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Teaching NeuroImages: Intraspinal Gouty Tophus

A 49-year-old woman presented to the orthopedic department with a chief complaint of severe low back pain for 2 years, with no neurologic deficiency on physical examination. Laboratory investigations revealed no abnormities. MRI (Figure 1, A and D) showed an intradural mass displacing the posterior spinal cord at the L3 level, leading to lumbar stenosis. Contrast-enhanced MRI (Figure 1, B and E) showed obvious marginal enhancement. CT (Figure 1, C and F) showed that the mass was calcified and the nerve root was compressed. The mass containing tophaceous deposits was removed surgically. As shown in the pathology slide (figure 2), the diagnosis was gouty tophus eventually, which is rarely presented in the spinal canal.1,2 The pain disappeared after the operation.