SUMMARY:A patient with suspected giant cell arteritis and prior negative findings on superficial temporal artery biopsy was evaluated with 320-detector row CT angiography (CTA) and whole-brain perfusion. Corticosteroid treatment was initiated on the basis of CT angiography findings of arteritis and a cortical perfusion deficit. The patient's symptoms and perfusion imaging findings resolved following therapy. Whole-brain CTA and imaging was helpful in the diagnosis and monitoring this patient with suspected vasculitis.
Large vessel cerebral vasculitis (LVCV) represents involvement of the internal carotid artery (ICA); intracranial vertebral arteries; the basilar artery; and the M1, A1, and P1 segments of the middle, anterior, and posterior cerebral arteries (MCA, ACA, and PCA, respectively).1 There is a wide range of diagnostic imaging strategies for patients with clinically suspected LVCV, including multidetector CT (MDCT), MR imaging, positron-emission tomography (PET), and Doppler sonography.2 Three-hundred-twentyϪdetector row CT enables whole-brain perfusion CT (PCT) and quantitative measurements of regional cerebral blood flow and volume (rCBF and rCBV). Such perfusion imaging potentially allows rapid reliable visualization of the effects of cerebral autoregulation mechanisms in parenchymal ischemia.Combined with CT angiography (CTA), PCT has demonstrated clinical utility in acute ischemia.3,4 The major drawback of PCT to date has been the limited volume coverage achieved with 64-section CT imaging.3 The 320 ϫ 0.5 mm detector configuration overcomes this limitation and enables assessment of the entire brain using iodinated contrast opacification for a period of time, so-called "dynamic volume CT." The specific advantage in vasculitis is that abnormalities may not follow vascular distributions, requiring whole-brain PCT to identify all findings. We report a patient who underwent dynamic volume CT before and after treatment for suspected LVCV.
Case ReportA 39-year-old right-handed man presented with a left temporal headache, which did not have specific aggregating or relieving factors. The physical examination findings were normal, with the exception of absent reflexes in the right biceps. Pertinent signs included an elevated erythrocyte sedimentation rate (ESR) of 106 mm/h, a C-reactive protein level of 8 mg/L, and a borderline white blood cell count of 11,000 cellsL/ mm 3 . The patient had normal findings on CSF analysis. The medical history was significant for left-sided headaches and a negative prior biopsy of the left superficial temporal artery (STA) for suspected giant cell arteritis (GCA). The differential diagnosis included primary headaches, vasculitis, transient ischemic attack, and impending stroke. Dynamic volume CT (AquilionONE; Toshiba, Tochigi-ken, Japan) was performed during infusion of 70-mL iodinated contrast media (ioversol, Optiray 350; Mallinckrodt, St. Louis, Mo) at 5 mL/s. Single-rotation whole-brain volume datasets were acquired (80 kV, 100 mA, 1-second rotation) intermittently in 2 st...