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

  • 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
  • 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.

Generally, a RUG/ASU is carried out to visualise anterior urethral abnormalities and a VCUG/MCU for posterior urethral abnormalities.

Additionally, although the bladder is not generally the main target of the exam, as with a cystogram, a VCUG/MCU may be useful in detection of bladder abnormalities and vesico-ureteric reflux (VUR).

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.

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Article information

rID: 27214
System: Urogenital
Synonyms or Alternate Spellings:
  • Urethrogram
  • Ascending urethrography (ASU)
  • Retrograde urethrography
  • Retrograde urethrogram
  • Ascending urethrogram
  • RUG

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Cases and figures

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    Case 1: normal ascending/retrograde urethrogram
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    Case 2: normal descending/voiding urethrogram
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    Case 3: normal retrograde urethrogram (annotated)
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    Case 4: normal VCUG
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    Case 5: normal RUG
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    Case 6: urethra anatomy well shown due to a stricture
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    Case 7: Normal RUG
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    Case 8: pericatheter urethrogram (Normal)
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    Case 9: with Venous intravasation
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    case 10: with venous intravasation
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    Case 11: with venous intravasation
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