title: The significance of intraoperative monitoring of muscle motor evoked potentials during unruptured large and giant cerebral aneurysm surgery.
abstract: The goal of this study was to characterize the utility of muscle motor evoked potentials (MMEPs) elicited by direct cortical stimulation as a means of monitoring during unruptured large and giant cerebral aneurysm surgery. This analysis focused on intraoperative changes in MMEPs and their relationship to postoperative motor function. The study population consisted of 50 patients who underwent surgery for large (n = 31) or giant (n = 19) cerebral aneurysms. Intraoperative MMEPs were continuously and successfully obtained in muscles belonging to the vascular territory of interest. There was no postoperative motor paresis in 31 (62%) patients in whom intraoperative MMEPs remained unchanged. Transient MMEP change occurred in 15 (30%) of the 50 patients, but 9 of those patients had no postoperative motor deficits, 5 had transient motor deficits, and 1 suffered permanent motor deficits resulting from postoperative delayed blood flow insufficiency due to arteriosclerosis of the parent artery. Permanent MMEP loss occurred in 4 (8%) of 50 patients, all of whom developed severe and permanent postoperative motor deficits. MMEP is a useful monitoring modality in patients undergoing surgery for large or giant cerebral aneurysms. This strategy can help predict functional prognosis or guide the neurosurgeon intraoperatively in an effort to promote better outcomes.
authors.affiliation: Department of Neurosurgery, Asahikawa Red Cross Hospital.
authors.forename: Seiji
authors.initials: S
authors.lastname: Takebayashi
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Kamiyama
authors.forename: Katsumi
authors.initials: K
authors.lastname: Takizawa
authors.forename: Tohru
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Norihiro
authors.initials: N
authors.lastname: Saitoh
mesh_terms: D019054:Evoked Potentials, Motor / Q000502:physiology*; D006801:Humans; D002532:Intracranial Aneurysm / Q000503:physiopathology / Q000601:surgery*; D007431:Intraoperative Complications / Q000175:diagnosis / Q000503:physiopathology; D016343:Monitoring, Intraoperative; D010291:Paresis / Q000175:diagnosis* / Q000503:physiopathology; D011183:Postoperative Complications / Q000175:diagnosis / Q000503:physiopathology; D011379:Prognosis