Disorders of Marrow

As discussed in the previous chapter, the MRI appearance of multiple myeloma in the vertebral axis is variable, ranging from a normal imaging appearance to one indicating focal, multifocal, or diffuse involvement. Within the myeloma spectrum also is the diagnosis of plasmacytoma, which refers to plasma cell proliferation within only a single focus and likely represents an early stage of multiple myeloma. The diffuse pattern involvement in multiple myeloma is illustrated in the sagittal T1WI of Fig. 50.1A. Note that in this case the homogeneous appearance of the vertebral bodies may be misleading—the lack of a focal lesion hindering the detection of abnormality. Thus, it is essential when evaluating sagittal T1WI of the spine to compare the SI of the vertebral bodies to that of the intervertebral disks. Normally, fat content within the vertebral bodies will render them hyperintense to the disks on T1WI. In the present case, however, the vertebral bodies and intervertebral disks are essentially isointense, raising a concern for diffuse marrow pathology. Differential considerations for this appearance include marrow replacement, as in myeloma or metastatic disease, as well as marrow reconversion to a hematopoietic dominance. Lymphoma is another cause of marrow replacement and is illustrated in Fig. 50.1B. Note that this appearance is indistinguishable from that of myeloma (Fig. 50.1A) and that of acute lymphocytic leukemia (Fig. 50.1C

Only gold members can continue reading. Log In or Register to continue