Macular microvasculature in patients with thyroid-associated orbitopathy: a cross-sectional study

The aim of this study was to evaluate macular blood flow in patients with thyroid-associated orbitopathy (TAO) as compared to healthy subjects. The inflammatory nature of the disease, as well as the vascular congestion caused by the increase in the volume of orbital soft tissue and extraocular muscles, rationalize the assessment of retinal blood flow changes in these patients. This is a cross-sectional study with the convenience sampling method. Macular flow density was assessed using optical coherence tomography angiography (OCTA) and compared between patients with TAO and healthy individuals. We also compared macular flow density in two subgroups of patients based on clinical activity score (CAS). Eighty-five cases, including 30 healthy individuals and 55 patients with TAO, participated. The foveal avascular zone (FAZ) area was significantly larger in the patient group than in the control. Patients with active TAO with CAS 3 or more had significantly larger FAZ areas than those with CAS less than 3 (p = 0.04). We showed that the FAZ area is larger in active TAO patients and can be considered a possible candidate feature for monitoring disease activity and thyroid-associated vasculopathy.