Nineteen cases of cervical syringomyelia, five surgically confirmed, were examined with metrizamide computed tomographic myelography. While a collapsed cord appeared to be a very reliable finding in this series, those cases with distended cords can be studied with sequential scans (at 3 and 24 hr), allowing the distinction between syrinx and cystic intramedullary tumor by the presence or absence of delayed cyst opacification.