Internuclear ophthalmoplegia in giant cell arteritis.

Ophthalmoplegia from ischemia to peripheral ocular motor nerves or muscles may complicate the course of giant cell arteritis (GCA). Although brainstem ischemia is known to occur in GCA, internuclear ophthalmoplegia has not been described. Two cases of biopsy-proven GCA are described in which internuclear ophthalmoplegia resulted from brainstem ischemia. Embolization from thrombosed extradural segments of inflammed vertebral arteries, or arteritis of brainstem perforating vessels may account for brainstem infarction. Rapid tapering of steroids was temporally related to brainstem infarction in both cases.