Comparison Between Dual-Energy Computed Tomography and Ultrasound in the Diagnosis of Gout of Various Joints

Rationale and Objectives: Dual-energy computed tomography (DECT) and ultrasound are both used to assess gouty arthritis. The present study was designed to compare the diagnostic accuracy of DECT and ultrasound in detecting monosodium urate (MSU) crystal deposition in various joints. Materials and Methods: This study enrolled 40 patients diagnosed with acute gouty arthritis. All affected and contralateral joints were scanned (128 in total) using both DECT and ultrasound to determine the MSU deposition in upper limbs (wrist and elbow) and lower limbs (the first metatarsophalangeal joints, ankles, and knee). The MSU crystal accumulation detected by each method was compared for various joints. Results: The 128 scanned joints included 52 of the upper limbs and 76 of the lower limbs. For the upper limbs, the percentage of MSU crystal accumulation detected by DECT (22/52, 42.3%) was significantly higher than that by ultrasound (10/52, 19.2%; P = .0027). The detection rates of the two methods for the lower limbs were similar (P = .3173). Conclusions: For detection of MSU crystal deposition in the upper limb joints, DECT was superior to ultrasound, whereas there was no difference between the two methods for the lower limbs. Therefore, ultrasound can be used for primary screening, and DECT afterward. Although the modalities are similar in making the initial diagnosis, DECT is far superior at displaying the anatomic extent of the disease.