What are the indications, technique, and post‑procedure care for a cystoscopy with retrograde pyelogram?

Cystoscopy with Retrograde Pyelogram: Clinical Protocol

Primary Indications

Retrograde pyelogram (RPG) combined with cystoscopy is indicated primarily for suspected ureteral injuries (especially iatrogenic), trauma evaluation, and when detailed collecting system visualization is imperative in patients with contraindications to CT or MRI. 1

Specific Clinical Scenarios Requiring RPG:

• Suspected iatrogenic ureteral injury during surgery – This is the gold standard diagnostic approach and should be performed intraoperatively when ureteral injury is suspected 2, 1
• Trauma evaluation of the urinary tract when CT is unavailable or contraindicated 2, 1
• Positive cytology with negative cystoscopy – Consider RPG along with prostatic urethral biopsies, enhanced cystoscopy techniques, ureteroscopy, or random bladder biopsies 2
• Upper tract tumor evaluation – When assessing renal pelvic or ureteral tumors, particularly to pinpoint sources of positive cytology 2
• Patients with renal insufficiency where intravenous contrast is contraindicated 2, 1
• Pregnant patients with suspected urinary tract pathology, combined with ultrasound to minimize radiation exposure 1

Equipment Requirements

The procedure requires fluoroscopic equipment, an operating room with radiation-shielded walls, and a C-arm compatible operating table 1. A 5-Fr universal ureteral catheter is typically used for cannulation 3, 4.

Technique

Procedural Steps:

• Patient positioning: Place patient in dorsal lithotomy position on fluoroscopy-compatible table 3
• Cystoscopy first: Perform thorough cystoscopic examination of entire urethra and bladder, documenting tumor size, location, configuration, number, and mucosal abnormalities 2
• Ureteral catheterization: Use a 5-Fr ureteral catheter to cannulate the ureter under direct visualization 3, 4
• Contrast injection: Inject 6-8 ml of water-soluble contrast (typically 76% meglumine diatrizoate diluted 1:2) in a retrograde fashion under fluoroscopic guidance 3, 4
• Imaging: Obtain fluoroscopic images showing opacification of the collecting system 3

Critical Technical Points:

• Avoid bilateral RPG in the same sitting in patients with baseline renal insufficiency (creatinine >1.5 mg/dl) due to risk of acute renal shutdown 4
• If urethral injury is suspected, perform retrograde urethrography before bladder catheterization to avoid worsening urethral disruption 2, 5
• During emergency laparotomy, if ureteral injury is suspected, direct inspection should always be performed; cystotomy for retrograde cannulation is an option if standard positioning is not feasible 2

Post-Procedure Care

Immediate Monitoring:

• Monitor urine output closely in the first 24 hours, especially after bilateral procedures 4
• Check serum creatinine on postoperative day 1 if bilateral RPG was performed or if baseline renal function was impaired 4
• Watch for signs of contrast reaction, including hypotension, hypoxia, or allergic manifestations 2

Complications to Anticipate:

• Anuria/acute renal shutdown: Rare but serious complication, particularly with bilateral procedures in patients with baseline renal insufficiency; may require hemodialysis 4
• Infection: Monitor for signs of pyelonephritis or urosepsis 3
• Ureteral perforation: Recognize by extravasation of contrast outside the ureteral lumen 3

Follow-up Imaging:

• For upper tract tumors (pT0-pT1), perform serial cystoscopies at 3-month intervals for the first year, then every 6 months; upper tract imaging (IVP, RPG, or CT/MRI urography) at 1-2 year intervals 2
• For higher stage tumors (pT2-pT4), more intensive surveillance with serial urothelial tract evaluations and metastatic disease screening 2

Important Caveats

CT urography with delayed phase is less sensitive and specific than retrograde cystography for detecting bladder injuries 2, 5, so do not rely on CT alone when bladder perforation is suspected.

The yield of RPG for incompletely opacified ureteral segments on CT urography is low (2.7%) if the ureters appear otherwise normal and there is no hydronephrosis 6. In such cases, RPG may not be necessary unless there are additional concerning features.

Intravenous urography may be useful in unstable patients during surgery when kidney injury is found intraoperatively or when CT is unavailable 2, but RPG remains superior for detailed ureteral evaluation 2.