Chronic urogenital sinus expansion in reconstruction of high persistent cloaca

Soft tissue expansion is a technique useful in reconstruction when a shortage of tissue exists. This study presents an investigation on using chronic balloon expansion in the urethral and vaginal reconstruction of high persistent cloaca.

The common channel was expanded by a balloon, which was progressively inflated over 3-4 weeks at a pressure of 30-50 mmHg until an adequate amount of tissue was obtained. The expanded channel was longitudinally split into anterior and posterior segments: the former was approximated to form a neourethra in continuity with the reconstructed bladder neck and the latter was tubularized to form a vagina.

Twenty-one patients underwent primary posterior sagittal urethro-vaginoplasty using the expanded urogenital sinus. Histologic examination demonstrated that the expanded tissue consisted of a dense fibrous wall lined with a stratified squamous non-cornified epithelium, which was characterized by active cell mitosis and angiogenesis. The patients were followed-up for 0.6-9 year (mean 5.69 ± 2.43 years). All reconstructed urethras, vaginas, and vulvas were satisfactory in color, texture match, and sensation. Urinary continence (grades I and II) was observed in all patients without intermittent catheterization. Two complications were encountered in our study. One patient showed a distal urethral dehiscence and a secondary urethroplasty was performed 6 months after the operation. Another patient developed a redundant urethra upon reaching puberty and urethroplasty was needed.

Chronic balloon expansion allows the formation of adequate tissue similar in appearance and type to the vagina and urethra. It also provides a valuable surgical alternative for the management of high persistent cloaca.