Voiding urosonography with second-generation contrast as a main tool for examining the upper and lower urinary tract...

In this series, we analyse the diagnostic efficacy of serial voiding urosonography (VUS) with second-generation contrast, combined harmoniously and specifically with contrast technology, in the examination of the urinary tract in children. This examination includes the diagnosis and follow-up for vesicoureteral reflux (VUR) and urethral disorders, mainly those of the posterior urethral valve (PUV).

After obtaining informed consent, a prospective study was conducted using urosonography with second-generation contrast (sulphur hexafluoride microbubbles, SonoVue®) from November 2014 to October 2015 (1 year) in paediatric patients with suspected VUR or PUV impairment. For patients with a high suspicion of VUR and in cases of PUV, we also conducted simultaneous voiding cystourethrography (VCUG).

We studied 40 patients (80 renal units) between the ages of 2 months and 13 years (median age, 14 months). The indication for the test was a suspected VUR (36 patients, group A) and PUV follow-up (4 patients, group B). The test was correlated with VCUG in 16 patients (12 cases with high suspicion of VUR in group A and with 4 cases of PUV in group B). The visualisation of the urethra was appropriate in cases of dilation or urethral stricture. For 3 of these patients with bilateral VUR demonstrated in the serial VUS, the VCUG showed only unilateral VUR in 2 of the patients and no VUR in 1 of the patients (κ=.73).

We have shown that the visualisation of the urethra is no longer a limitation and that serial VUS can be superior to conventional VCUG in diagnosing VUR.