MRI of Vertebral Compression Fractures: Differentiation between Benign and Malignant Causes

ABSTRACT

PURPOSE: To evaluate the MR image in the differentiation of benign and malignant lesion in compression of the vertebral body. MATERIALS AND METHODS: MR images of 47 benign(acute traumatic within one month:19, chronic traumatic longer than one month or nontraumatic:28) and 21 metastatic compression fractures were respectively reviewed in terms of margin of lesions, signal intensity, paraspinal mass formation, soft tissue change, and involvement of posterior element of vertebra. MR images of TI-(T1WI) and T2*-weighted gradient echo (GE T2WI) sequences were obtained on 0.5T unit in sagittal and axial orientation with 5mm section thickness. RESULTS: The margin of benign compression fracture was usually indistinct (acute fracture:90% (17/19), chronic fracture:68% (19/28)), whereas it was sharply delineated in metastatic compression fracture (92%, (12/13) (p<0.001). Paraspinal mass was seen in both acute traumatic and metastatic compression fractures (acute fracture :26% (5/19), metastatic fracture: 52% (11/21). Soft tissue change was seen only in acute cornpression fractures (58%, 11/19). Involvement of posterior element of vertebra was noted in metastatic fracture (71%, 15/21), acute fracture (32%, 6/19) and chronic fracture (7%, 2/28) CONCLUSION: On MR imaging, involvement of entire portion of a given vertebral body, sharp margin between normal and abnormal areas in partially involved cases, paraspinal mass formation, and posterior element involvement are more frequently seen in metastatic compression fractures, which are considered to be useful in differentiation between benign and malignant causes of compression fracture.