1990 Volume 30 Issue 6 Pages 417-421
A 69-year-old female with bilateral giant internal carotid aneurysms at the cavernous portion was admitted with complaints of diplopia and radiating pain. The aneurysm on the left side was larger and symptomatic, and treated with the internal carotid artery ligation and the superficial temporal arterymiddle cerebral artery (STA-MCA) double bypasses. However, intraoperative somatosensory evoked potential (SEP) monitoring revealed the disappearance of N20 100 minutes after the carotid occlusion and rapid recovery of N20 following flow restoration. Therefore, a high-flow bypass using radial artery grafting was installed, and carotid ligation was performed again without any change in SEP. Postoperative angiograms demonstrated complete disappearance of the aneurysm and sufficient blood supply through a patent high-flow bypass. Although both STA-MCA double bypasses were occluded, no change in cerebral blood flow was detected by single photon emission computed tomography. Her neurological deficits improved, and she is being followed as an outpatient with a plan of second surgery for the remaining aneurysm.
