Transanal Pull-Through With or Without Laparoscopic Assistance for Rectosigmoid Hirschsprung’s Disease

Abstract

To ensure good postoperative bowel function (POBF) following transanal pull-through (TAPT) for Hirschsprung’s disease (HD), transanal dissection should commence just proximal to the anorectal line (ARL), leaving the ARL intact and preserving the anal transitional zone (ATZ). Because the ARL is a readily identifiable landmark, transanal dissection will thus become standardized with reliable and reproducible results. In addition, the posterior rectal muscle cuff above the ARL should be excised completely to fully release achalasia due to an aganglionic rectum while preserving the ARL and the ATZ.

In contrast, when the dentate line (DL) is used, transanal dissection may commence anywhere from 5 to 20 mm above the DL depending on the surgeon’s subjective preference resulting in a spectrum of outcomes that are largely unpredictable because dissection may commence too far from the DL (i.e., above the ARL) and cause constipation, or the ATZ may be injured if dissection is commenced too close to the DL (i.e., below the ARL) and cause fecal incontinence.

TAPT has benefitted from the incorporation of minimally invasive surgical techniques. In particular, laparoscopy-assisted TAPT (L-TAPT) has significant advantages; the presence of ganglion cells can be verified in the proximal bowel segment using laparoscopy-assisted colon suction biopsy, torsion during pull-through can be prevented, marginal arteries are left intact because laparoscopy enables surgery to progress without physically disrupting them ensuring full preservation of blood supply to the distal end of the pull-through colon, and tension on the vascular arcade of the pull-through colon can be prevented.

From experience, using L-TAPT with the ARL as the landmark for transanal dissection will result in favorable predictable POBF without risk for inadequate pull-through of aganglionic bowel.