Perineal skin bridge and levator muscle preservation in neutral sagittal anorectoplasty (NSARP) for vestibular fistula

Abstract

The incision in limited posterior sagittal anorectoplasty for vestibular fistula (VF) extends from the coccyx to the fistula with the rectum identified by partial sagittal division of the levator muscle. In anterior sagittal anorectoplasty, the perineal incision extends from the fistula opening to the posterior margin of the external sphincter complex while preserving intact the levator muscle. We describe a modification of the operation for repair of VF, the neutral sagittal anorectoplasty (NSARP), which preserves both a perineal skin bridge between the neo-anus and the posterior fourchette and the levator muscle. Leaving the perineal skin bridge and the levator muscle intact could be important both from the aspects of perineal wound-healing and functional outcome. The skin incision in NSARP extends from the coccyx to the anterior limit of the external sphincter muscle complex as defined by muscle stimulation. An artery forceps passed through the VF facilitates the location and exposure of the rectum. The levator muscle is left intact. The dissection and closure of the VF is done entirely from within the opened rectum. There is an intact perineal skin bridge between the neo-anus and the posterior fourchette at the completion of the NSARP. In 12 consecutive patients with VF, NSARP prevented the risk of wound complications occurring between the neo-anus and the posterior fourchette. A diverting colostomy was safely avoided in our last five patients. NSARP does not involve any division of the levator muscle and it also retains an undisturbed wad of tissue that could function as the perineal body. All five patients who are 3 years or older demonstrate voluntary bowel movements. Preserving the perineal skin bridge and the levator muscle in NSARP have contributed to the improvement of aesthetic appearance of the perineum and faecal continence in our patients.