We report a case of a 42-year-old woman with unilateral exophthalmos. Additionally we found impaired motility of the affected bulbus, ptosis and reduction of visual acuity. Orbital MR imaging demonstrated dense fibrotic masses filling the whole orbita including the extraocular muscles as well as the optic nerve. Tissue specimens were extracted while performing orbital decompression via a lateral orbitotomy. Histological examination revealed a lymphatic infiltration and fibrotically destroyed tissue containing the lacrimal gland. After surgical decompression, oral steroid therapy and immunotherapy, a recovery of the visual loss could be seen.
Vision (V) evaluates the visual repercussion particularly due to the development of dysthyroid optic neuropathy. This is assessed through visual acuity, pupillary reflexes, color vision, visual fields, optic nerve examination, and visual evoked potentials. Most of these tests should be performed in all patients, as optic neuropathy frequently occurs in patients with little or no proptosis. CT scans may be necessary in selected cases to confirm the presence of an orbital apex syndrome or before surgical decompression (Figure 1 ).