Apical optic nerve compression of dysthyroid optic neuropathy on computed tomography.

Computed assisted tomography (CT) of seven cases of dysthyroid optic neuropathy showed moderate to severe thickening of the extraocular muscles at the orbital apex, white CT of two control cases of dysthyroid orbitopathy without neuropathy showed minimal or fusiform thickening. The consequences include probable apical compression with optic nerve neuropathy either by direct pressure on the nerve or its blood supply. The management of these cases is either by oral administration of corticosteroids in high dosage with gradual tapering or radiation therapy to the orbital apex (approximately 3,000 rad over a ten-day period). If surgical decompression is to be attempted, it should be designed to decompress the optic nerve at the orbital apex.