**5.2 Computed tomography (CT) or magnetic resonance imaging (MRI)**

CT and/or MRI of the orbits is indicated if there is any uncertainty about the cause of ophthalmopathy, particularly in a patient with unilateral exophthalmos, to rule out a retrobulbar tumor or arteriovenous malformation. Approaches used in assessing the activity of ophthalmopathy are very helpful in determining which individuals will be benefitted from immunosuppressive treatment. Measurement of the relaxation time for extraocular muscles on T2-weighted MRI, Clinical activity scores (CAS), and orbital scanning with indium In 111 pentetreotide [54] have all been suggested for this purpose but have not been fully assessed. These above tests are not needed for the majority of individuals, who have only mild or moderate Graves' ophthalmopathy [72].
