Introduction: A modified pull-through (PT) distinguished by complete full-thickness removal of the posterior rectal cuff, initially developed as an open procedure in 1980, has been performed with laparoscopic assistance since 1997. Postoperative bowel dysfunction improved when the anatomic landmark for PT surgery was revised from the dentate line (DL) to the anorectal (or Herrmann's) line (ARL) in 2007. A 40-year (1980-2019) review of 153 consecutive rectal/rectosigmoid type Hirschsprung's disease (HD) patients is presented. Methods: Data for postoperative bowel dysfunction and Hirschsprung-associated enterocolitis (HAEC) classified according to the American Pediatric Surgical Association (APSA) scale were obtained retrospectively. Results: PT was open (n = 43) and laparoscopic (n = 110). Dissection was DL (n = 57) and ARL (n = 96). Over 40 years, 5/153 patients (3.3%) had postoperative obstructive symptoms (POS), and 10/153 patients (6.5%) had 13 episodes of postoperative HAEC; APSA grades were: I (n = 4); II (n = 8); and III: (n = 1) presenting with explosive diarrhea (10/13; 76.9%), fever (10/13; 76.9%), abdominal distension (9/13; 69.2%), or bloody stools/shock (1/13 with grade III; 7.7%). The grade III case had histologically-proven transitional zone PT. Postoperative HAEC developed in 3/5 (60.0%) POS+ patients and 7/148 (4.7%) POS- patients (P = .002). Symptom duration and treatment were not correlated with APSA grades. Conclusions: Complete full-thickness posterior rectal cuff excision and using the ARL reduced postoperative HAEC significantly in this series. Despite being anatomically distinct, the DL is inadequate as a precise landmark for PT surgery because it lacks functional relevance. The APSA scale could benefit from timely review to improve its clinical and prognostic value.
Keywords: Herrmann's line; Hirschsprung associated enterocolitis; Hirschsprung's disease; anorectal line; dentate line; obstructive symptoms.