To compare the sensitivities of individual and combined sonography of hyperechoic aggregates and the double-contour sign in detecting monosodium urate (MSU) crystal deposits in gouty joints.
Monosodium urate crystal deposits in symptomatic and contralateral asymptomatic joints of 70 patients with acute gout were evaluated by sonography of hyperechoic aggregates and the double-contour sign individually and in combination. All patients with acute gout in this study had at least 1 symptomatic joint with MSU deposits determined by dual-energy computed tomography.
Of 195 symptomatic joints (92 in the upper limbs and 103 in the lower limbs) and an equal number of asymptomatic joints: (1) 97.14% (68 of 70) of patients had hyperechoic aggregate/double-contour sign-positive joints versus 74.29% (52 of 70) with double-contour sign-positive and 63.89% (46 of 70) with hyperechoic aggregate-positive joints; (2) 86.96% (80 of 92) of the symptomatic upper limb joints were double-contour sign/hyperechoic aggregate positive versus 46.74% (43 of 92) that were double-contour sign positive and 70.65% (65 of 92) that were hyperechoic aggregate positive; and (3) 98.06% (101 of 103) of the symptomatic lower limb joints were double-contour sign/hyperechoic aggregate positive versus 92.23% (95 of 103) that were double-contour sign positive and 41.75% (43 of 103) that were hyperechoic aggregate positive.
Hyperechoic aggregates and the double-contour sign in combination improve the investigative sensitivity of sonography than either hyperechoic aggregates or the double-contour sign individually for detecting MSU crystal deposits in gouty joints.