Background We aimed to analyze outcomes of clipping and coiling in treating unruptured intracranial aneurysms (UIAs) in elderly patients and to identify the age at which perioperative risk increases based on national cohort data in South Korea. Methods The incidence of perioperative intracranial hemorrhage (ICRH), perioperative cerebral infarction (CI), mortality, and moderate to severe disability data of the patients who underwent coiling or clipping for UIAs were retrieved. Estimated breakpoint (EBP) was calculated to identify the age at which the risk of treatment increases. Results A total of 38,207 patients were treated for UIAs. Among these, 22,093 (57.8%) patients underwent coiling and 16,114 (42.2%) patients underwent clipping. The incidence of ICRH, requiring a secondary operation, within 3 months in patients ≥ 65 years that underwent coiling and clipping was 1.13% and 4.81%, respectively, and that of both groups assessed were significantly higher in patients ≥ 75 years (coiling, P = 0.013, relative risk (RR) 1.81; clipping, P = 0.015) than younger patients. The incidence of CI within 3 months in patients aged ≥ 65 was 13.90% and 9.19% in the coiling and clipping groups, respectively. The incidence of CI after coiling in patients aged ≥ 75 years ( P < 0.001, RR 1.96) and after clipping in patients aged ≥ 70 years ( P < 0.001, RR 1.76) was significantly higher than that in younger patients. The mortality rates within 1 year in patients with perioperative ICRH or CI were 2.41% and 3.39% for coiling and clipping groups, respectively, in patients ≥ 65. These rates increased significantly at age 70 in the coiling group and at age 75 for the clipping group ( P = 0.012 and P < 0.001, respectively). Conclusion The risk of treatment increases with age, and this risk increases dramatically in patients aged ≥ 70 years. Therefore, the treatment decisions in patients aged ≥ 70 years should be made with utmost care.

Study Design A Retrospective Cohort Study. Objective To introduce a new Doppler sonography-assisted pedicle screw fixation technique that enables vertebral artery (VA) monitoring during surgery and compares the accuracies of Doppler sonography-assisted cervical pedicle screw fixation and the conventional technique. Methods This retrospective study was performed on 164 consecutive patients that underwent pedicle-based screw fixation from C2 to C6 between January 2013 and August 2020. Surgery was performed without intraoperative Doppler sonography in 84 cases (the Control group) or with intraoperative Doppler sonography in 80 cases (the Doppler group). Proper positioning of pedicle screws was graded, and the incidences of VA injury and screw breach in the Control and Doppler groups were compared. Results Three hundred and ninety-nine screws were placed in the 164 patients (Doppler, 186 screws; Control, 213 screws). The percentages of well-positioned screws in the two groups were significantly different (Doppler, 97.8%; Control, 85.0%). There were two cases of VA injury in the Control group, an incidence of 2.4%, but no case in the Doppler group. Conclusion Doppler sonography can be used intraoperatively to help guide the trajectory of the cervical pedicle screw insertion. It can detect the VA inside the screw trajectory and may reduce the risk of VA injury during cervical pedicle screw fixation.