Urethrography refers to the radiographic study of the urethra using iodinated contrast media and is generally carried out in males.
When the urethra is studied with instillation of contrast into the distal/anterior urethra it has been referred to as
- retrograde urethrography (RUG)
- ascending urethrography (ASU)
When the posterior urethra is studied during micturation, this has been referred to as
- voiding cystourethrography (VCUG)
- descending urethrography
- micturating urethrography
- pelvic trauma in the emergency department (retrograde only)
- diminished urinary stream
- urethral strictures
- urethral diverticula
- urethral obstruction
- suspected urethral foreign bodies
- urethral mucosal tumors
- suspected urethral fistula
Examination technique (RUG/ASU)
- retract the foreskin and clean the tip of penis with betadine or antiseptic solution
- inject a small amount of topical local anesthetic (e.g. lignocaine gel) into the urethra with a syringe
- local anaesthetic helps to relax the sphincter as the patient may contract it during the procedure thus leading to a diagnosis of a stricture
- some advocate against the use of lignocaine gel on the basis that an inadequate seal is formed
- patient position should be oblique to visualise full length of urethra
- place the tip of the metallic adaptor into the urethral orifice and attach the contrast loaded syringe to it
- an alternative is to place a Foley catheter tip in the navicular fossa and gently inflate the balloon with sterile water until a seal is formed making sure not to cause the patient pain or damage the distal urethra
- inject the contrast and image as soon as a major part of the contrast has been injected, taking spot images when appropriate
Ideal images demonstrate the entire length of the urethra with contrast beginning to fill the bladder.
RUG/ASU vs VCUG/MCU
Generally, a RUG/ASU is carried out to visualise anterior urethral abnormalities and a VCUG/MCU for posterior urethral abnormalities.
In a trauma situation, an RUG/ASU should be performed first. A VCUG/MCU should not be performed first because blindly trying to introduce a Foley catheter into the bladder in a trauma setting may lead to creating additional urethral damage with the catheter.
- 1. Gillenwater JY, Grayhack JT, Howards SS et-al. Adult and Pediatric Urology. Lippincott Williams & Wilkins. (2002) ISBN:0781732204. Read it at Google Books - Find it at Amazon
- 2. Lebowitz RL. Pseudostricture of the urethra: urinal artefact on urethrography. AJR Am J Roentgenol. 1978;130 (3): 570-1. doi:10.2214/ajr.130.3.570 - Pubmed citation
- 3. ALMER PE. URETHROGRAPHY IN THE MALE AND SUPRAPUBIC CYSTOGRAPHY. Br J Radiol. 1964;37 (443): 867-70. doi:10.1259/0007-1285-37-443-867 - Pubmed citation