Evaluation of choroidal thickness and choroidal vascular blood flow in patients with thyroid-associated orbitopathy (TAO) using SD-OCT and Angio-OCT.

Abstract

The aim of this study was to evaluate changes in choroidal thickness and in choroidal vascular blood flow in patients with thyroid-associated orbitopathy (TAO) and their relationship with clinical features and disease activity using spectral domain optical coherence tomography (SD-OCT) and Angio-OCT technology. Eighteen patients and control subjects underwent a complete eye examination, OCT, and Angio-OCT. We also obtained angiographic scans at 3 different consecutive levels (L1, L2, and L3) below the choriocapillary. The subfoveal choroid was significantly thicker in TAO patients than the control eyes (285.6275 ± 32.5μm compared with 135.89 ± 19.8μm, respectively, p= 0.0089). The correlation analysis in the TAO group showed a significant correlation between the choroidal thickness and EUGOGO clinical score (r= 0.84, p= 8.44032E-07). Vascular flow of choriocapillary was markedly reduced in subjects with TAO compared with healthy subjects (49.78 ± 4.5 vs. 53.36 ± 1.07; p= 2.5105E-07) and vascular flow of the deeper layer L3 resulted higher in subjects with TAO than in healthy subjects (46.9 ± 20.23 and 41.475 ± 3.06; p= 0.01168). Subfoveal choroidal thickness and choroidal blood flow were significantly different in patients with TAO compared with healthy subjects.