MR-IMAGING FIELD-STRENGTH - PROSPECTIVE EVALUATION OF THE DIAGNOSTIC-ACCURACY OF MR FOR DIAGNOSIS OF MULTIPLE-SCLEROSIS AT 0.5-T AND 1.5-T

PURPOSE: To compare the diagnostic efficacy of middle-field-strength a nd high-field-strength magnetic resonance (MR) imaging in diagnosis of multiple sclerosis. MATERIALS AND METHODS: One hundred thirty-two pat ients with suspected multiple sclerosis underwent MR imaging at 0.5 an d 1.5 T. Imaging parameters were identical except for band width optim ization at middle field strength. Images were interpreted by radiologi sts expert in MR imaging who were blinded to diagnosis and field stren gth. The diagnosis of multiple sclerosis was made by experienced neuro logists, and indeterminate cases and patients without clinical evidenc e of multiple sclerosis were followed up for 6 months to 1 year. RESUL TS: There was no difference in accuracy, sensitivity, or specificity b etween scanners in the diagnosis of multiple sclerosis or white matter disease. Equal numbers of lesions were detected at both field strengt hs in all parts of the brain. Image quality was always good or adequat e at middle field strength.CONCLUSION: Higher field strength does not confer higher accuracy in the diagnosis of multiple sclerosis with cur rent-generation MR imagers.