Introduction to the technique of anterior vaginal wall - Urethra - Bladder neck complex preserving with introitoplasty (AVUBI -preserve) for cloacal reconstruction.

AIM: To review the need for secondary major urogenital reconstruction of a novel function preserving technique, AVUBI-preserve for cloacal reconstruction and to compare the results with that using conventional techniques.

METHODS

A retrospective cohort study was performed in patients who underwent definitive cloacal reconstruction at a single tertiary paediatric surgical centre between 1988 and 2018, with follow-up until 2023. Patients were included if follow-up data regarding the need for major secondary surgical intervention were available. Major secondary surgery was defined as redo cloacal reconstruction, redo vaginoplasty, or urinary diversion/continence surgery. Patients were divided into two groups according to the primary reconstructive technique: 1. Conventional cloacal reconstruction using total urogenital mobilisation (TUM) and/or urogenital sinus separation (UGS) with vaginoplasty. 2. AVUBI-preserve reconstruction involving in situ preservation of the anterior vaginal wall-urethra-bladder neck-introitus complex with selective reconstruction of the posterior vaginal wall and introitus. Redo rates were compared using Fisher's exact test, with statistical significance set at p < 0.05.

RESULTS

A total of 98 patients were included. Eighty-six underwent conventional reconstruction and 12 underwent AVUBI-preserve reconstruction. Median age at reconstruction was comparable between groups (Mann-Whitney U test, p = 0.84). Major secondary urogenital surgery was required in: · 36/86 patients (41.9%) in the conventional group. · 2/12 patients (16.7%) in the AVUBI-preserve group. These difference did not reach statistical significance (Fisher's exact test, p = 0.12). The relative risk of major redo surgery after AVUBI-preserve reconstruction was approximately 0.4, corresponding to an estimated 60% relative reduction in redo risk. Notably, no patient in the AVUBI-preserve group required redo cloacal reconstruction, compared with 7/86 patients (8.1%) in the conventional group, although this did not reach statistical significance.

CONCLUSION

This study did not show a significant difference in the rate of secondary urogenital reconstructions between the function-preserving AVUBI-preserve technique as compared to conventional techniques. The clinical impression of possible lower need for redo cloaca surgery and secondary urogenital reconstructions needs further evaluation from a larger pool of patients and further evaluation in a larger multicentre study.