MR imaging of spondylitis with gadopentetate dimeglumine enhancement

MR images of 17 patients with spondylitis were reviewed. T1 weighted spin-echo scans were obtained in 17 patients and proton density and T2 weighted scans were obtained in 15 patients. Unenhanced and gadopentetate dimeglumine enhanced scans were obtained in all patients. Five patients had pyogenic spondylitis, two patients tuberculous spondylitis, two patients fungal spondylitis and eight patients postoperative spondylitis. The four criteria described by Thrush and Enzmann were generally applicable in our study: 1) narrowing of the intervertebral disc; 2) cortical bone erosion; 3) abnormal signal in the adjacent vertebral bodies and 4) abnormal paraspinous or epidural soft tissue. In addition to plain sagittal T1 and T2 weighted images we suggest the routine administration of gadopentetate dimeglumine to assess the extent of the soft tissue mass and to differentiate postoperative spondylitis from a normal postoperative course, by showing disc enhancement. Disc enhancement occurs infrequently in the normal postoperative course. If it is associated with adjacent vertebral bone marrow changes it should be considered as postoperative spondylitis. A differential diagnosis between pyogenic, tuberculous, fungal and postoperative spondylitis was not possible although the pattern of enhancement in tuberculous spondylitis was different from the other cases of spondylitis.