OBJECTIVETo explore the clinical efficacy of the chronic balloon expansion in urethral and vaginal reconstruction for high persistent cloaca.

METHODSClinical data of 21 children with high persistent cloaca undergoing chronic balloon expansion technique in Cangzhou Central Hospital and Capital Pediatric Institute from December 1996 to August 2014 were analyzed retrospectively. The balloon was continuously expand for 3 to 4 weeks. Balloon was filled with water, maintaining the internal pressure at 30 to 50 mmHg. When the diameter of the common channel was 3 cm, the plastic operations of bladder neck, urethra and vagina were performed.

RESULTSAll the 21 patients underwent primary posterior sagital urethro-vaginoplasty by using the expanded urogenital sinus. The average duration of expansion was (26.8±3.1) days and the average diameter of the urogenital sinus was increased up to (2.8±0.2) cm. Infection of urinary tract and common channel wall was not found. Histological examination demonstrated the expanded tissue consisted of a dense fibrous wall lined by a stratified squamous non-cornified epithelium, which was characterized by active cell mitoses and angiogenesis. Patients were followed up for 0.5 to 11.0 years. Efficacy was satisfactory, and no death occurred. After the operation, 9 cases reached grade I( urinary incontinence, 8 cases reached grade II( among the 17 cases with grade IIII( urinary incontinence. One patient had distal urethral dehiscence, and the secondary urethroplasty was employed six months after the operation. Urethral diameter of another 1 case dilated 9 years later, and a tighten urethral angioplasty was performed, then the urine dripping disappeared. All the children were not treated with vaginal dilatation.

CONCLUSIONChronic balloon expansion allows the creation of adequate tissue similar in appearance and type to vagina and urethra, and provides a valuable surgical alternative for managing high persistent cloaca.