2 The procedure
2.1.1 Pelviureteric junction obstruction is a congenital or acquired stenosis of the junction between the renal pelvis and the ureter, which inhibits normal urine flow. It can cause chronic or recurrent flank pain as well as urinary tract infections.
2.1.2 Conservative treatment may include long-term use of low-dose antibiotics. Current surgical options to reconstruct and normalise the anatomy of the PUJ include open or laparoscopic pyeloplasty (with or without robotic assistance) and endopyelotomy.
2.2.1 The aim of the procedure is to widen the abnormally narrowed part of the PUJ. With the patient under general anaesthesia and using fluoroscopic guidance, a device containing a monopolar diathermy wire on the surface of a low-pressure tamponade balloon is inserted through the ureter and into the PUJ. The balloon is partially inflated to determine the area of stenosis (seen as a waist in the balloon) and to fix it in position for incision. The diathermy wire incises the target area of the PUJ, through the wall of the ureter, into the periureteric fat. The balloon is fully inflated to apply pressure (tamponade) following incision to promote haemostasis. A stent is inserted across the PUJ, with the aim of maintaining patency, and is removed after several weeks.
Sections 2.3 and 2.4 describe efficacy and safety outcomes from the published literature that the Committee considered as part of the evidence about this procedure. For more detailed information on the evidence, see the overview.
2.3.1 A randomised controlled trial (RCT) of 40 patients treated by electrocautery cutting balloon versus laser endopyelotomy reported a 'successful outcome' (defined as subjective relief or symptom improvement plus objective relief of obstruction and improvement in glomerular filtration rate) in 65% (13/20) and 85% (17/20) of patients respectively at a mean follow-up of 30 months (p = 0.14).
2.3.2 A non-randomised controlled trial of 64 patients reported no significant difference in success rate (defined as relief of symptoms, decreased caliectasis, and diuretic renography half-time values indicating absence of obstruction) between patients treated by electrocautery cutting balloon (78% [21/27]) and those treated by laser endopyelotomy (74% [26/35]) at a mean follow-up of 76 months.
2.3.3 A non-randomised controlled trial of 149 patients reported 'subjective success' (defined as a 50% improvement in preoperative discomfort) in 85% of 52 patients with primary PUJ obstruction treated by electrocautery cutting balloon and 90% of 40 patients treated by antegrade electrode ablation endopyelotomy at a mean follow-up of 16 months (absolute numbers and significance not stated).
2.3.4 The non-randomised controlled trial of 64 patients reported no significant difference in reoperation rates following electrocautery cutting balloon treatment (6% [1/17]), antegrade endopyelotomy (0% [0/18]) or retrograde cold knife endopyelotomy (17% [5/29]) (p = 0.13) (mean follow-up 67 months).
2.3.5 The Specialist Advisers listed key efficacy outcomes as short-term pain relief, resolution of obstruction on imaging and no obstruction recurrence in the long term.
2.4.1 Bleeding requiring transfusion and embolisation of a lower-pole vessel was reported in 7% (2/27) of patients in the electrocautery cutting balloon group compared with 0% (0/37) of patients in the laser endopyelotomy treatment group in the non-randomised controlled trial of 64 patients (p = 0.13). Ureteral bleeding requiring transfusion was reported in 4% (3/76) of patients in a case series of 76 patients treated by electrocautery cutting balloon for PUJ obstruction; embolisation of a lower-pole artery was required in 2 patients. Haematuria (managed conservatively) was reported in 15% (3/20) of patients treated by electrocautery cutting balloon at follow-ups ranging from 2 to 5 days in the RCT of 40 patients.
2.4.2 A case report of 2 patients described 1 patient with a large perirenal haematoma caused by incision of an aberrant renal artery during electrocautery cutting balloon treatment, which was ligated at open surgery, and 1 patient who developed a pseudoaneurysm of an aberrant lower-pole artery, which was embolised.
2.4.3 One case report described a broken cutting balloon wire in the PUJ, which had become calcified and required ureteroscopically-guided laser ablation. Balloon rupture was reported in 1 patient in the RCT of 40 patients.
2.4.4 The Specialist Advisers listed adverse events as infection and need for transfusion.