Giant cell arteritis mimicking idiopathic orbital inflammatory disease.

PURPOSE To report an unusual presentation of giant cell arteritis, referred from primary care, mimicking orbital apex syndrome. CASE REPORT A 72 year old woman was referred with a two week history of pyrexia, dull right eye ache, 2mm of right proptosis, mild conjunctival chemosis and restriction of right eye movements. RESULTS An erythrocyte sedimentation rate (ESR) was 90 and fluorescein angiography showed almost complete choroidal non-perfusion suggestive of giant cell arteritis. Temporal artery biopsy confirmed the diagnosis. CONCLUSIONS Giant cell arteritis (GCA) typically presents with anterior ischemic optic neuropathy (AION), choroidal ischemia, central retinal artery occlusion, infrequently manifesting as an ocular motility problem, but has rarely been known to mimick idiopathic orbital inflammatory disease. Prompt recognition and therapy can minimize the chance of ipsilateral ocular involvement and protect the fellow eye.