The C.T. discogram is the C.A.T. scan performed after the discogram is completed and provides anatomic information in different planes that cannot be seen by regular xray on the discogram. (especially axial or top down images) A second injection is not required for this test. The test simply follows the discogram and during which time the contrast was injected. The images may show tearing of the outer covering of the disc in a particular area, diffuse degeneration of the disc or a disc herniation. Theoretically, a normal CT image of the discogram would not be associated with pain.