Methods of imaging of the urinary tract

using contrast

Dr. Abdalla Mutwakil GamalRadiology departmentSebha Medical Center

The naming problem

Contents

•Kidneys & Ureters▫Urography

•Urinary bladder▫Cystography

•Urethra▫Urethrography

Urography

Types

•Intravenous urography

•Antegrade urography

•Retrograde urography

When to use each one ?• Intravenous urography

▫ Hematuria, Renal Colic, Recurrent urinary tract infection, Suspected urinary tract pathology.

• Retrograde urography▫ Indications are same as IVU. Retrograde urograms may be

necessary if excretory urograms or CT urogram (CTU) are unsatisfactory, if the patient has a history of adverse reaction to intravenous contrast media, or if other methods of imaging are unavailable or inappropriate.

• Antegrade urograhy▫ Outlining the renal collecting structures and ureters by

percutaneous catheter is occasionally done when excretory or retrograde urography has failed or is contraindicated, or when there is a nephrostomy tube in place and delineation of the collecting system is desired.

Contraindicatons

•Retrograde urography ▫Urinary tract infection▫Pregnancy▫Allergy to contrast

•Antegrade urography▫Uncontrolled bleeding diathesis.

Patient preparation

•Prophylactic antiobiotics •Fasting for 4 h for Antegrade urography

The procedure - positioningRetrograde urography Antegrade urography

The procedure - StepsRetrograde urography

• Supine AP abdomen x-ray• -------------------------------• Cystoscopy• Catheter insertion &

Contrast injection• Taking x-ray films• -------------------------------• Withdrawal uretrograms

Antegrade urography

• Identifying collecting system

• Site of puncture• LA• Puncture & catheter• Oblique and AP images

are taken with gentle introduction of water-soluble contrast medium.

The procedure - Steps

The procedure – Films takenRetrograde urography Antegrade urography

• PA film• Both 35° anterior obliques

of the ureter

• AP film• Both 35° posterior

obliques

The aftercareRetrograde urography Antegrade urography

• Post-anaesthetic observation

• Continue prophylactic antiobiotics

• Dressing site of needle insertion.

• Monitoring Vital signs every 30min for 6 hours.

• Pain management if needed.

Normal Retrograde urogramAdult male with microscopic hematuria and previous technically unsatisfactory excretory urogram.

Transitional cell carcinoma..

Severe deformity with filling defects in right upper pole calices (curved arrow) and blood clots in lower calices and at ureteropelvic junction (straight arrow). 65-year-old man with gross hematuria and right flank pain

Transitional cell carcinoma of the ureter. • No contrast• medium has passed beyond the

large, bulky, right ureteral tumor (arrow). The ureteral widening below the

• tumor is distinctive and is sometimes referred to as the “champagne glass” sign (in this instance, the glass is

• tipped on its side). 76-year-old man with nonfunctioning right kidney.

• Irregular nodular lesions

• Nonspecific ureteritis in a 41-year-old woman. ( A ) Retrograde

• pyelography (RGP) shows irregular nodular elevated lesions in the right

• midureter ( arrow ). Ureteroscopic biopsy revealed nonspecifi c infl ammation

• and the patient’s symptoms improved without specific treatment.

• Antegrade urogram showing 2 filling defects and nephrostomy catheter in right kidney.

• Nephrostogram Fungus balls. Nephrostogram revealing 2 filling defects (arrows) in renal pelvis. Copious fungal

• matter aspirated through nephrostomy catheter. 65-yearold diabetic woman who had undergone left nephrectomy,

• with percutaneous nephrostomy catheter (white arrow) for obstruction of right kidney.

Cystography

Types

•Retrograde cystography

•Voiding cystography

When to use them ?

•Vesicoureteral reflux•Urinary stress incontinence.•Other indications

Contraindicatons

•Active clinical UTI•Pregnancy•Allergy or sensitivity to contrast medium

Patient preparation

•Prophylactic antiobiotics •The patient empties their bladder prior to

the examination.

A boy will need to lie on his back with his legs straight

out on the table

A girl will need to lie on her back with her legs in a "froggy" or "butterfly"

position

The procedure - positioning

The procedure - Steps• Cathetrization • Contrast injection• Monitoring for reflux• Don’t remove the catheter till the patient is going to void.• Spot images are taken during micturition and any reflux

recorded. • Finally, a full-length view of the abdomen is taken to demonstrate

any undetected reflux of contrast medium that might have occurred into the kidneys and to record the post-micturition residue.

• 8. Lateral views are helpful when fistulation into the rectum or vagina are suspected.

• 9. Oblique views are needed when evaluating for leaks.• 10. Stress views are used for urodynamic studies.

The procedure – Films taken• Lateral bladder• Lateral bladder, straining – the catheter is then removed• Lateral bladder during micturation

The aftercare

•Tell patient that dysuria can happen after the procedure

•Give simple analgesia if needed (uine retention due to dysuria)

•If not on antibiotic, and reflux was demonstrated, then give antibiotics

• Vesicoureteric reflux

• Posterior urethral valve in a 7-year-old male child. An oblique VCUG image shows a dilated posterior urethra (arrow) with an abrupt transition to a normal-calibre anterior urethra. Note the bladder neck hypertrophy, the irregular trabeculated bladder wall, and the left-sided grade III vesicoureteric reflux (curved arrow)

• Large posterior urethral diverticulum in an 8-year-old male child presenting with recurrent urinary tract infection. An oblique VCUG image reveals a large wide-neck diverticulum (*) arising from the prostatic urethra

Voiding Cystourethrogram• (a) Micturating cystogram:

left diverticulum without ureterovesical reflux, (b) Micturating cystogram: Post voiding view left diverticulum and post voiding residue

Retrograde cystography - Indications

•Bladder cancer•Vesicoureteral reflux•Bladder polyps, and•Hydronephrosis.

The procedure• Using a urinary catheter,

radiocontrast is instilled in the bladder, and X-ray imaging is performed.

• In adult cases, the patient is typically instructed to void three times, after which a post voiding image is obtained to see how much urine is left within the bladder, which is useful to evaluate bladder contraction dysfunction. A final radiograph of the kidneys after the procedure is finished is performed to evaluate for occult vesicoureteral reflux that was not seen during the procedure itself.

Some common abnormal findings

• Conventional cystogram demonstrating an intraperitoneal bladder rupture.

• Cystography revealed a fistula tract between the contracted urinary bladder and the terminal ileum.

• Exstrophy of the urinary bladder on retrograde

cystography.

Urethrography

Indications

•Suspected injury of the urethra•Diminished urinary stream•Urethral strictures•Urethral diverticula•Urethral obstruction•Suspected urethral foreign bodies•Urethral mucosal tumors•Suspected urethral fistula

Contraindications Preparation

• Urinary tract infection• Recent instrumentation

• None is needed

The procedure - positioning• The patient should be

positioned obliquely at 45 º with the bottom leg flexed 90 º at the knee and the top leg kept straight. Alternatively, the patient can be supine.

The procedure - Steps

•Sterilization•Contrast injection and immediately take

the x-ray.• ideal film demonstrates entire length of

urethra with contrast beginning to fill the bladder

Some common abnormal findings

• Conventional Retrograde Urethrogram (RUG) following trauma showing urethral injury.

• Note diastasis (i.e., widening) of symphysis pubis (line between two halves of symphysis) related to traumatic injury. Injuries involving the low pelvic ring have a high associated injury rate to the urethra. In this RUG, the urologist is instilling contrast into the urethra at the tip of the penis through a Tummey (SP?) syringe (S). Contrast shows a normal anterior urethra but the contrast does not fill the posterior urethra and stops abruptly at the level of urethral injury at the urogenital diaphragm (arrow). This is the most common level of urethral injury due to the relatively fixed position of the urethra resulting in sheer or distraction urethral injury with pelvic trauma.

• These two radiographs demonstrate why the retrograde urethrogram is the preferred method of demonstrating the urethra. Retrograde filling of the urethra demonstrates the urethra better than with a voiding cystourethrogram. Notice that there is transection of the urethra and extravasation of contrast (white arrows).

• Anterior urethral stricture. Retrograde urethrogram reveals a segment of narrowing in the distal bulbous urethra with opacification of the left Cowper duct (arrow).