Voiding urosonography with second-generation ultrasound contrast versus micturating cystourethrography in the diagnosis of vesicoureteric reflux

Abstract

Vesicoureteric reflux has been associated with paediatric urinary tract infection. Fluoroscopic micturating cystourethrography (MCU) has been the gold standard of diagnostic test for decades; however, it has been criticized owing to its lower detection rate and radiation dose to children. Therefore, new radiation-free reflux imaging modalities have been developed, in which ultrasound-based contrast-enhanced voiding urosonography (ceVUS) is a good example. However, ultrasonography has been considered as an operator-dependent examination. Therefore, our study aimed to examine the inter-observer agreement of this sonographic technique, which has not been evaluated before. Moreover, the second-generation ultrasound contrast SonoVue has been recently marketed, and the data on its efficacy on intravesical use in ceVUS is relatively scarce. Thus, we also aimed to investigate the diagnostic performance and safety profile of SonoVue-enhanced VUS in the diagnosis of vesicoureteric reflux. Our prospective comparative study compared the diagnostic performance of ceVUS with MCU in young children presenting with first episode of urinary tract infection. We performed sequential ceVUS and MCU examinations in 31 patients (62 pelvi-ureter units). Perfect inter-observer agreement (Cohen’s kappa statistics = 1.0, p < 0.001) was achieved in ceVUS, suggesting its good reliability in reflux detection and grading. Using MCU as reference, ceVUS had 100 % sensitivity and 84 % specificity and carried higher reflux detection rate than MCU (p < 0.001). There was no complication encountered. Conclusion: Voiding urosonography is a reliable, sensitive, safe and radiation-free modality in the investigation of vesicoureteric reflux in children. It should be incorporated in the diagnostic algorithm in paediatric urinary tract infection.

Intrarenal Reflux

“…Vesicoureteral reflux is identified in 30% to 50% of all children, boys and girls, presenting with a first urinary tract infection11 and in 27.4% of siblings of patients with documented VUR 12. Although traditionally VUR is investigated with fluoroscopic VCUG, limited sensitivity due to intermittent fluoroscopy and concerns about childhood radiation exposure have led to the search for an effective, radiation‐free alternative to VCUG 13…”

Accuracy of Cystosonography without Voiding Phase in the Diagnosis of Vesicoureteral Reflux in Children: A Variant of the Original Technique

“…As the VUR is a real-time radiation free technique and the switch from one kidney to contralateral is extremely rapid, the continuous exploration without any pauses captures a higher number of refluxes in both sides. Many authors consider that the VUS with a second-generation contrast agent is superior to conventional fluoroscopic cystography in the detection and grading of VUR [3,5,13]. In addition, the absence of major side effects and low incidence of minor side effects such as dysuria, -not related to the contrast agent, but rather to bladder catheterization-are definite advantages [14].…”

“…Combined use with tissue harmonic imaging that has a high sensitivity for contrast agent [1,2] has improved the diagnostic accuracy of this method, which is nearly 100% in the most recent case studies [3]. VUS, as the standardized technique, is used to acquire information during the bladder filling and voiding phase [4][5][6][7].…”

Contrast-enhanced voiding urosonography (ceVUS) as a diagnostic tool in evaluation of vesicoureteral reflux

“…The second generation of ultrasound contrast agents (UCA) and higher quality ultrasound machines, with contrast-specific software technology, have allowed the application of ceVUS without ionizing radiation (15). ceVUS has become a routine method in the diagnosis of VUR in many European centres, because in recent years there is higher awareness of the potential harmful effects of exposure to ionizing radiation in diagnostic imaging procedures in children (15)(16)(17)(18)(19)(20)(21)(22)(23). Kis et al (25) reported ceVUS to be more sensitive than VCUG since it is a real time imaging method, allowing prolonged, continuous scanning, and thus has the potential to detect intermittent VUR (24).…”