Infiltration patterns of multiple myeloma in MRI

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, T-1-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 objectivated with gadopentotate dimeglumine.