.13% in control group (p=0.001). The mean CVI of the SSc patients was 58.91±5.58 and there was significant difference between control group (p<0.001). The mean mRSS was 3.84±2.50 in lcSSc group and 14.07±6.81 in dcSSc group (p<0.001). There was a statistically significant negative correlation between mRSS and CVI (r=-0.448, p<0.001) CONCLUSION: Choroidal vascularity index provides valuable information to monitor the disease progression and lower CVI values seem to be related to the disease severity in patients with systemic sclerosis.

Keywords: Choroidal thickness; Choroidal vascularity index; Image binarization; Optical coherence tomography; Systemic sclerosis.