Background/purpose: This report describes a new technique of laparoscopically assisted anorectal pull-through (LAARP) for repair of high imperforate anus. The procedure utilizes minimal perineal dissection, preservation of the distal rectum, and accurate placement of the rectum within the levator ani and external anal sphincter muscle complex.
Methods: Sharp dissection and cautery was used laparoscopically to expose the rectal pouch down to the urethral or vaginal fistula, which was clipped distally and divided. The pelvic floor musculature was then assessed and the levator sling identified. Externally, electrostimulation was used to define the center of the anal dimple. An 8-mm skin incision was made, centered at the strongest cephalad contraction. Using a hemostat, minimal blunt dissection on the perineum was guided by transillumination from the laparoscopic light source. A trocar, consisting of a radially expandable sheath over a Varess needle, was passed through this defined plane in the external sphincter muscle complex and advanced into the pelvis between the 2 bellies of the pubococcygeus muscle, guided by laparoscopic visualization. This perineal trocar therefore formed a passage through the center of the striated muscle complex and levators. The rectal fistula, which had been dissected out laparoscopically, was grasped using the perineal trocar and exteriorized to the perineum. Anorectal anastomosis was performed with absorbable interrupted suture.
Results: Seven patients were treated with initial colostomy in the newborn period followed by delayed LAARP 2 to 12 months later. In 4 newborn infants, the LAARP was performed as a primary procedure without prior colostomy. Laparoscopic mobilization has been possible on all cases attempted. All of the patients have a brisk and symmetric anal contraction with perineal electrostimulation.
Conclusions: Lack of long-term follow-up precludes accurate assessment of the potential for fecal continence. However, short-term experience has been that this new method of pull-through for imperforate anus offers many advantages, including excellent visualization of the rectal fistula and surrounding structures, accurate placement of the bowel through the anatomic midline and levator sling, and minimally invasive abdominal and perineal wounds.