NEUROSURGICAL VASCULAR COMPLICATIONS ASSOCIATED WITH ANEURYSM CLIPS EVALUATED BY POSTMORTEM ANGIOGRAPHY

Neurosurgical vascular complications were evaluated by postmortem angiography in a consecutive prospective series of 63 patients in Helsinki who suffered a fatal outcome following neurosurgery for ruptured intracranial aneurysm. Operative vascular complications were revealed in 28 (44%) of the cases. Massive intraoperative bleeding resulting from rupture of the aneurysm or adjacent major artery during dissection or clip application complicated the operation in 16 (25%) patients. Clip-induced obstruction of cerebral arteries was detected by angiography in seven cases (11%). In six of the patients an adjacent cerebral vessel was accidentally clipped. In one case a kinking of the clip had caused obstruction of the right anterior cerebellar artery with resulting frontal infarct. A combination of rupture of the internal carotid artery and accidental ligation of the left posterior cerebellar artery occurring simultaneously during the clipping of a ruptured basilar aneurysm was detected in one patient (2%). Other types of complication were revealed in four cases (6%): detachment of clip with re-bleeding; clipping of an uninvolved aneurysm instead of the ruptured one; displacement of the clip beneath the ruptured aneurysm. Operations on ruptured basilar artery aneurysm were significantly (P < 0.01) more prone to complications. The results indicate that operative vascular complications play a significant role in the mortality of aneurysm patients. Post-mortem angiographic technique with contrast medium that vulcanizes at room temperature is particularly suitable for demonstration of the haemodynamic significance of clip-induced cerebrovascular accidental occlusions, and is the only method at autopsy to reveal an occlusion caused by a kinking of a properly placed aneurysm clip.