[Continuous monitoring of somatosensory evoked potentials following spinothalamic tract stimulation in brainstem and spinal cord surgery: case report and literature review].

Abstract

Background: The primary objective of neurosurgical intervention for central nervous system tumors is a balance between optimal tumor resection and minimal postoperative neurological impairment. Intraoperative neurophysiological monitoring is essential in safeguarding somatosensory tracts during surgery. Virtually the only tool for continuous monitoring of sensory pathways is registration of peripheral somatosensory evoked potentials (SSEPs). However, this method has some limitations.

Objective: To increase the quality of intraoperative SSEP monitoring in surgical treatment of brainstem and spinal cord tumors.

Material and methods: To ensure continuous monitoring of sensory pathway function in brainstem and spinal cord surgery, we modified the method for monitoring of SSEPs. Unlike standard technique, we placed two-contact electrode for stimulation either in the area of the bottom of the fourth ventricle or on posterior surface of the spinal cord along the midline. This allows us to stimulate pontine tegmentum or posterior columns of spinal cord.

Results: We demonstrated the feasibility of this method in 2 cases.

Conclusion: The advantage of this method is possible brainstem or spinal cord stimulation reducing the chain of somatosensory tract that is valuable to neutralize the effect of anesthesia on significance of neurophysiological data.