Tapunya K.Aurboonyawat T.Mahidol University2026-05-092026-05-092026-05-01Siriraj Medical Journal Vol.78 No.5 (2026) , 350-358https://repository.li.mahidol.ac.th/handle/123456789/116614Objective: This study aimed to determine the effectiveness of IOCA in reducing residual AVMs after surgery. Materials and Methods: We retrospectively reviewed all AVM resection surgeries performed at Siriraj Hospital between January 2008 and December 2022. The use of intraoperative cerebral angiography was recorded. The primary outcome was the presence of residual AVM on postoperative imaging. Results: The study included 92 patients, who were divided into two groups: those undergoing IOCA (44) and those undergoing surgery without IOCA (48). The initial incidence of residual AVMs prior to IOCA did not differ between the two groups (15.90% vs. 18.75%, p=0.720). However, postoperative imaging revealed significantly fewer missed residual AVMs in the IOCA group compared to the non-IOCA group (4.54% vs. 18.75%, p=0.036; absolute risk reduction (ARR) = 14.21% and a number needed to treat (NNT) = 7.04). The overall rate of acute complications did not differ significantly between the two groups (p = 0.108), but the mean length of hospital stay was higher in the non-IOCA group (19.31 vs. 8.57, p=0.001). Conclusion: Intraoperative cerebral angiography may help reduce the incidence of residual AVMs after surgery and decrease the length of hospital stays.MedicineArticleSCOPUS10.33192/smj.v78i5.2774272-s2.0-10503760225722288082