The utility of computed tomography and magnetic resonance imaging in the diagnosis and surgical planning of thyroid eye disease and dysthyroid optic neuropathy.

Thyroid eye disease (TED) is an autoimmune inflammatory orbitopathy that can threaten vision in severe cases due to dysthyroid optic neuropathy (DON). While TED is primarily diagnosed clinically, orbital imaging with computed tomography (CT) and magnetic resonance imaging (MRI) plays a pivotal role in confirming the diagnosis in atypical presentations, distinguishing TED from other orbital diseases, assessing disease activity, and guiding management. This narrative review examines the role of CT and MRI in the diagnosis and management of TED, with particular focus on their application in differential diagnosis, identification of DON, and surgical planning including volumetric analysis. We summarize characteristic CT and MRI findings in TED, such as enlargement of extraocular muscles with tendon sparing and inflammatory changes detectable on MRI and compare utility of each modality. Imaging features that predict or confirm DON, a complication that affects roughly 5%-8% of patients with TED, are highlighted, including apical muscle crowding and optic nerve compression. We also discuss how modern imaging techniques facilitate surgical planning for orbital decompression and enable objective monitoring of disease progression or response to therapy. This review underscores how CT and MRI contribute to comprehensive TED care and identifies emerging advancements and gaps in knowledge that future research should address.