Choroidal thickness in patients with thyroid-associated ophthalmopathy, as determined by swept-source optical coherence tomography.

Aim: This study used swept-source optical coherence tomography (SS-OCT) to investigate subfoveal choroidal thickness (SFCT) in patients with thyroid-associated ophthalmopathy (TAO) who displayed different levels of disease activity and severity.

Methods: Thirty patients with TAO (60 eyes) and 38 healthy controls (67 eyes) in Shanghai, China, were recruited for this study. Disease activity and severity were graded using European Group on Graves' Orbitopathy standardised criteria. SFCT values were determined by SS-OCT.

Results: In total, 129 eyes were included in the final analysis. The mean SFCT was significantly thicker among patients with active disease (276.23±84.01 µm) than among patients with inactive disease (224.68±111.61 µm; p=0.049) or healthy controls (223.56±78.69 µm; p=0.01). There were no differences in SFCT among patients with moderate-to-severe disease, patients with severe disease and healthy controls (p>0.05). Changes in SFCT demonstrated strong predictive ability to distinguish active TAO from inactive TAO (area under the curve=0.659, 95% CI 0.496 to 0.822).

Conclusions: SFCT was strongly associated with Clinical Activity Score in patients with TAO. Choroidal thickening was observed during active TAO. SS-OCT offers a non-invasive method for follow-up assessment.