Urethrography

Retrograde urethrography is commonly considered the imaging modality of choice to evaluate urethral injury. The sensitivity of this technique, however, is controversial. While some authors assess that virtually all urethral injury can be identified (Koifman et al. 2003), in other published series a lower efficiency has been demonstrated (Mydlo et al. 1998). 

Mydlo JH, Hayyeri M, Macchia RJ (1998) Urethrography and cavernosography imaging in a small series of penile fractures a comparison with surgical findings. Urology 51 616-619... 

Traditional radiological exams such as retrograde urethrography and micturition cystourethrography are considered the standard imaging techniques for... 

Retrograde urethrography is commonly used to explore the anterior urethral anatomy and pathologies, but recently sonourethrography has been increasingly proposed. The latter is able to study the urethral mucosa and the periurethral tissues possibly involved in urethral pathologies such as strictures, diverticula, trauma and tumors, which cannot be detected radiographically or at urethroscopy. 

Stenoses due to pelvic fracturing, on the other hand, affect almost exclusively the membranous urethra. They can be easily investigated with retrograde urethrography and voiding cystourethrography, but are difficult to explore with sonourethrography. 

Retrograde urethrography is the best way to study fistulae located under the striate sphincter of the urethra since it can visualize the fistula, the concomitant cavities and passage of the contrast agent into adjacent organs. 

CT has a limited role in the evaluation of the urethra. Certain urethral abnormalities such as calculi or diverticula may be incidentally discovered at CT performed for other indications. CT is useful in patients with pelvic trauma (Chou et al. 2005) and associated urethral injuries and for staging of urethral carcinoma. CT virtual cystoscopy and voiding urethrography can be indicated in patients with complex urethral strictures and malformations. 

Merchant SA, Amonkar PP, Patil JA (1997) Imperforate syringoceles of the bulbourethral duct appearance on urethrography, sonography, and CT. AJR Am J Roentgenol 169 823-824... 

Morey AF, McAninch JW (1997) Role of preoperative sono-urethrography in bulbar urethral reconstruction. J Urol 158 1376-1379... 

Nash PA, McAninch JW, Bruce JE, Hanks DK (1995) Sono-urethrography in the evaluation of anterior urethral strictures. J Urol 154 72-76... 

Yekeler E, Suleyman E, Tunaci A et al (2004) Contrast-enhanced 3D MR voiding urethrography preliminary results. Magn Reson Imaging 22 1193-1199... 

Babnik Peskar D, Visnar Perovic A (2004) Comparison of radiographic and sonographic urethrography for assessing urethral strictures. Bur Radiol 14 137-144... 

Retrograde urethrography is rarely indicated, and retrograde or suprapubic VCU should be preferred in most patients. Such an examination is usually performed to rule out a ruptured urethra in an adolescent. A Foley catheter is inserted in the distal urethra. The balloon is then inflated in the fossa navicularis, and the urethra is slowly and retro-gradely injected. Lateral and oblique pictures are taken. In most instances, the posterior urethra is not opacified. This should not be considered abnormal. 

Bates CP, Whiteside CG, Turner-Warwick RT (1970) Synchronous cine pressure flow cysto-urethrography, with special reference to stress and urge incontinence. Br J... 

Fig. 6.10. Urethrography in an adolescent boy. Normal visualization of Cowper s glands...

A great variety of urethral abnormalities may be found, most of them in boys. Evaluation is based on VCU or urethrography. Endoscopy is often useful. Normal variants should be kept in mind in order to avoid misinterpretation. For example, compression of the pendulous urethra by a nonopaque urinal and proximal dilatation is a frequent cause of error (Rink and Mitchell 1990). 

Fig. 25.13. Retrograde urethrography. Urethral stenosis following a long-standing urethral catheterization for cardiac surgery. Note reflux into the prostatic ducts...

Fig. 25.15. Complete disruption of the membranous urethra in an adolescent boy shown by retrograde urethrography (arrow). Note the inflated balloon of the Foley catheter in the fossa navicularis...

---