Intraoperative ultrasonographic evaluation of the spinal cord in cervical myelopathy.

Intraoperative spinal ultrasonography (IOSS) was used to evaluate and monitor the spinal cord in 49 patients with cervical myelopathy. Intraoperative spinal ultrasonography demonstrated movements of the dura mater and the spinal cord at the cardiac rate, with some variability in intensity and mode. It also delineated the anterior surface of the spinal canal and configuration of the spinal cord. Statistical analysis showed no correlation between clinical outcome and morphologic restoration, and between clinical outcome and variations in intensity or mode of the pulsatile spinal cord movements. Spinal cord motions were surmised to be generated not only by the anterior spinal artery, but also by other factors. Dural pulsations clearly did not always imply the absence of compression of the spinal cord. Intraoperative spinal ultrasonography was thus quite useful for monitoring decompression in cervical myelopathy.