Task: Question Answering
Input (English): Context: The purpose of this study was to investigate the relation between preoperative chronic cerebral ischemia and postoperative new cerebral ischemia in patients undergoing carotid endarterectomy (CEA).', 'We reviewed the diffusion weighted magnetic resonance images (DWI) of the 51 patients (37 men, mean age 68.8\u2009±\u20098.4 years) undergoing isolated CEA in the preoperative and early postoperative period. The number, anatomic location and the size of new ischemic lesions were recorded.', 'In the preoperative period, 28 (54.9 %) patients were symptomatic. There was chronic cerebral infarction in the preoperative DWI images of 17 patients (33.3 %). In the postoperative period, there was newly developed cerebral ischemia in postoperative DWI images of eight (15.7 %) patients. Six of the eight patients with newly developed cerebral ischemia had chronic cerebral infarction in their preoperative DWI images. The incidence of newly developed cerebral ischemia after CEA in patients with preoperative chronic cerebral ischemia was significantly higher than the incidence in patients without preoperative chronic cerebral ischemia (p\u2009=\u20090.01).\Question: Is previous chronic cerebral infarction predictive for new cerebral ischemia after carotid endarterectomy?
Output (English): The results of the present study suggest that preoperative chronic cerebral ischemia may aggravate postoperative newly developed cerebral ischemia in patients undergoing CEA.