Cyclic voiding cystourethrography: Is vesicoureteral reflux missed with standard voiding cystourethrography?

Abstract

Vesicoureteral reflux (VUR) may occur intermittently and cyclic voiding cystourethrography (VCUG) can enhance the ability of the method to detect reflux. We undertook this prospective study to assess how often VUR may occur intermittently during VCUG and to evaluate the reliability of the method by performing cyclic VCUG. Two hundred seventy-five children younger than 2 years underwent two cycles of VCUG. Ninety-seven refluxing kidney-ureter units (KUU) from 68 children were identified during the two cycles. In 18 children VUR was demonstrated in the first, and in 50 children only in the second, cycle. Discrepancy between the two cycles regarding the presence and/or grade of VUR was observed in 85 KUU from 63 of 275 children (23%). In 21 of these 63 children VUR was > or = grade III. In the presence of reflux in the first cycle, discordant findings in the second cycle were found in 11 of 23 KUU (48%) or in 13 of 18 children (72.2%). In the absence of VUR in the first cycle, the second cycle disclosed reflux in 50 of 257 children (19.5%). In conclusion, intermittent VUR occurred in up to 23% of children undergoing VCUG. In more than one-third of them VUR was of major degree. Cyclic VCUG can enhance the ability of the method to detect and grade reflux.

Interactive magnetic resonance voiding cystourethrography (iMRVC) for vesicoureteric reflux (VUR) in unsedated infants: a feasibility study

“…There were no false-negatives detected by iMRVC, giving a high sensitivity, but 3 renal units were considered positive on iMRVC where they were negative on MCUG, giving a 78% specificity. There are several possible reasons for this discrepancy, whether technical or physiological: VUR may be a transient phenomenon, as techniques such as DRC have different sensitivity to MCUG [24], and repeated bladder filling/voiding cycles increases VUR detection: a second cycle can increase VUR detection by between 12% (CEUS [29]) and 20% (during MCUG [7,9]). The sensitivity of a single-cycle MCUG may be low, but many centres (including ours) perform only one cycle due to concerns about dose, at the expense of potential false-negative results [6], despite three cycles advised in recent European recommendations [30].…”

“…MCUG involves bladder catheterisation, contrast medium instillation and intermittent X-ray fluoroscopic observation until micturition, with postural changes to allow imaging of different parts of the urinary tract (bladder, urethra, ureters and renal pelvis; [6]). The reliability of MCUG is dependent on the severity of reflux: only high-grade reflux is shown at MCUG with 100% reliability, and VUR itself may be intermittent [7][8][9]. MCUG carries a significant radiation burden [10] particularly to the paediatric gonads, and many of the children imaged are normal.…”

Cyclic contrast-enhanced harmonic voiding urosonography for the evaluation of reflux. Can we keep the cost of the examination low?

“…The second cycle of contrast-enhanced VUS was chosen based on previous published data from VCUG indicating that VUR may be an intermittent phenomenon better evaluated when a second cycle is made available. Cyclic VCUG enhances the ability of the method to disclose reflux, as 12-20% of the negative examinations during the first cycle were found to have reflux during the second cycle [10][11][12]. For this reason, cyclic VCUG has been proposed as a standard procedure, at least in cases at high risk for reflux.…”

“…The standard diagnostic method for evaluation of VUR is fluoroscopic voiding cystourethrography (VCUG), although the reliability of this technique has been questioned since VUR may be intermittent [10][11][12]. Therefore, cyclic VCUG has been used to demonstrate reflux in up to 20% of the cases with negative first cycle [10][11][12].…”

Low contrast dose voiding urosonography in children with phase inversion imaging

“…We use a similar approach for routine VCUG in our institution, but unfortunately the number of fillings at VCUG was not recorded. It is well established that the sensitivity of VCUG increases if it is performed with cyclic filling [26][27][28].…”