Simon Veldhoen MD, Presenter: Nothing to Disclose

Alexander Sauer MD, Abstract Co-Author: Nothing to Disclose

Tobias Gassenmaier MD, Abstract Co-Author: Nothing to Disclose

Bernhard Petritsch, Abstract Co-Author: Nothing to Disclose

Stefan Marco Herz MD, Abstract Co-Author: Nothing to Disclose

Philipp Blanke MD, Abstract Co-Author: Nothing to Disclose

Thorsten Derlin, Abstract Co-Author: Nothing to Disclose

Thorsten Alexander Bley MD, Abstract Co-Author: Nothing to Disclose

Clemens Wirth MD, Abstract Co-Author: Nothing to Disclose

To assess the diagnostic performance of voiding urosonography (VUS) for detection of pediatric vesicoureteral reflux (VUR) when following other procedures requiring application of intravenous contrast.

Iodinated (Iomeprol, Iopamidol) and gadolinium-based (gadoterate meglumine) contrast agents were diluted to bladder concentration and injected into balloons filled with saline solution. MDCT scans were performed to assess the contrast distribution in these phantoms. Regions of interest were placed at the top and bottom side of each balloon and Hounsfield units (HU) were measured. Three other balloons were filled with saline solution and contrast media likewise. An ultrasound contrast agent (UCA) was subsequently added and its distribution in the phantoms was assessed using sonography.

MDCT scans showed a separation of two liquid layers in all bladder phantoms with the contrast layers located at the bottom and the saline solution at the top. Significant differences of the HU measurements at the top and bottom side were observed (p<.001-.007). Following injection of UCA, ultrasound revealed its distribution exclusively among the saline solution at the top of the phantom.

UCA is supposed to be unable to reach the ureteric orifices located at the posterior/inferior bladder wall if excreted contrast material accumulates at the bottom of the bladder. False-negative results of VUS have to be considered if it is performed shortly after imaging procedures requiring intravenous contrast.

Evaluation of VUR utilizing VUS should be performed prior to other procedures requiring intravenous contrast agents.

Veldhoen, S, Sauer, A, Gassenmaier, T, Petritsch, B, Herz, S, Blanke, P, Derlin, T, Bley, T, Wirth, C, Voiding Urosonography Phantom Study: Intravenous Iodinated and Gadolinium-based Contrast Agents May Cause False-negative Results in Assessment of Pediatric Vesicoureteral Reflux.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14010845.html