MAGNETIC-RESONANCE-IMAGING OF THE SPINE IN PLASMA-CELL DYSCRASIAS - AREVIEW

This review of recent data on the techniques and results of spinal mag netic resonance imaging in plasma cell dyscrasias provides a basis for selecting those patients who are most likely to benefit from this inv estigation, Sagittal images should be obtained using T1-weighted spin- echo and T2-weighted gradient-echo sequences, Epiduritis is best detec ted on sagittal or axial images acquired after gadolinium injection us ing T1-weighted spin-echo or phase-opposed gradient-echo sequences, Am ong patients with symptomatic multiple myeloma, 80% have abnormal magn etic resonance images of the lower spine due to plasma cell infiltrati on and this proportion increases with the stage in the Durie and Salmo n staging system, Bone marrow signal abnormalities can be focal, diffu se and homogeneous, or diffuse and variegated. Vertebral fractures due to spinal infiltration or osteoporosis are seen in 48% of cases and s pinal canal narrowing with impingement of bone tumors or epiduritis on nervous structures in 20%, The response to chemotherapy as evaluated based on conventional criteria is fairly well correlated with changes in magnetic resonance imaging findings, Among asymptomatic multiple my eloma patients with normal roentgenograms, 50% have tumor-related abno rmalities on magnetic resonance images of the lower spine, which are a ssociated with an increased likelihood of rapid progression to symptom atic disease, Similarly, one third of patients with an apparently soli tary plasmacytoma of bone have evidence of other plasma cell tumors on magnetic resonance images of the lower spine, and this finding is ass ociated with persistence of monoclonal component production after irra diation therapy, which may be of adverse prognostic significance. Pati ents with monoclonal gammopathies of uncertain significance have no ev idence of tumorous lesions on magnetic resonance images of the lower s pine.