20 CHAPTER 1  Evaluation of the Urologic Patient

A B

FIG. 1.7  A voiding cystourethrogram performed for the evaluation of recurrent urinary tract infection in this female patient. (A) An oblique film during voiding demonstrates thickening of the midureteral profile (arrows). (B) After interruption of voiding, a ureteral diverticulum is clearly visible extending posteriorly and to the left of the midline (arrows).

well as demonstrating vesicoureteral reflux. The bladder is filled with contrast via catheter (volume varies for children, 200-400 cc for adults). The catheter is removed, and films (AP and oblique) and/or fluoroscopic images are obtained initially, with voiding and post-void. Indications include evaluation of structural and functional bladder outlet obstruction, urethra, and vesicoureteral reflux.

Functional Imaging with Nuclear Scintigraphy

Radionuclide imaging is the procedure of choice to evaluate renal obstruction and function. Common applications for these agents include measurement of renal blood flow, determination of differential renal function, evaluation for the presence and degree of renal obstruction, and assessment of renal scarring.

Technetium 99m –Diethylenetriamine Pentaacetic Acid (99m Tc-DTPA)

•Primarily a glomerular filtration agent useful for evaluation of obstruction and renal function. Upon injection into the blood- stream, 99m Tc-DTPA is extracted by the kidneys entirely through glomerular filtration and is excreted in the urine with- out being reabsorbed.