Sun C, Qi X, Tian Y, et al. – In this study, researchers validated the diagnostic accuracy of ultrasound (US) on gout, and investigated potential risk factors for double-contour sign and tophi formation in patients with gout. The study sample consisted of 117 patients with gout (702 joints). The US analyses were conducted on all knee, ankle, and first metatarsophalangeal (MTP 1) joints to determine the type and location of lesions. The two most outstanding lesion manifestations in knee joints and ankle joints were the double-contour sign and joint effusion. In TMP 1 joints, tophi and double-contour sign were the two most prominent lesion manifestations. Potential risk factors of the double-contour sign and for tophi were factors including uric acid (UA) level and the highest blood UA and age and history of the US, respectively. Hence, in the joints of patients with gout, the US was concluded as an efficient technique. For tophi and double-contour sign, there was US sensitivity in MTP 1 joints. In knee joints and ankle joints, the double-contour sign was a potential particular manifestation. Moreover, UA and the highest blood UA level were potential risk factors for the double-contour sign, whereas for tophi age and US history were potential risk factors.