Elster A D, Jensen K M
J Comput Assist Tomogr. 1984 Jun;8(3):533-5. doi: 10.1097/00004728-198406000-00031.
Gas within the cervical spinal canal in association with a surgically proven herniated disc is demonstrated by computed tomography. Although rarely seen and never previously reported, this unmistakable roentgen sign provides strong evidence for a herniated disc in the cervical as well as lumbar spine.