A retrograde urethrography is a routine radiologic procedure (most typically in males) used to image the integrity of the

urethra The urethra (: urethras or urethrae) is the tube that connects the urinary bladder to the urinary meatus, through which Placentalia, placental mammals Urination, urinate and Ejaculation, ejaculate. The external urethral sphincter is a striated ...

. Hence a retrograde urethrogram is essential for diagnosis of urethral injury, or

urethral stricture A urethral stricture is a narrowing of the urethra, the tube connected to the Urinary bladder, bladder that allows urination. The narrowing reduces the flow of urine and makes it more difficult or even painful to empty the bladder. Urethral stric ...

Uses

Some indications for retrograde urethrogram are: urethral stricture, urethral trauma, urethral fistula and congenital urethral abnormalities. There is no absolute contraindication for retrograde urethrogram. There are several relative contraindications such as: allergy to

contrast agent A contrast agent (or contrast medium) is a substance used to increase the contrast of structures or fluids within the body in medical imaging. Contrast agents absorb or alter external electromagnetism or ultrasound, which is different from radiop ...

s, acute

urinary tract infection A urinary tract infection (UTI) is an infection that affects a part of the urinary tract. Lower urinary tract infections may involve the bladder (cystitis) or urethra (urethritis) while upper urinary tract infections affect the kidney (pyel ...

, and recent instrumentation of urethra.

Procedure

A low osmolar contrast agent with concentration of 200 to 300 mg per ml with volume of 20 ml can be used in this study. Warming the contrast medium before infusion into the urethra can help to reduce the chance of getting spasm of external urethral sphincter. The subject lies down in a supine position. An 8 Fr Foley catheter is connected to a 50 ml syringe. The syringe is flushed to remove any air bubbles within the Foley catheter and the syringe. The tip of the catheter is then inserted into the urethra using

aseptic technique Asepsis is the state of being free from disease-causing micro-organisms (such as pathogenic bacteria, viruses, pathogenic fungi, and parasites). There are two categories of asepsis: medical and surgical. The modern day notion of asepsis is deri ...

until it is parked inside the navicular fossa. The navicular fossa is located just a short distance proximal to the

urethral meatus The urinary meatus (, ; : meati or meatuses), also known as the external urethral orifice, is the opening of the penis or vulva where urine exits the urethra during urination. It is also where semen exits during male ejaculation, and other fluids ...

within the

glans penis In male human anatomy, the glans penis or penile glans, commonly referred to as the glans, (; from Latin ''glans'' meaning "acorn") is the bulbous structure at the Anatomical terms of location#Proximal and distal, distal end of the human penis ...

. The balloon of the Foley catheter is then inflated with 2 to 3 ml of water to anchor the catheter and occlude the meatus, thus preventing contrast material from leaking out from the penis. Contrast material is then injected from the syringe with

fluoroscopy Fluoroscopy (), informally referred to as "fluoro", is an imaging technique that uses X-rays to obtain real-time moving images of the interior of an object. In its primary application of medical imaging, a fluoroscope () allows a surgeon to see t ...

to visualise the flow of contrast within the penis. The catheter is gently pulled to straighten the penis over the leg of the same side to prevent the overlapping of any pathology in the posterior urethrae. Spot images are taken at 30 to 45 degrees to visualise the entire

spongy urethra The spongy urethra (cavernous portion of urethra, penile urethra) is the longest part of the male urethra, and is contained in the corpus spongiosum of the penis. In humans, it is about 15 cm long, and extends from the termination of the ...

(penile urethra). If there is no contraindication to full urinary catheterisation such as false passage or stricture, the urinary catheter should be inserted until the

urinary bladder The bladder () is a hollow organ in humans and other vertebrates that stores urine from the Kidney (vertebrates), kidneys. In placental mammals, urine enters the bladder via the ureters and exits via the urethra during urination. In humans, the ...

to perform

voiding cystourethrography Urination is the release of urine from the bladder through the urethra in placental mammals, or through the cloaca in other vertebrates. It is the urinary system's form of excretion. It is also known medically as micturition, voiding, ...

to visualise the

prostatic urethra The prostatic urethra, the widest and most dilatable part of the urethra canal, is about 3 cm long. It runs almost vertically through the prostate from its base to its apex, lying nearer its anterior than its posterior surface; the form of ...

and membranous urethra. Filling up the bladder with contrast material without full catheterisation (the end of catheter inside the urethra) is also possible if the subject is able to relax the bladder neck to allow contrast material to flow into the bladder. If a urethral injury is suspected, a retrograde urethrography should be performed before attempting to place a Foley catheter into the bladder. If there is a urethral disruption, a suprapubic catheter should be placed.

Complications

Among the possible complications are: urinary tract infection, urethral trauma, and intravasation of contrast medium (contrast going into blood vessels) if excessive pressure is used to overcome a stricture.

References

External links

New England Journal of Medicine procedure videos: Male Urethral catheterization

Ohio State University Patient Education Materials: Retrograde Urethrogram
Projectional radiography Urologic imaging Urethra {{Treatment-stub

Uses

Procedure

Complications

See also

References

External links