Prediction of cerebral hyperperfusion after carotid endarterectomy using cerebral blood volume measured by perfusion-weighted MR imaging compared with single-photon emission CT.

BACKGROUND AND PURPOSE Cerebral hyperperfusion syndrome is a rare but serious complication of carotid revascularization, including carotid endarterectomy (CEA) and carotid stent placement, which can occur in patients with preoperative impairments in cerebral hemodynamics. The purpose of this study was to determine whether preoperative cerebral blood volume (CBV) measured by perfusion-weighted MR imaging (PWI) could identify patients at risk for cerebral hyperperfusion after CEA. MATERIALS AND METHODS CBV was measured by using PWI before CEA in 70 patients with unilateral internal carotid artery (ICA) stenosis (>or=70%) and without contralateral ICA steno-occlusive disease. Cerebral blood flow (CBF) was also measured by using single-photon emission CT before and immediately after CEA and on the 3rd postoperative day. RESULTS A significant correlation was observed between preoperative CBV and increases in CBF immediately after CEA (r = 0.785, P < .0001). Whereas hyperperfusion immediately after CEA (CBF increase of >or=100% compared with preoperative values) was observed in 7 of 15 patients (47%) with elevated preoperative CBV, no patients with normal preoperative CBV exhibited post-CEA hyperperfusion. Furthermore, elevated preoperative CBV was the only significant independent predictor of post-CEA hyperperfusion. Finally, hyperperfusion syndrome developed on the 5th postoperative day in 2 of the 7 patients who displayed hyperperfusion immediately after CEA. CONCLUSION Measurements of preoperative CBV by PWI might help to identify patients at risk for cerebral hyperperfusion after CEA in the absence of contralateral ICA steno-occlusive disease.