What procedures can aid in the diagnosis and treatment of urinary obstruction?
Cystourethroscopy (endoscopic visualization of the urethra and bladder) can identify urethral strictures and/or prostatic hyperplasia that may be causing bladder outlet obstruction.
If other imaging studies are equivocal or patients are unable to receive intravenous contrast administered (due to severe chronic kidney disease (CKD) or allergy), a retrograde pyelography (injection of contrast up the ureters during cystoscopy) may be necessary.
Retrograde pyelography provides excellent delineation of filling defects within the ureter, renal pelvis, or renal calyces. Collection of urinary cytology is possible during retrograde pyelography.
Cystoscopy also allows for intervention to relieve ureteral obstruction in the same setting, such as placement of a ureteral stent.
If a ureteral stent is unable to bypass a ureteral obstruction or does not provide adequate drainage of the kidney collecting system, a percutaneous nephrostomy tube may be necessary to optimize kidney decompression.