Motor evoked potentials monitoring in resection of infratentorial lesions

Abstract

Resection of infratentorial tumors is one of the most complicated surgical interventions in neurosurgery. These operations require high-quality technical equipment and high skill of the surgeon. The greatest challenge is the manipulation in the limited area with a high density of functional structures and anatomy changed by a tumor. As a result, the risk of new neurological deficits is high and can lead to a disability of the patient. The use of intraoperative neurophysiological monitoring allows a significant risk reduction of surgery. This technique allows the neurosurgeon to identify all functionally important structures in the area of surgical intervention and provides control of their functions intraoperatively in real time. Transcranial motor evoked potentials are the modality of intraoperative monitoring, a record of the motor evoked potentials in response to transcranial electrical stimulation. The method assesses the integrity of corticospinal and corticobulbar pathways, since these are the main motor pathways of the central nervous system, their damage may lead to a significant motor deficit.This article presents a review and an analysis of the literature within the historical context, which shows the development of motor evoked potentials in neurosurgery, especially in infratentorial surgery. The methodology of the transcranial motor evoked potentials and corticobulbar evoked potentials and evaluation criteria during surgery for infratentorial lesions are described. Moreover, we compared the literature data with our own experience.