Dalbeth N, et al. - This dual-energy CT (DECT) study was implemented to examine crystal deposition in patients with gout treated with stable-dose allopurinol as well as to identify potential clinical determinants for crystal deposition. Monosodium urate (MSU) crystal deposition was detected, without palpable tophi, in a substantial proportion of patients receiving allopurinol doses ≥300 mg/day for a considerable duration. In addition, a higher frequency and greater volume of MSU crystal deposition were observed in patients with higher serum urate (sUA) and clinical features of severe disease.