Spinal MR imaging in suspected metastases: correlation with skeletal scintigraphy

Bone scintigraphy (RN) and magnetic resonance imaging (MR) were prospectively and retrospectively correlated in 64 patients with suspected spinal metastatic disease and possible spinal cord compression. Images were retrospectively interpreted and compared with the prospective official RN and MR reports to help decide relative prospective lesion conspicuity. Spinal lesions were confirmed by radiography, computed tomography, myelography or MR and RN follow-up in 56 patients (88%). Prospectively, MR detected 11 lesions not reported on RN while RN detected two lesions not reported on MR. Retrospective review of RN detected six lesions previously not reported. Retrospectively MR showed all lesions. Those lesions seen only in retrospect by RN were rather subtle and would be difficult to detect prospectively. In general, lesions not well seen on RN had relatively more bone marrow abnormality and less cortical bone involvement. In some cases, MR imaging shows spinal marrow lesions not well seen on planar RN.