Comprehensive visualization of choroidal microvessels and nerve structure in graves’ disease without clinical ophthalmopathy using ultra-widefield OCT angiography

PURPOSE: Choroidal characteristics and nerve structure were evaluated in Graves' disease patients without ocular signs using Ultra-Widefield OCT angiography and compared with healthy controls, and their correlation with TSI was assessed. METHODS: Twenty-four patients with Graves' disease (GD) without ocular signs and twenty-three healthy controls were retrospectively included. Choroidal thickness (CT), radial peripapillary capillaries (RPCs) area, choroidal vascular volume (CVV), choroidal stromal volume (CSV), and choroidal vascular index (CVI) were measured using ultra-widefield OCT angiography. Thyroid hormone levels were collected in GD patients, including free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH), thyroid-stimulating immunoglobulin (TSI), and anti-TSH receptor antibody (A-TSHR). RESULTS: Central foveal and parafoveal-superior choroidal thickness were reduced in Graves' disease group (P < 0.05). For CSV in the GD group, significant differences were observed in the central fovea, parafoveal-temporal, parafoveal-inferior, perifoveal-temporal, perifoveal-inferior regions (all P < 0.05), with the greatest reduction in the fovea (P = 0.004). CVV differed only in the parafoveal-nasal region. Correlation analysis after bonferroni correction showed positive associations between CSV and TSI in the parafoveal-superior, parafoveal-nasal, and perifoveal-superior regions (Adjusted P < 0.05), and a inverse correlation between CVI and TSI in the fovea region (Adjusted P = 0.05). CONCLUSIONS: Patients with Graves' disease without ocular signs show altered choroidal characteristics (CT, CSV, CVV) compared with healthy controls, among which CSV and CVI may be related to thyroid hormone levels, especially TSI.