DIFFERENTIAL-DIAGNOSIS OF BENIGN AND MALIGNANT VERTEBRAL COMPRESSION FRACTURES WITH MR IMAGING - VALUE OF ANTIPHASED LONG TR GRADIENT-ECHO SEQUENCES, STIR SEQUENCES AND GD-DTPA

42 patients with known malignancy and vertebral compressions underwent MRI. Sagittal T1-weighted spin-echo images pre and post Gd-DTPA, out of phase long TR gradient-echo images (GE) and short T1 inversion recovery images (STIR) were obtained at 1.0 T. The results were confirmed by histology (6/42) or clinical data (28/42) and follow up MRI studies (8/42). In 39 of 42 cases a correct differentiation between osteoporotic and tumorous vertebral compression fractures was possible by quantification and correlation of SE and GE signal intensities. Gd-DTPA did not improve differential diagnosis, since both tumour infiltration and bone marrow oedema in acute compression fracture showed comparable enhancement. STIR-sequences were most sensitive for pathology but unspecific due to a comparable amount of water in tumour tissue and bone marrow oedema. Susceptibility-induced signal reduction in GE images and morphologic criteria proved to be most reliable for differentiation of benign and tumour-related fractures. In the rare cases of single and nearly complete vertebral compressions with complete loss of bone marrow, differentiation with MRI was not possible.