Identification of the lumbar intervertebral level using ultrasound imaging in a post-laminectomy patient.

A spinal block was performed in a post-laminectomy patient, using both ultrasound imaging and X-ray imaging. Ultrasound imaging clearly identified the L3/4 intervertebral level, the spinal canal, the corpus vertebrae, and the dura mater. Using ultrasound imaging, we measured the distance from the skin surface to the dura mater (39 mm). A 25-G needle for the spinal block was accurately advanced into the spinal canal with the use of X-ray imaging (43 mm from the skin to the subarachnoid space). We report here that ultrasound imaging was useful for performing a spinal block in a post-laminectomy patient in whom there was anatomical change around the spine.