With magnetic resonance imaging and computed tomography, there now are two excellent diagnostic imaging modalities to detect noninvasively the presence of lumbar disc abnormalities and to follow the natural history of pathologic changes of a disc, with or without therapeutic interventions. The clinical significance of the information provided by these two imaging methods can be determined only by precise correlation of the results of a magnetic resonance imaging or computed tomography study to a patient's history, physical examination, and other diagnostic tests. With controlled prospective clinical studies, it may be possible to learn what type of abnormal changes detected on a magnetic resonance imaging or computed tomography study may have prognostic value in predicting patient outcome.