How to perform VCUG after urethroplasty?

Performing VCUG After Urethroplasty

For optimal assessment of urethral healing after urethroplasty, a voiding cystourethrogram (VCUG) should be performed approximately 2-3 weeks following surgery to evaluate for complete urethral healing before catheter removal. 1

Timing of VCUG After Urethroplasty

• A urinary catheter should be placed following urethroplasty to divert urine from the surgical site and prevent urinary extravasation 1
• VCUG is typically performed 2-3 weeks following open urethral reconstruction to assess for complete urethral healing 1
• For anastomotic urethroplasty, VCUG can be safely performed as early as day 3 post-operatively with a low rate of extravasation 2
• For buccal mucosal onlay urethroplasty, VCUG can be safely performed around day 7 post-operatively 2
• In uncomplicated cases, the urethral catheter can be safely removed after 8-10 days postoperatively 3

VCUG Technique After Urethroplasty

Preferred Method: Peri-catheter Retrograde Urethrography (pcRUG) followed by VCUG

• First perform peri-catheter retrograde urethrography (pcRUG) to assess for contrast extravasation before catheter removal 4
• If no significant extravasation is seen on pcRUG, proceed with catheter removal and VCUG 4
• If significant extravasation is detected on pcRUG, maintain the catheter in place and reschedule imaging at a later date 4

VCUG Procedure

1. The VCUG should include a static cystogram to determine:

   • Competency of the bladder neck mechanism 1
   • Level of the bladder neck in relation to the symphysis pubis 1
   • Assessment of the proximal extent of any potential injury 1

2. The clamp method with drip infusion is preferred over the conventional balloon method for contrast administration:

   • Less painful for patients 5
   • Higher success rate in achieving adequate imaging 5
   • Allows for both RUG and VCUG without requiring bladder catheterization 5

Special Considerations

• For pelvic fracture urethral injury (PFUI) cases, VCUG combined with retrograde urethrography (RUG) is essential for preoperative planning 1
• In complex cases or those with suspected proximal injury, consider additional imaging:
  • Antegrade cystoscopy (with or without fluoroscopy) 1
  • Pelvic CT or MRI to assess degree of malalignment and defect length 1

Interpretation and Follow-up

• If extravasation is detected on VCUG, catheter replacement is necessary 4, 3
• Extravasation occurs in approximately 6% of urethroplasties and may indicate a higher risk for stricture recurrence 3
• Clinical signs of impaired wound healing are present in approximately 70% of cases with extravasation 3
• Patients with extravasation may require an additional period of catheterization 3

Pitfalls and Caveats

• Avoid performing VCUG too early after complex urethroplasties, as this may lead to higher rates of extravasation and catheter reinsertion 4, 3
• Be aware that approximately 14% of patients may be unable to void during VCUG examination, which is why starting with pcRUG is advantageous 4
• Radiation exposure is significantly lower with pcRUG compared to VCUG (median 120 vs. 241 mGy/cm²), making it a preferred initial assessment 4
• Longer and more complex strictures may require longer catheterization periods before VCUG 3