Comprehensive Visualization of Choroidal Alterations in Thyroid Eye Disease With Ultra-Widefield OCT Angiography

To evaluate choroidal and optic disc alterations in eyes with thyroid eye disease (TED) compared with healthy eyes by using TowardPi widefield optical coherence tomography angiography (OCTA). This was a retrospective cross-sectional cohort study. A total of 112 participants (60 TED patients and 52 healthy controls) underwent TowardPi widefield OCTA, which provided detailed demographic and clinical data. Three-dimensional choroidal data, including thickness, vascular metrics, and optic disc measurements, were obtained from the built-in software. The study included 24 eyes with dysthyroid optic neuropathy (DON), 24 eyes with active non-DON TED, 71 eyes with inactive TED, and 104 healthy eyes. Choroidal thickness significantly decreased in the optic disc region during the DON phase (148.71 ± 78.98 µm) compared to normal eyes (182.35 ± 51.98 µm) and inactive TED eyes (191.34 ± 58.86 µm) (P = 0.030). In DON, choroidal stromal volume was reduced (34,183.81 ± 10,649.01 × 106 µm3) compared to normal (46,339.53 ± 16,711.99 × 106 µm3) (P = 0.002), whereas the choroidal vascular index increased (42.67% ± 3.41%) compared to normal (38.53% ± 6.35%) (P = 0.002). Optic disc area increased in DON (1.99 ± 1.24 mm2) compared to inactive TED (1.39 ± 0.38 mm2) (P < 0.001), along with reduced retinal nerve fiber layer blood-flow density in DON (45.09% ± 3.07%,) compared to normal (47.84% ± 1.41%) (P < 0.001). This study highlights the critical role of choroidal and optic disc alterations in TED pathophysiology and underscore the utility of widefield OCTA in identifying these changes, particularly in DON-risk patients.