Clinical Application of Computed Tomography in Discography

Abstract

Discography, the injection of contrast media into the nucleus pulposus, is a diagnostic technique used to evaluate cases of lower back pain, in which the results of other imaging studies are normal or conflicting. The diagnostic merits and applications of lumbar discography have always been controversial and this position is unchanged, even with the advent of computed tomography and magnetic resonance imaging [1–3]. Initially, many believed that MR imaging would eliminate the need for discography; however, with the recognition of multisegmental disc disease on MRI studies and the increased use of spinal fusion procedures, the need for this provocative and morphologic test has grown. Discography, by means of induced pain, is the only neuroradiological examination that presently allows a pathologic disc to be ascertained; it is a precious element in the identification of disc or discs causing the clinical symptoms. Induced pain is not to be confused with the pain provoked by discal distention with consequent stretching of nerve terminals: the latter presents the distinguishing feature of being dull, essentially mechanical and slight in magnitude [4].