Calcification demonstrated as high signal intensity on T1-weighted MR images of the disks of the lumbar spine.

PURPOSE: To report that calcification of lumbar disks may not show the usual low signal intensity on T1-weighted magnetic resonance (MR) images. MATERIALS AND METHODS: The authors present five cases of high signal intensity on T1-weighted MR images of a lumbar disk that reflect the presence of calcium deposition. RESULTS: In four cases there was conventional radiographic confirmation and in one case there was computed tomographic confirmation of the disk calcification, which corresponded to the high signal intensity seen on the MR studies. One patient had undergone surgical removal of a partially calcified protruding disk. CONCLUSION: Lumbar disk calcification can vary in signal intensity from low to high on T1-weighted MR images.