**3.1 Cerebral ischemia**

The incidence of postoperative cerebral ischemia has been reported to be approximately 3.5% in adult patients and 16.9% in pediatric patients [32, 58]. Sakamoto et al. studied the risk factors for perioperative complications in revascularization surgery and found that the severity of the disease, history of TIA, and indirect bypass procedures were the major determinants for postoperative neurological deficits [59]. Similarly, Zhao et al. recently found that advanced Suzuki stage and preoperative ischemic presentation were independent risk factors for postoperative ischemia [60]. Lastly, The Carotid Occlusion Surgery Study (COSS) investigators found that the mechanism of stroke was usually attributed to hypoperfusion and the occurrence of artery-to-artery emboli or thrombosis [61].
