A variety of other chemotherapy agents have been implicated in the development of bone marrow necrosis, including imatinib mesylate and G-CSF. Otherwise, a variety of bone marrow alterations can be encountered on MRI in patients being treated for malignancies. For example, on MRI leukemia can manifest as heterogeneous areas of enhancement (Fig. 38.2), anemia appears as diffuse low T1 and T2 signal due to red marrow conversion (Fig. 38.3), while spinal irradiation produces diffuse high T1 and T2 signal due to fatty marrow conversion (Fig. 38.4).