[Intraoperative microvascular Doppler ultrasonography monitoring in intracranial aneurysm surgery]

To evaluate the reliability of intraoperative microvascular Doppler ultrasonography (MDU) in cerebral aneurysm surgery.MDU was conducted among 46 patients with 51 cerebral aneurysms undergoing 47 operations to examine the blood flow velocity in the aneurysmal sac and in the adjacent vessels before and after aneurysm clipping.MDU verified 6 cases of stenosis or occlusion of an adjacent vessel induced by clip positioning that had escaped detection by visual inspection (12.76%, 6/47). In addition, MDU demonstrated that one out of the 51 aneurysms failed to be occluded (1.96%). The incidence of stenosis, occlusion of adjacent vessel, and aneurysm failing to be occluded was closely correlated with the size of aneurysm, and such conditions were prone to occur in anterior communicating artery (ACoA) and internal carotid artery (ICA) aneurysms.MDU should be used routinely in cerebral aneurysm surgery, especially in cases of giant aneurysms and aneurysms without obvious neck. In cases of ACoA and ICA aneurysms, MDU is more useful.