Comparison of MRI to contrast CT in the diagnosis of spinal stenosis.

Retrospectively, the MR (magnetic resonance) and contrast CT (computed tomography examinations of 41 patients (123 segments) were objectively scored to evaluate spinal stenosis and disc degeneration. Five categories to evaluate stenosis included the facet joint, foramina, central canal, disc on sagittal section, and disc on axial section. In addition, the ability to demonstrate spondylolysis was compared. The examinations were interpreted by a single observer blinded to the results. Comparisons show 96.6% agreement between MR and contrast CT in the diagnosis of spinal stenosis. Magnetic resonance showed disc degeneration in 74 of 123 segments, while CT showed disc degeneration disease in 27 of 123 segments. Spondylolysis was recognized at three segments on both MR and CT. In conclusion, MR and contrast CT are comparable in their abilities to demonstrate spinal stenosis, and MR is more sensitive in demonstrating disc degeneration.