title: Contrast-enhanced voiding urosonography phantom study: intravenous iodinated and gadolinium-based contrast agents may cause false-negative results in assessment of vesicoureteral reflux in children.
abstract: BACKGROUND
  Contrast-enhanced voiding urosonography (ce-VUS) is commonly requested simultaneously to other diagnostic imaging necessitating intravenous contrast agents. To date there is limited knowldedge about intravesical interactions between different types of contrast agents.
  
  
  OBJECTIVE
  To assess the effect of excreted intravenous iodinated and gadolinium-based contrast agents on the intravesical distribution of ultrasound contrast within contrast-enhanced voiding urosonography.
  
  
  METHODS
  Iodinated (iomeprol, iopamidol) and gadolinium-based (gadoterate meglumine) contrast agents were diluted to bladder concentration and injected into balloons filled with saline solution. CT 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. The ultrasound contrast agent sulphur hexafluoride was added and its distribution was assessed using sonography.
  
  
  RESULTS
  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 < 0.001-0.007). Following injection of ultrasound contrast agent, US showed its distribution exclusively among the saline solution.
  
  
  CONCLUSIONS
  False-negative results of contrast-enhanced voiding urosonography may occur if it is performed shortly after imaging procedures requiring intravenous contrast.
authors: Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080, Würzburg, Germany, veldhoen_s@ukw.de.
authors: Simon
authors: S
authors: Veldhoen
authors: Alexander
authors: A
authors: Sauer
authors: Tobias
authors: T
authors: Gassenmaier
authors: Bernhard
authors: B
authors: Petritsch
authors: Stefan
authors: S
authors: Herz
authors: Philipp
authors: P
authors: Blanke
authors: Thorsten
authors: T
authors: Derlin
authors: Thorsten A
authors: TA
authors: Bley
authors: Clemens
authors: C
authors: Wirth
mesh_terms: D000283:Administration, Intravesical; D003287:Contrast Media; D005188:False Negative Reactions; D006801:Humans; D007275:Injections, Intravenous; D007479:Iopamidol / Q000008:administration & dosage / Q000031:analogs & derivatives; D008536:Meglumine / Q000008:administration & dosage; D061330:Multidetector Computed Tomography; D009942:Organometallic Compounds / Q000008:administration & dosage; D019047:Phantoms, Imaging; D013459:Sulfur Hexafluoride / Q000008:administration & dosage; D014463:Ultrasonography; D014718:Vesico-Ureteral Reflux / Q000000981:diagnostic imaging*
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C057937:iomeprol; D008536:Meglumine; D007479:Iopamidol; C072417:gadoterate meglumine; D013459:Sulfur Hexafluoride
references: Radiology. 2010 Aug;256(2):406-14
references: 20529990
references: Eur J Radiol. 2011 Nov;80(2):373-7
references: 21376497
references: Radiology. 1999 Jan;210(1):201-7
references: 9885609
references: Pediatr Radiol. 2012 Jun;42(6):660-7
references: 22580901
references: Pediatr Radiol. 2009 Mar;39(3):239-44
references: 19096835
references: Ethiop Med J. 2013 Apr;51(2):153-60
references: 24079159
references: Pediatr Radiol. 2008 Jan;38(1):54-63; quiz 126-7
references: 17639371
references: Radiologe. 2005 Oct;45(10):915-23
references: 15971042
references: Eur J Radiol. 1994 May;18 Suppl 1:S51-60
references: 8020519
references: J Magn Reson Imaging. 2009 Dec;30(6):1259-67
references: 19938038
references: Radiol Clin North Am. 2013 Jul;51(4):583-98
references: 23830787
references: Pediatrics. 1981 Mar;67(3):392-400
references: 7017578
references: Pediatr Radiol. 2012 Dec;42(12):1471-80
references: 23052725
references: Ann Radiol (Paris). 1966;9(1):37-40
references: 5930070
references: Pediatr Radiol. 2013 Sep;43(9):1063-73
references: 23843130