LAUSR

OBJECTIVE This study aims to examine the risk factors that can cause intraoperative rupture (IOR), and especially, the role of surgical experience. To our knowledge, this is the first study to analyze the effect of the surgeon's experience on the IOR rate in two different perspectives. METHODS 1000 aneurysms in 775 patients were operated by a single-neurosurgeon. The clinical and radiological data, and intraoperative video recordings of all patients were retrospectively analyzed. To evaluate the role of the surgeon's experience on the IOR rate, the aneurysms were divided chronologically into both five-year periods and each 100 aneurysms. Number, stage, severity, location, management of IORs and patients' outcomes were determined. RESULTS IOR occurred in 55 aneurysms (5.5% per aneurysm). The incidence of IOR decreased gradually in the first two groups of 5-year periods (11.4%, 5.9%, respectively). However, in the last three groups, the decline remained stable (4-5%). Considering all groups, this decrease was statistically significant (p=0.037). When this evaluation was made for each group of 100 aneurysms, almost same results were obtained. The mortality rate also gradually decreased over the years (p=0.035). Of 8 possible risk factors, rupture status was found to be the only independent predictor for IOR (OR= 8.68, 95%CI= 3.69-20.47, p <0.001). CONCLUSIONS Increased surgical experience reduces the IOR rate from 10-11% to 4-5% after an average of 250 aneurysm operations. However, this rate does not decrease further with more experience. To our knowledge, a learning curve regarding IOR is presented for the first time in the literature.