Our goal was to determine if evidence of cerebrospinal fluid (CSF) leakage on routine postmyelogram computed tomography (CT) of the lumbar spine was useful in predicting subsequent development of moderate or severe headaches in patients having outpatient myelography. We reviewed postmyelogram CT studies of the lower lumbar region of 89 patients for radiographic indication of CSF leakage. These patients had outpatient lumbar myelography. We conducted telephone interviews to determine whether a postmyelographic headache occurred. Correlation of CT-verifiable contrast leakage with subsequent development of postmyelogram headache was statistically significant. The early radiographic identification of such patients affords the opportunity for additional measures, such as extended bed confinement, to decrease the morbidity of myelography. Additionally, statistical correlation of such findings should provide an objective method of evaluating the effectiveness of alterations in myelographic technique.