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Endopyelotomy
Endopyelotomy is a minimally invasive endoscopic procedure that relieves a blockage at the ureteropelvic junction (UPJ) — the point where the kidney’s drainage funnel meets the ureter — by making one precise cut through the narrowed segment and leaving a stent in place while the ureter heals into a wider channel.
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Briefly about this treatment
Indications
Confirmed ureteropelvic junction (UPJ) obstruction causing ongoing flank pain, recurrent urinary infections, kidney stones or worsening hydronephrosis — most suitable when imaging shows a short stricture with no crossing blood vessel.
Risks
Bleeding, infection, and stent-related discomfort or incomplete relief of the obstruction. Risks are minimised by careful patient selection and experienced endourology teams.
Pre-procedure
CT or MR urogram and a diuretic renal scan to confirm the obstruction and check for a crossing vessel, plus standard blood work, an anaesthesia consultation, and fasting per protocol.
Follow-up
Stent removal at around six to seven weeks, follow-up imaging to confirm improved drainage, and longer-term monitoring for recurrence of the obstruction.
What is Endopyelotomy? An expert explains
UPJ obstruction slows or blocks urine as it leaves the kidney, so urine backs up and the kidney’s drainage system stretches (hydronephrosis). Left untreated, that pressure can cause recurring pain, infections, stones, and — over years — a real drop in how well the kidney works.
Endopyelotomy relieves the blockage by cutting the narrow ring of tissue and letting the ureter heal open around a stent, rather than cutting the segment out. Urologists reach the UPJ two ways:
- Antegrade (percutaneous) endopyelotomy — a small tract is made through the skin and kidney; a cold knife, hot knife (electrocautery) or holmium laser cuts the stricture from inside the renal pelvis.
- Retrograde (ureteroscopic) endopyelotomy — a ureteroscope is passed up through the bladder and ureter with no skin incision at all; the same instruments cut the stricture from below.
A 12–14F stent stays across the healing incision for several weeks so the cut edges don’t scar back together as they mend.
Endopyelotomy isn’t the only option. Open, laparoscopic or robotic pyeloplasty — which removes the diseased segment and re-joins healthy tissue — has a higher long-term success rate (around 90–100%) but is more invasive, with a longer recovery. Endopyelotomy is less invasive and remains a good first-line option in carefully selected patients, particularly when there’s no crossing blood vessel over the junction.
Signs it may be time for Endopyelotomy
Your urologist may raise endopyelotomy as an option once UPJ obstruction is confirmed on imaging. On its own, this is a conversation to have with a clinician — not a checklist to self-diagnose from. People in this situation often notice:
- Recurring flank, side or back pain — classically worse after drinking a lot of fluid or alcohol
- Repeated urinary tract infections, or an infection with fever on the affected side
- Blood in the urine (haematuria), with or without an obvious trigger
- Kidney stones forming above the blockage
- A scan (ultrasound, CT or diuretic renal scan) showing worsening hydronephrosis or declining function in the affected kidney
These are the conditions linked to this treatment in the directory. Your clinician decides whether treatment is appropriate using your symptoms, examination and test results.
- Ureteropelvic Junction Obstruction — Blockage between kidney pelvis and ureter.
- Vesicoureteral Reflux Nephropathy — Reflux of urine damages kidney tissue.
- Peripelvic Cyst — Simple cysts near renal pelvis.
- Urachal Cyst — Midline cystic lesion between bladder and umbilicus.
- Obstructive Uropathy — Obstruction of urinary tract affecting kidney function.
Remember: These entries are not a diagnosis or a treatment recommendation. Discuss your symptoms and test results with a qualified clinician.
When to consult a specialist
If you’ve been having ongoing flank pain, repeat urinary infections, or a scan has flagged hydronephrosis, it’s worth getting checked rather than waiting it out — but that doesn’t automatically mean surgery. Plenty of mild, stable cases of UPJ narrowing are simply monitored over time. A basic blood and urine test alongside your existing imaging usually gives a specialist enough to tell you where things stand and what, if anything, comes next.
How a session works
Your urologist confirms the diagnosis and maps the anatomy first — typically a CT urogram or MR urogram plus a diuretic renal scan (MAG-3) to measure how much each kidney is draining and functioning. This imaging also checks for a crossing blood vessel over the junction, since that finding lowers the odds of a good result and may steer you toward pyeloplasty instead. You’ll usually be asked to stop eating and drinking for a set period beforehand and to arrange a ride home, since this is done under general or regional anesthesia.
How a session works (kept)
- Anesthesia. You’re given general or spinal/epidural anesthesia so you feel nothing during the procedure.
- Access. Antegrade (percutaneous) — a small puncture is made in your back into the kidney, under X-ray or ultrasound guidance, and a short tract is dilated to pass instruments directly into the renal pelvis. Retrograde (ureteroscopic) — a thin ureteroscope is passed through the urethra, bladder and ureter — no skin incision at all.
- The incision. Using a cold knife, an electrocautery probe, a holmium laser, or a cutting balloon catheter (the Acucise technique), the surgeon makes one full-thickness cut through the narrowed segment, extending it into the surrounding fat so the ureter can heal in a wider, open position.
- Stenting. A stent (commonly 12–14F) is left across the healing incision, plus — for the antegrade approach — sometimes a temporary drainage tube (nephrostomy) left in the back for a day or two.
- Closing up. The access tract or scope is withdrawn; a percutaneous puncture needs only a small dressing, no stitches to remove.
Session duration
1–2 hours
recorded for this treatment
Cost verify
$8000–$20000
indicative range
Anesthesia
General
recorded for this treatment
Remember: The exact steps, duration and preparation can vary with your indication, health and care setting. Confirm the current plan with your treating team.
Benefits
For well-selected patients, endopyelotomy offers a genuinely lighter path to relieving a UPJ obstruction than open surgery, while keeping the option of pyeloplasty open if it’s ever needed later:
- Minimally invasive — no large abdominal incision; either a single small back puncture or none at all
- Shorter hospital stay and a faster return to daily activity than open pyeloplasty
- Kidney-preserving — treats the obstruction without removing kidney tissue
- A reasonable first-line option in well-selected patients (short stricture, no crossing vessel, good baseline kidney function), with pyeloplasty still available later if needed
- Can treat an associated kidney stone at the same time, in some percutaneous cases
Risks & side effects
Endopyelotomy has risks and trade-offs to discuss with your care team. The information below comes from this treatment’s clinical data. Most people recover without a major complication, but as with any procedure, risks exist:
- Bleeding at the access site — usually minor; uncommonly, heavier bleeding needing a transfusion or, rarely, further intervention if a crossing vessel is unexpectedly injured
- Urinary tract infection or a kidney infection (pyelonephritis)
- Stent-related symptoms — bladder spasms, urinary urgency or frequency, blood-tinged urine, discomfort while the stent is in place
- Urine leakage around the incision site while it heals
- The obstruction not fully resolving, or recurring later — the main reason long-term success rates are lower than with pyeloplasty
- General anesthesia risks, as with any procedure requiring anesthesia
Risks are minimised by careful patient selection and experienced endourology teams.
Who it may not suit: These are general cautions, not a personal verdict. A qualified clinician must assess your full medical picture — including whether imaging shows a crossing vessel, how long the stricture is, and how well the affected kidney is already functioning — before recommending or delaying treatment.
What happens during & after
During: you’re asleep or numbed from the waist down, so you won’t feel the incision. Your care team monitors you throughout.
Right after: you wake in a recovery area; the antegrade approach usually means one to two nights in hospital, while the purely ureteroscopic (retrograde) approach is often done as day surgery or with a single overnight stay. Mild flank discomfort, blood-tinged urine, and stent-related bladder spasms or urgency are expected in the first days and usually ease with simple pain relief.
In the following weeks: the stent stays in for about six to seven weeks while the incision heals over it, then is removed in a short outpatient visit (usually with a light sedation cystoscopy). Imaging is repeated some weeks after stent removal to confirm the kidney is draining well.
Exact technique, anesthesia and stay length depend on your anatomy, your surgeon’s approach and your overall health — your urology team will confirm what applies to you.
Possible complications
A few factors are linked to a lower chance of success, and your urologist weighs these before recommending endopyelotomy over pyeloplasty:
- A crossing blood vessel found over the junction on imaging
- A long stricture (over about 2 cm)
- Significant hydronephrosis at the time of treatment
- Reduced function in the affected kidney beforehand
Remember:
New or severe symptoms require prompt medical advice. Do not wait for a routine appointment if you feel seriously unwell.
Recovery
Most people return to desk-based work within a week or so after endopyelotomy, and to normal, non-strenuous activity within two to four weeks — though this depends on whether you had the antegrade or retrograde approach and how your body heals. Your urology team will give you a specific timeline and tell you when it’s safe to resume exercise, driving, and heavier activity.
When to contact your care team: Call promptly if you notice fever or chills, worsening or one-sided flank pain, heavy (not just tinged) blood in your urine, inability to urinate, or signs of infection at a puncture site. These can signal a treatable complication that shouldn’t wait for a routine follow-up.
Clinics offering Endopyelotomy
Verified kidney centres linked to this treatment in the KidneyGlobal directory.
University Hospital
Urologic Oncology & Robotic Surgery
ISO 9001European Urology Boardda Vinci Robotic Center
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Academic Medical Center
Minimally Invasive Urologic Surgery
Joint CommissionNCI Cancer CenterRobotic Surgery Excellence
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Academic Medical Center
Kidney Transplantation
Joint CommissionUNOS CertifiedLiving Donor Excellence
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Good questions
Most Common Questions
Is endopyelotomy the same as pyeloplasty?
No. Endopyelotomy incises the narrowed segment and leaves it to heal around a stent. Pyeloplasty removes the narrowed segment and stitches healthy tissue back together. Pyeloplasty has a higher success rate; endopyelotomy is less invasive.
How successful is endopyelotomy?
Success is generally reported in the 65–90% range depending on technique, patient selection and length of follow-up, compared with roughly 90–100% for pyeloplasty. Results tend to hold up best in patients without a crossing vessel and with good baseline kidney function.
Can UPJ obstruction come back after endopyelotomy?
Yes, recurrence is possible, more often in the years after treatment than in the first months. If it recurs, repeat endopyelotomy or pyeloplasty are both reasonable next steps.
Is endopyelotomy painful?
Most people have manageable discomfort from the stent (a pulling sensation, urgency, or mild flank pain) during the healing weeks rather than significant pain from the procedure itself.
Will I need a nephrostomy tube?
Sometimes, and usually only briefly. With the antegrade (percutaneous) approach, a temporary drainage tube may be left in your back for a day or two alongside the stent. The retrograde (ureteroscopic) approach typically doesn’t need one at all.
How does the cost of endopyelotomy compare with pyeloplasty?
Published cost analyses generally find endopyelotomy less expensive than either open or minimally invasive pyeloplasty in the immediate period around surgery, reflecting its shorter procedure and hospital stay — though your own cost depends on your country, insurer and hospital.
Sources
- Endopyelotomy for Pelviureteric Junction Obstruction (IPG325)National Institute for Health and Care Excellence (NICE)
- Ureteropelvic Junction Obstruction (Adult)UCSF Department of Urology
- Endopyelotomy Still Has an Important Role in the Management of Ureteropelvic Junction ObstructionCanadian Urological Association Journal (CUAJ)
- Cost Analysis of Treatments for Ureteropelvic Junction ObstructionJournal of Endourology (PMC / NCBI)
- Results of 212 Consecutive Endopyelotomies: An 8-Year FollowupJournal of Urology (PubMed)
- Ureteropelvic Junction (UPJ) ObstructionUPMC