Postoperative ischemic complication results in neurological sequelae and longer hospitalization after unruptured middle cerebral artery (MCA) aneurysm clipping surgery. We evaluated the radiological and patient-related factors associated with ischemic complications after unruptured MCA aneurysm clipping surgery. Patient demographics, radiological findings, and intraoperative factors were compared between patients with and without postoperative ischemic complications. The clinical courses and outcomes of postoperative ischemic complications were compared according to the types of ischemic complication. Forty-two out of 2227 patients (1.9%) developed postoperative ischemic complications after MCA aneurysm clipping. Multivariate analysis revealed that diabetes mellitus (DM) was a patient-related factor. Intraarterial (IA) calcification of the distal internal carotid artery (ICA), preoperative M1 stenosis, and M1 aneurysm were radiological factors that increased the risk of postoperative ischemic complications. DM was significantly associated with divisional branch territory infarction (P = 0.04). The time to first presentation of ischemic complication was significantly longer in divisional branch territory infarction than perforator territory infarction (67.8 ± 75.9 h vs. 22 ± 20.7, P = 0.023). Twelve out of 42 patients with ischemic complications (28.6%) had unfavorable outcome (mRS > 3). Perforator territory infarction was significantly associated with an unfavorable outcome (mRS > 3, P = 0.019). IA calcification of the distal ICA, M1 stenosis and aneurysms, and DM were significantly associated with postoperative ischemic complications after unruptured MCA aneurysm clipping. Patients with DM should be closely monitored postoperatively to detect delayed occurrence of divisional branch infarction. Trial registration number: 2019-1002, Date of registration: January 1, 2005, “retrospectively registered”

未破裂大脑中动脉 (MCA) 动脉瘤夹闭手术后，术后缺血并发症会导致神经系统后遗症和更长的住院时间。我们评估了与未破裂 MCA 动脉瘤夹闭手术后缺血并发症相关的放射学和患者相关因素。比较有和没有术后缺血并发症的患者的人口统计学、放射学发现和术中因素。根据缺血并发症的类型比较术后缺血并发症的临床过程和结局。2227 名患者中有 42 名 (1.9%) 在 MCA 动脉瘤夹闭后出现术后缺血并发症。多变量分析显示糖尿病（DM）是与患者相关的因素。远端颈内动脉 (ICA) 的动脉内 (IA) 钙化、术前 M1 狭窄和 M1 动脉瘤是增加术后缺血性并发症风险的放射学因素。DM 与分区分支区域梗死显着相关（P = 0.04）。与穿支区域梗死相比，分枝区域梗死首次出现缺血并发症的时间明显长（67.8 ± 75.9 h vs. 22 ± 20.7, P = 0.023）。有缺血性并发症的 42 名患者中有 12 名 (28.6%) 有不良结果 (mRS > 3)。穿支区域梗死与不良结局显着相关（mRS > 3，P= 0.019）。未破裂 MCA 动脉瘤夹闭后，远端 ICA 的 IA 钙化、M1 狭窄和动脉瘤以及 DM 与术后缺血并发症显着相关。DM 患者术后应密切监测，以发现分区分支梗塞的延迟发生。试用注册号：2019-1002，注册日期：2005年1月1日，“追溯注册”