Identification of motor pathways during tumor surgery facilitated by multichannel electromyographic recording.

OBJECT The goal of this study was to determine the usefulness of electromyographic (EMG) recording in locating motor pathways near the central sulcus or internal capsule during surgery. METHODS Multichannel EMG recordings were compared with visual observation of contralateral body movement that was elicited by direct cortical or subcortical stimulation used to identify motor pathways before and during tumor resection. The EMG recordings were more sensitive than visual observation alone in identifying motor responses: in 30% of cases, responses were identified by EMG recording alone at some point during the operation and, in 9% of cases, EMG responses were the only responses observed. Additionally, EMG recordings often detected seizure activity resulting from electrical stimulation of the cortex that could not be appreciated on visual inspection. No new motor deficits were seen postoperatively in 88% of the patients in this series. CONCLUSIONS Using EMG recording in addition to motor pathway mapping results in greater sensitivity, allowing the use of lower stimulation levels and facilitating detection of stimulation-induced seizure activity.

[1]  G. Schaltenbrand,et al.  Atlas for Stereotaxy of the Human Brain , 1977 .

[2]  M. Berger,et al.  Functional mapping-guided resection of low-grade gliomas. , 1995, Clinical neurosurgery.

[3]  M. Mikhael,et al.  Effect of the extent of surgical resection on survival and quality of life in patients with supratentorial glioblastomas and anaplastic astrocytomas. , 1987, Neurosurgery.

[4]  M. Mikhael,et al.  Supratentorial gliomas: surgical considerations and immediate postoperative results. Gross total resection versus partial resection. , 1987, Neurosurgery.

[5]  S. Ronner,et al.  Cortical mapping for defining the limits of tumor resection. , 1987, Neurosurgery.

[6]  G A Ojemann,et al.  Individual variability in cortical localization of language. , 1979, Journal of neurosurgery.

[7]  M. Berger,et al.  The effect of extent of resection on recurrence in patients with low grade cerebral hemisphere gliomas , 1994, Cancer.

[8]  G A Ojemann,et al.  Functional cortex and subcortical white matter located within gliomas. , 1996, Neurosurgery.

[9]  C. Woolsey,et al.  Localization in somatic sensory and motor areas of human cerebral cortex as determined by direct recording of evoked potentials and electrical stimulation. , 1979, Journal of neurosurgery.

[10]  S. Goldring,et al.  Localization of function in the excision of lesions from the sensorimotor region. , 1984, Journal of neurosurgery.

[11]  M. Berger,et al.  Rapid termination of intraoperative stimulation-evoked seizures with application of cold Ringer's lactate to the cortex. Technical note. , 1998, Journal of neurosurgery.

[12]  E. Clarke,et al.  The human brain and spinal cord : a historical study illustrated by writings from antiquity to the twentieth century , 1968 .

[13]  P H Crandall,et al.  The magnetic and electric fields agree with intracranial localizations of somatosensory cortex , 1988, Neurology.

[14]  M. Berger,et al.  Minimalism through intraoperative functional mapping. , 1996, Clinical neurosurgery.

[15]  G A Ojemann,et al.  Brain mapping techniques to maximize resection, safety, and seizure control in children with brain tumors. , 1989, Neurosurgery.

[16]  I J Rampil,et al.  Volatile Anesthetics Depress Spinal Motor Neurons , 1996, Anesthesiology.