Transient Augmentation of Intraoperative Motor Evoked Potentials During Middle Cerebral Artery Aneurysm Surgery

Abstract

Objective: To study the clinical significance of the augmentation of intraoperative motor evoked potentials (MEPs} during direct open surgery for middle cerebral artery (MCA} aneurysms. Methods: Between 2009 and 2017, there were 134 MCA aneurysm surgeries performed with intraoperative MEP monitoring. The frequency and the cause of the augmentation with more than a 50% increase of MEP amplitude from the baseline were studied. Furthermore, the factors associated with MEP augmentation were investigated. Results: Nine patients showed MEP augmentation, and all 9 events were observed just after application of the temporary clip to the parent artery. The ratio of the maximum amplitude to baseline was 2.6±1.1, at an average of 2.4± 1.1 min after parent artery occlusion. On the other hand, 10 patients did not show MEP augmentation after parent artery occlusion, and they were compared with the patients showing MEP augmentation. It was found that the distance of the temporary clip point from the midline was smaller in patients with MEP augm entation than in those without (p=0.033}. Conclusions: MEP augmentation was thought to be an early ischemic sign preceding a significant decrease during MCA aneurysm surgery. Transient augmentation of MEPs was more frequently observed in cases with a temporary clip applied to the more proximal part of the MCA.

Clinical Usage of Different Doses of Cis-Atracurium in Intracranial Aneurysm Surgery and Its Effect on Motor-Evoked Potentials

“…There are many factors that affect MEP, such as anesthesia drugs, pacemakers, and surgical operations, among which anesthesia drugs have the greatest impact. Cis-atracurium is a synthetic bisquaternary ammonium ester type benzyl isoquinoline compound, which is a medium-acting nondepolarizing muscle relaxant, can act through competitive binding with cholinergic receptors, has a rapid onset of action, and has a good muscle relaxation effect, and is widely used in clinical anesthesia [21][22][23]. As a result, 90 ICAS patients who underwent MEP monitoring in our hospital were chosen as research subjects and divided into three groups: S1 (2 times the 95 percent effective dose (ED95) cis-atracurium), S2 (3 times ED95 cis-atracurium), and S3 (4 times ED95 cis-atracurium), each having 30 cases [24,25].…”

Prognostic value Analysis of Intraoperative Transcranial Electrical Stimulation motor evoked Potential Monitoring in Postoperative limb Function changes of Neurosurgical Patient

“…At the same time, MEP has a relatively high sensitivity in monitoring cortex, subcortical ischemia and brain function damage. When monitoring cerebral vascular operations such as aneurysm clipping and carotid endarterectomy, the amplitude change of MEP can reflect cerebral ischemia earlier [12,13]. In neurosurgery, the use of MEP monitoring to protect limb motor function has been paid more and more attention, and has been widely used in aneurysms [14,15], gliomas [16,17], carotid endarterectomy [18,19] and other diseases.…”

Usefulness of the Multimodal Fusion Image for Visualization of Deep Sylvian Veins

“… 27 ) Furthermore, some conditions that are difficult to treat without microsurgery still exist, such as large aneurysms or cerebral aneurysms that require revascularization; however, the surgical risk of these conditions is relatively high. Therefore, supportive tools to ensure safe surgery and educational tools to supplement surgical experience, such as intraoperative neuromonitoring 28 ) and surgical simulation using virtual reality technology are greatly needed. 29 ) Based on the findings of this study, multimodal fusion imaging may also help experienced neurosurgeons make informed decisions regarding the choice of treatment (clipping or coiling) or surgical approach.…”