GIANT CELL ARTERITIS OF THE BASAL CEREBRAL ARTERIES: CORRELATION OF MRI, DSA, AND HISTOPATHOLOGY

Abstract

Histopathologic data on basal cerebral artery alterations in large vessel vasculitis of the brain are scarce. However, several recent reports suggest that these alterations may be noninvasively visualized by MRI. Specifically, high-resolution, fat and blood signal suppressed (black-blood) T1-weighted imaging has demonstrated contrast enhancement in the wall of affected arteries.1,2 In the presented case, we were able to correlate these MRI findings with conventional angiography and histopathology. ### Case report. A 59-year-old otherwise healthy woman without apparent vascular risk factors initially presented with moderate right-sided hemiparesis. Diffusion-weighted MRI revealed small acute left frontal brain infarction. Digital subtraction angiography (DSA) demonstrated high-grade stenosis of the terminal segment of the left internal carotid artery (ICA) and the proximal portions of the left middle (MCA) and anterior cerebral artery (ACA) (figure, A). High-resolution black-blood T1-weigthed MRI demonstrated marked contrast enhancement in the terminal segment of the left ICA and the left posterior communicating artery (PCoA) (figure, B and C). Repeated CSF examinations showed mild pleocytosis with 7 to 19 cells/mm3 (mainly lymphocytes and monocytes) and a normal protein content and glucose CSF/serum ratio. Erythrocyte sedimentation rate (ESR), leukocyte count, and C-reactive protein were normal in repeated testings. Serology was negative for HIV, viral hepatitis, chlamydia, Treponema pallidum , and Mycoplasma pneumoniae infection. CSF testing was negative for varicella zoster virus, Epstein-Barr virus, cytomegalovirus, Borrelia burgdorferi , and mycotic disease. Extensive laboratory testing (ANA differentiation, ANCA, C3, C4, cryoglobulins, …