Significance: Large-vessel giant cell arteritis (GCA) can be a diagnostic dilemma for the eye care provider because it may not involve the typical cranial arteries. When any of its potential ocular complications are diagnosed, it is important to consider this unusual form of GCA. Purpose: To report an unusual ophthalmic presentation of large-vessel GCA with sequential bilateral anterior ischemic optic neuropathy and branch retinal artery occlusion.

Methods: A 65-year-old previously healthy woman experienced sequential bilateral anterior ischemic optic neuropathy with branch retinal artery occlusion in the absence of other signs and symptoms suggestive of cranial GCA.

Results: Extensive workup, including temporal artery biopsy, failed to demonstrate vascular inflammation suggestive of GCA or vascular abnormalities, such as atheromatous plaques, but coincidentally revealed a breast tumor, which was excised. Positron emission tomography scan was performed revealing distinct hypermetabolism of the thoracic and abdominal aorta consistent with large-vessel GCA, and corticosteroid therapy was initiated.

Conclusions: Large-vessel GCA is an underdiagnosed and undertreated type of GCA that does not typically affect the cranial arteries but rather larger proximal aortic branches. When associated with ocular complications, it can be a puzzling diagnostic dilemma for the eye care provider.