[Infiltration patterns of plasmacytomas in magnetic resonance tomography].

PURPOSE To define the different infiltration patterns in the spine in multiple myeloma, in correlation with histological and clinical findings. Quantitative signal evaluation with contrast media (Gd-DTPA). To compare the results in MRI with X-ray films. MATERIAL AND METHODS 61 patients with proven multiple myeloma and 50 controls were examined (1.0 Tesla, T1-w SE, opposed phase GE images). RESULTS Five infiltration patterns with different clinical stages were detected: normal bone marrow (11%) in cases of low interstitial marrow infiltration (biopsy), pure diffuse infiltration (25%), focal involvement (33%), combined diffuse/focal infiltration (23%) and a "salt-and pepper" pattern (8%). In diffuse plasmacytoma the 40% signal intensity increase was modification of diffuse infiltration. MRI proved to be more sensitive than radiography. CONCLUSION MRI is able to show the type and the extension of bone marrow infiltration in multiple myeloma. Diffuse involvement can be objective with gadopentetate dimeglumine.