Effects of indocyanine green videoangiography and electrophysiological monitoring on surgery for intracranial aneurysms

We analyzed the outcome of 62 consecutive patients with unruptured intracranial aneurysm treated by surgical clipping. Thirty-one cases were operated without intraoperative monitoring, 17 cases with indocyanine green videoangiography (ICGA), and 14 cases with electrophysiological monitoring (EPM) in addition to ICGA. Complete obliteration of the aneurysm was confirmed in all 62 cases. Diffusion-weighted imaging of MRI disclosed no ischemic lesions after surgery in any of the cases. Asymptomatic venous infarction was detected by CT study in 2 cases. Cranial nerve palsy occurred in 4 cases but EPM could not detect it. There was no difference among the group without monitoring, the group with ICGA and the group with ICGA and EPM. The mortality and morbidity of all cases was calculated as 0% and 6.5%, respectively. ICGA appeared to be useful in surgery for aneurysms encasing perforators or for repair of problems such as premature rupture. eicosapentaenoic acid (EPA) seemed effective in surgery for anterior choroidal artery aneurysms or aneurysms requiring trapping before clipping. However, monitoring would not have been effective without extensive dissection of aneurysms, suggesting that basic microsurgical techniques are crucial for successful surgery. (author)