title: Surgical management of aneurysms of the bifurcation of the internal carotid artery.
abstract: Internal carotid artery (ICA) bifurcation aneurysms are rare and easily bleed in younger patients, but are difficult to treat surgically, due to perforators surrounding and adherent to the aneurysm. A series of 25 patients treated by clipping under the operating microscope are analyzed and compared with previous cases. Twenty-five patients, 11 men and 14 women (mean age 51 years), were treated by the same neurosurgeon. Seventeen patients presented with subarachnoid hemorrhage (Hunt & Kosnik Grade I in three, II in five, III in two, IV in seven), five with unruptured ICA bifurcation aneurysms, and three with unruptured ICA bifurcation aneurysms but another ruptured aneurysm. There were 23 small, one large, and one giant ICA bifurcation aneurysms. The projection was superior in 12, anterior in seven, and posterior in six cases. Pterional approach was employed for all cases. Outcomes were evaluated at discharge with the Glasgow Outcome Scale. Favorable outcomes (good recovery (GR) and moderate disability (MD)) were obtained in ten of 17 patients with ruptured ICA bifurcation aneurysm. Favorable outcomes were significantly greater in Grades I and II (three in I, four in II) than in Grades III and IV (one in III, two in IV; P=0.0498). Seven of eight patients with unruptured ICA bifurcation aneurysm had favorable outcomes. Temporary clipping and projection of the aneurysm did not affect the outcome. Causative factors of unfavorable outcomes were primary brain damage in cases of small and large aneurysms and perforator damage in the case of giant aneurysm. Poor clinical grade and vasospasm are the causative factors of poor outcome in patients with ruptured ICA bifurcation aneurysm. Preservation of perforators is crucial in cases of giant aneurysm. Clipping of unruptured ICA bifurcation aneurysms is recommended since they tend to bleed at a lower age than other aneurysms.
authors.affiliation: Department of Neurosurgery, Yamanashi Medical University, 1110 Shimokato, Tamaho-cho, Nakakoma-gun, Yamanashi 409-3898, Japan.
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Miyazawa
authors.forename: Hideaki
authors.initials: H
authors.lastname: Nukui
authors.forename: Toru
authors.initials: T
authors.lastname: Horikoshi
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Yagishita
authors.forename: Masao
authors.initials: M
authors.lastname: Sugita
authors.forename: Kazuya
authors.initials: K
authors.lastname: Kanemaru
mesh_terms: D001921:Brain / Q000473:pathology; D002340:Carotid Artery Diseases / Q000473:pathology / Q000601:surgery*; D002343:Carotid Artery, Internal / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D002532:Intracranial Aneurysm / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D013525:Surgical Instruments; D016896:Treatment Outcome; D020301:Vasospasm, Intracranial / Q000150:complications