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Residual intravesical iodinated contrast: a potential cause of false-negative reflux study at contrast-enhanced
Gabrielle C Colleran1, Harriet J Paltiel2, Carol E Barnewolt2
1Department of Radiology, Boston Children's Hospital and Harvard Medical School, 300 Longwood Ave., Boston, MA, 02115, USA. gabrielle.colleran@childrens.harvard.edu.
Abstract:
A 9-month-old girl underwent conventional cyclic voiding cystourethrography (VCUG) followed immediately by cyclic contrast-enhanced voiding urosonography (ceVUS). Although the VCUG showed unilateral grade II reflux, the ceVUS showed no reflux. Images from the ceVUS showed posterior dependent layering of the denser iodinated contrast in the bladder. This layering likely prevented reflux of US microbubbles resulting in a false-negative ceVUS. To our knowledge, this potential pitfall has not yet been reported.
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