Clinical utility of dual-energy CT for evaluation of tophaceous gout.

Although diagnosing gout generally is straightforward, atypical disease may present a challenge if it is associated with unusual symptoms or sites, discordant serum urate level, or mimics of gout. Dual-energy computed tomography (CT) may be used to differentiate urate crystals from calcium by using specific attenuation characteristics, which may help diagnose gout. In patients with known tophaceous gout, dual-energy CT may be used for serial volumetric quantification of subclinical tophi to evaluate response to treatment. Given the utility of dual-energy CT in challenging cases and its ability to provide an objective outcomes measure in patients with tophaceous gout, dual-energy CT promises to be a unique and clinically relevant modality in the diagnosis and management of gout.