Computed tomography of the knee joint as an indicator of intraarticular tophi in gout.

OBJECTIVE

To evaluate the utility of computed tomography (CT) of the knee joint for detecting intraarticular tophaceous deposits.

METHODS

A prospective study of 16 patients with gout affecting the knee was conducted. A condition for inclusion in the study was the presence of needle-shaped crystals with negative birefringence in the knee joint synovial fluid. Conventional radiography and CT were performed in each case.

RESULTS

Intraarticular opacities in the capsule and the synovium, consistent with the presence of tophaceous deposits, were found in 5 of the 16 patients (9 knee joints). The mean duration of gout was longer in the patients with intraarticular tophi than in those without tophi, and 2 of the patients with tophi had poor tolerance to antihyperuricemic therapy.

CONCLUSION

Intraarticular opacities considered to represent tophi were observed in approximately one-third of the patients. The presence of tophi correlated with a longer duration of the disease and a poor tolerance to medication. We therefore suggest that CT of the knees could be useful in the assessment and followup of certain patients with gout.