Primary Obstructive Megaureter: Initial Experience with Endoscopic Dilatation

Institut Marqués, Spain, Barcelona, Barcino, Catalonia, Spain
Journal of Endourology (Impact Factor: 1.71). 10/2007; 21(9):999-1004. DOI: 10.1089/end.2006.0122
Source: PubMed


Primary obstructive megaureter (POM) without vesicoureteral reflux has classically been managed by open surgery with ureteral reimplantation. We present seven patients with POM who were treated endoscopically with balloon dilatation of the distal ureter.
Six boys and one girl with POM were treated from June 2000 through July 2004. Six of the cases were diagnosed prenatally when ectasia of the urinary tract was seen on ultrasound scans. The postnatal diagnosis was also achieved by ultrasonography, along with a diuretic isotopic renogram with MAG-3, intravenous urography, and filling cystography. The age at surgery was 1 to 3 years. In all cases, a compact 10F infant cystoscope with a 5F working channel was used. Dilatation of the stenotic area was performed under fluoroscopic monitoring. A 4F dilating balloon was used, which was insufflated to between 12 and 14 atm for 3 to 5 minutes, and disappearance of the narrowed ring was verified. A Double-J catheter was positioned and withdrawn 2 months after the procedure. Clinical, analytical, and imaging follow-up was carried out with ultrasonography and MAG-3 renography.
The mean follow-up of the patients is 31 months (range 12-56 months). Their clinical progress was highly satisfactory. Five patients exhibited reduced obstruction at MAG-3. One patient needed a second dilatation, and the obstructive curve improved after this additional procedure. One of the patients presented with a febrile urinary infection after the dilatation, but there were no other complications.
Endoscopic management of POM by balloon dilatation has yielded very good results in the short term. Longer follow-up will enable us to determine the final indications for this treatment.

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    • "Congenital megaureter is a term used in many cases of urinary tract dilation detected before and after birth (Shokeir AA et al 2000). In children, the ureteral diameter is usually not >5 mm, and when it is >7 mm, it could be considered a megaureter (Angerri O et al 2007). The studies by Payabvash et al. (Payabvash S et al 2007) and Kajbafzadeh et al. (Kajbafzadeh AM et al 2006) revealed that the proportion of muscular content in the ureteral wall of an obstructed vesicoureteral junction is significantly lower than that in normal specimens. "
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