Sixty-Four-Section CT Cerebral Perfusion Evaluation in Patients with Carotid Artery Stenosis before and after Stenting with a Cerebral Protection Device

Abstract

Brain tissue viability depends on cerebral blood flow (CBF) that has to be kept within a narrow range to avoid the risk of developing ischemia. The aim of the study was to evaluate by 64-section CT (VCT) the cerebral perfusion modifications in patients with severe carotid stenosis before and after undergoing carotid artery stent placement (CAS) with a cerebral protection system. Fifteen patients with unilateral internal carotid stenosis (>or=70%) underwent brain perfusional VCT (PVCT) 5 days before and 1 week after the stent-placement procedure. CBF and mean transit time (MTT) values were measured. Decreased CBF and increased MTT values were observed in the cerebral areas supplied by the stenotic artery as compared with the areas supplied by the contralateral patent artery (P < .001). A significant normalization of the perfusion parameters was observed after the stent-placement procedure (mean pretreatment MTT value, 5.3 +/- 0.2; mean posttreatment MTT value, 4.3 +/- 0.18, P < .001; mean pretreatment CBF value, 41.2 mL/s +/- 2.1; mean posttreatment CBF value, 47.9 mL/s +/- 2.9, P < .001). PVCT is a useful technique for the assessment of the hemodynamic modifications in patients with severe carotid stenosis. The quantitative evaluation of cerebral perfusion makes it a reliable tool for the follow-up of patients who undergo CAS.