Object: Whether routine intraoperative angiography is necessary for cerebral aneurysm surgery is currently under debate. In this study the authors prospectively assessed the cerebrovascular surgeon's accuracy in predicting the need for intraoperative angiography.
Methods: Between January 2002 and January 2003, 200 consecutive patients (141 female and 59 male patients, mean age 52.8 years) with 235 aneurysms underwent routine intraoperative angiography. Before the operation, the surgeons indicated whether they believed that intraoperative angiography was necessary. Their responses were recorded as "intraoperative angiography necessary" or "intraoperative angiography unnecessary." Regardless of the response, all patients underwent intraoperative angiography after the aneurysm had been clipped. Changes in treatment resulting from intraoperative angiography were compared with surgeons' preoperative predictions of the need for intraoperative angiography. Intraoperative angiography was predicted to be necessary in 41 cases (20%) and unnecessary in 159 cases (80%). Its use altered treatment in 14 patients. Seven of these patients were among the group in which intraoperative angiography was deemed necessary and seven were in the group in which it was considered unnecessary. In the latter group, two patients had residual aneurysms, three had parent vessel occlusion, and two had previously undiagnosed aneurysms. Only one patient (0.5%) sustained a major intraoperative complication attributed to angiography.
Conclusions: Given the frequency of significant disease that remains undetected if intraoperative angiography is used on a selective basis and the low complication rate associated with the procedure, the use of intraoperative angiography should be considered in the majority of aneurysm cases.