MAGNETIC-RESONANCE-IMAGING IN PATIENTS WITH BONE-MARROW DISORDERS

Magnetic resonance imaging (MRI) provides a non-invasive means to eval uate a large fraction of marrow in less than one hour. Marrow disorder s produce non-specific changes in marrow signal intensities which prim arily reflect changes in proportions of fat and cellular elements. The pattern of these signal changes narrows the differential diagnosis, a nd the combination of these features with the clinical context allows interpretations which are clinically useful in many ways. These includ e: 1) the diagnosis of avascular necrosis (and its distinction from ot her causes of joint pain), 2) detection of osteomyelitis, 3) different ial diagnosis of hypoplastic disorders, 4) staging of lymphomas and my eloma, 5) selection of patients for autologous bone marrow transplant, 6) objective measures of marrow response to therapy, 7) detection of leukemic transformation, and 8) improved detection of marrow disease ( primary or secondary) in patients with otherwise unexplained bone pain .