At the 1991 meeting of the Eastern Section of the Triological Society, Myles L. Pensak, MD, Robert W. Keith, PhD, John M. Tew, Jr, MD, and Harry VanLoveren, MD, University of Cincinnati (Ohio) Medical Center, discussed monitoring brain-stem function during skull base surgery using somatosensory cortical evoked potentials (SCEP). Traditionally, the auditory brain-stem response (ABR) is used to monitor the neurologic status of patients during brain-stem manipulation in removal of skull base lesions. The SCEP can be used when the ABR is not present or when it is at high risk of being lost during the operative procedure.
Both ABR and SCEP impulses travel through separate pathways within the brain stem within a relatively small area of the neural axis. The SCEP can be recorded with the same averaging computer used for the ABR study.
The investigation group included 66 patients who underwent skull base excision of tumor lesions. Twenty-four