The use of intraoperative fluoroscopy and spinal cord monitoring for transoral microsurgical odontoid resection.

The transoral approach to the upper cervical spine has not gained wide acceptance. A reliable intraoperative method to determine the necessary extent of dissection and degree of decompression, as well as to evaluate spinal cord function, should improve the safety and applicability of the transoral approach. Four cases of anterior cervical cord compression were successfully treated by odontoid resection employing a microsurgical transoral approach. Intraoperative fluoroscopy monitored the depth of dissection and adequacy of decompression. Somatosensory cortical evoked potentials (SSEP) allowed assessment of spinal cord function that could be correlated with surgical decompression. In addition, follow-up examination revealed that SSEP was an intraoperative prognosticator of subsequent neurologic improvement.