Effect of direct neurological evaluation on outcomes during treatment of unruptured intracranial aneurysms under local anesthesia

Objective The greatest advantage of local anesthesia (LA) in endovascular treatment (EVT) of unruptured intracranial aneurysms (UIAs) is that direct neurologic evaluation can be performed during the procedure, unlike with general anesthesia. However, the usefulness of such direct evaluation has not been established. In this study, we attempted to assess the effects of direct neurologic evaluation by identifying the causes, management, and outcomes of clinical symptoms during the procedure and procedure-related events during EVT under LA. Methods We retrospectively evaluated the medical and radiologic data of 1000 patients (1015 UIAs) who had undergone coil embolization under LA from 2008 to 2016. Results Clinical symptoms were identified in 62 patients (6.2%) during the procedure. The symptoms improved during the procedure in 27 of these patients (44%) and after the procedure in another 28 (45%). One month after the procedure, 55 patients (89%) had good outcomes and 7 (11%) had poor outcomes. Procedure-related events occurred in 67 patients (6.7%); of these 67 events, 39 were symptomatic and 28 were asymptomatic. Thirty-five of the 39 symptomatic events (90%) [13 of 13 (100%) ruptures, 6 of 10 (60%) thrombus formations, and 16 of 16 (100%) thromboembolisms] were detected on the basis of clinical symptoms before angiographic changes were identified, and they were managed promptly. All 28 patients with asymptomatic events were managed safely without further complications before symptoms developed. Conclusions We demonstrated that appropriate management of clinical symptoms and procedure-related events under LA led to favorable outcomes of EVT of UIAs.