Detection of multiple myeloma involving the spine: efficacy of fat-suppression and contrast-enhanced MR imaging.

OBJECTIVE: To determine the efficacy of fat-suppressed sequences and contrast-enhanced MR imaging for the detection of focal spinal lesions caused by multiple myeloma, we obtained MR images in 32 patients with newly diagnosed myeloma who had back pain.

SUBJECTS AND METHODS: All patients had biopsy-proved myeloma and had MR imaging at the painful level of the spine. Spin-echo T1-weighted, T2-weighted, and short TI inversion-recovery (STIR) images; dynamic ultrafast low-angle shot (turbo-FLASH) images after IV injection of a bolus of paramagnetic contrast material; and contrast-enhanced T1-weighted images were obtained. We qualitatively compared the signal intensities and contrast enhancement of focal lesions with those of the surrounding vertebral bodies.

RESULTS: Multiple lesions were detected in all but two of the 32 patients. On T2-weighted and STIR images, all lesions had homogeneously high signal intensity. On T1-weighted images, the lesions were visible as hypointense areas compared with surrounding bone in all except four patients, in whom the lesions were isointense or hyperintense. All tumor nodules enhanced on turbo-FLASH images obtained in the arterial phase. No additional lesions were seen on STIR or contrast-enhanced images. MR findings resulted in a change in the staging of the disease in one patient and led to prompt treatment in five patients with epidural involvement.

CONCLUSION: MR imaging appears to be helpful in detecting spinal involvement in patients with multiple myeloma. The diagnosis of spinal lesions is best achieved by using either fat-suppressed or T2-weighted images. Although myeloma lesions enhanced in all patients, contrast material appears to be of no value for the detection of additional lesions.