Abstract TP169: Perioperative Assessment of Cerebral Perfusion Territories using Arterial Spin Labeling Magnetic Resonance Imaging in Patients with Carotid stenosis
[Background] Territorial arterial spin labeling (TASL) MRI offers a unique opportunity to visualize non-invasively cerebral perfusion territory (PT) by selective labeling of the feeding arteries without contrast medium. The objective of this study was to evaluate the PT status in patients with carotid stenosis and effect of carotid endarterectomy (CEA) on PT.
[Materials and Methods] This study included 22 patients with carotid stenosis (20 men and 2 women; mean age 73 years) treated by CEA. All of them underwent TASL preoperatively and on the day after surgery. Ipsilateral internal carotid artery (ICA) blood flow (ICF) was measured by electromagnetic flowmeter just before and after endarterectomy during the surgery. Perfused volume (PV) of each feeding artery was calculated from perfused area and thickness of slices. Cerebral blood flow (CBF) was calculated as ICF/PV.
[Results] Before CEA, the PV of ipsilateral ICA were significantly smaller than those of contralateral ICA. After CEA, the ipsilateral PV significantly increased and the asymmetry of PV of ICA was corrected (Fig.1 & 2). ICF also increased (82 to 178 ml/min). Accordingly, ipsilateral CBF defined by ICF/PV significantly increased (28 to 50 ml/100cm3/min). In a patient with postoperative hyperperfusion (HP), however, ICF remarkably increased from 10 to 200 ml/min while the PV increased only slightly (111 to 127 cm3, Fig.2).
[Conclusion] TASL could evaluate the peri-operative change of cerebral PT non-invasively. CEA corrected the asymmetry of PT measured by TASL in patients with carotid stenosis. In a patient with HP after CEA, however, the increase of PT was small, which may suggest pathophysiological basis for HP.
- Magnetic resonance imaging
- Carotid arteries
- Perfusion imaging
- Regional circulation
- Cerebrovascular circulation
- © 2012 by American Heart Association, Inc.