Diagnosis of giant cell arteritis by head-contrast three-dimensional computed tomography angiography: two case reports.

Temporal artery biopsy is essential for the diagnosis of giant cell arteritis. It has been shown that ¹⁸F-fluorodeoxyglucose positron emission tomography-computed tomography, magnetic resonance angiography, and ultrasonography are useful for the diagnosis of giant cell arteritis. However, there are only a few reports on the usefulness of three-dimensional computed tomography angiography in the diagnosis of giant cell arteritis. We describe two cases in which giant cell arteritis was difficult to diagnose using positron emission tomography-computed tomography and magnetic resonance angiography but was diagnosed using three-dimensional computed tomography angiography, thus showing the importance of three-dimensional computed tomography angiography in the diagnosis of giant cell arteritis.

Case 1: An 81-year-old Japanese man. Laboratory investigations revealed normocytic anemia and raised inflammatory marker levels. Slight bleeding in the right posterior pole of his eyeball and leukoma of his left cornea were observed on fundus examination. Stenosis and stoppage of the temporal artery were detected on three-dimensional computed tomography angiography. A diagnosis of giant cell arteritis was made, and he was started on orally administered prednisolone. His headache and C-reactive protein levels improved. Four weeks after glucocorticoid steroid treatment, three-dimensional computed tomography angiography revealed improvement in stenosis and stoppage of temporal artery. Case 2: A 74-year-old Japanese woman. A dose of 20 mg of prednisolone was administered and her polymyalgia and polyarthritis improved; however, her headache and ear occlusion persisted. Although vasculitis was not detected on positron emission tomography-computed tomography, stenosis and stoppage of the temporal artery were detected on computed tomography angiography. She was diagnosed as having giant cell arteritis and started on orally administered prednisolone treatment (60 mg daily). Her headache and C-reactive protein levels improved. Four weeks after glucocorticoid treatment, three-dimensional computed tomography angiography showed improvement in stenosis and stoppage of temporal artery.In both patients with giant cell arteritis, three-dimensional computed tomography angiography revealed improvement in stenosis and stoppage of temporal artery after glucocorticoid treatment. We conclude that computed tomography angiography along with magnetic resonance angiography, positron emission tomography-computed tomography, and ultrasonography are important for the diagnosis of giant cell arteritis.