MR T2 relaxation time for the assessment of retrobulbar inflammation in Graves' ophthalmopathy.

The results of 39 patients with severe Graves' ophthalmopathy (GO), who were monitored by magnetic resonance imaging (MRI) and tonography before and after combined immunosuppressive treatment with cyclosporine and corticosteroids, are presented. A correlation was found between the decrease in T2 relaxation time of the superior, medial, and inferior rectus muscle (p < 0.01) and the response to the immunosuppressive treatment. Muscle thickness and intraocular pressure showed less improvement (p < 0.05). The infiltrative eye signs improved partially in correlation with the T2 relaxation time. By distinguishing inflammation of the extraorbital muscles from fibrosis, the T2 relaxation time can help to select patients that benefit from immunosuppressive treatment as well as to monitor the therapeutic effect.