Voiding cystourethrography


In urology, voiding cystourethrography is a frequently performed technique for visualizing a person's urethra and urinary bladder while the person urinates. It is used in the diagnosis of vesicoureteral reflux, among other disorders. The technique consists of catheterizing the person in order to fill the bladder with a radiocontrast agent, typically diatrizoic acid. Under fluoroscopy the radiologist watches the contrast enter the bladder and looks at the anatomy of the patient. If the contrast moves into the ureters and back into the kidneys, the radiologist makes the diagnosis of vesicoureteral reflux, and gives the degree of severity a score. The exam ends when the person voids while the radiologist is watching under fluoroscopy. Consumption of fluid promotes excretion of contrast media after the procedure. It is important to watch the contrast during voiding, because this is when the bladder has the most pressure, and it is most likely this is when reflux will occur. Despite this detailed description of the procedure, the technique had not been standardized across practices.

Indications

The procedure is often, even usually, conducted on children and being an invasive and uncomfortable, albeit not outright painful, procedure it carries a high potential for psychological trauma for both children and their parents. An increased risk of cancer, in particular genitourinary cancer, has been observed in one study arising from the radiation exposure inherent in the procedure. With respect to post-procedural urinary track infection, the risk has been found to be sufficiently low, except in patients with a pre-existing urologic diagnosis, that pre-operative antibiotic use is not considered a necessary adjunct.