Frozen Section Doughnuts Obtained with a 5 mm Stapling Device Improve Outcomes in Laparoscopic Endorectal Pull-Throughs for Hirschsprung's Disease.

Background: A primary pull-through for Hirschsprung's disease (HD) requires confirmation of normal ganglionic bowel by intraoperative biopsies to determine the level of resection. Despite this, aganglionic bowel that is not fully resected (so-called "transition zone pull-throughs") is reported in 15%-19% of patients. We hypothesize that this may result from insufficient biopsies sent for intraoperative diagnosis. Methods: A new biopsy protocol has been developed in our institution for patients undergoing a laparoscopic-assisted endorectal pull-through for HD. Laparoscopic seromuscular biopsies are taken as per standard practice and are reported intraoperatively to identify the most distal site of ganglionic bowel. A 5 mm laparoscopic stapling device is used to divide the bowel at the proposed proximal resection margin and 2 cm distally. If there is any evidence of abnormality in the first doughnut, a second, more proximal doughnut is taken. Results: Between 2015 and 2020, 21 patients underwent a primary laparoscopic endorectal pull-through for HD using the doughnut biopsy protocol. Sixteen patients were male. The mean patient age at the time of surgery was 3 months (range 1-6 months), and the mean weight at the time of surgery was 6.5 kg (range 4.1-8.54 kg). In all 21 cases, initial laparoscopic biopsies were reported showing normal ganglionic bowel; in two cases (10%), the laparoscopic doughnut influenced the proximal resection margin. In both cases, aganglionic tissue was identified intraoperatively in the doughnuts, and a second, more proximal doughnut was sent. No patients had transition zone resections on final histology (mean clear margin 45.55 mm, range 11-72 mm). Conclusions: In conclusion, intraoperative frozen sections taken from doughnuts of bowel retrieved using 5 mm laparoscopic stapling devices are safe and have resulted in a 0% rate of transition zone pull-throughs while reducing the potential of spillage of enteric contents. We would recommend this protocol for all patients undergoing primary endorectal pull-throughs.