Orbital computed tomography imaging characteristics of thyroid-associated ophthalmopathy

This study aims to investigate the distribution characteristics and correlations of orbital soft tissue volume expansion in patients with thyroid-associated ophthalmopathy (TAO) by analyzing orbital computed tomography (CT) data and to determine the most appropriate parameters and corresponding cut-off values for imaging classification. Patients with TAO who met the inclusion and exclusion criteria, along with those with lacrimal duct obstruction requiring orbital CT examination, were included in the study. Raw CT data were imported into Mimics and RadiAnt software for analysis, and measurements of orbital volume, orbital fat volume, extraocular muscle volume, optic nerve volume, and exophthalmos were obtained. The results demonstrated that the combination of Mimics and other softwares for processing orbital CT scans allows for the quantitative analysis of various soft tissue volumes within the orbit. The MV/FV ratio was found to effectively reflect the relative changes in extraocular muscle volume, serving as a valuable indicator for identifying different subtypes of TAO and providing significant clinical reference value.