Background: The transanal one-stage endorectal pull-thro-ugh operation for Hirschsprung’s disease is relatively new and makes assessment of the functional outcome and colo-nic motility difficult. The aim of this study was to evaluate the stooling patterns and colonic motility after a one-stage transanal pull-through operation for Hirschsprung’s disease in children. Methods: Twenty-two children who underwent a one-stage transanal pull-through operation for Hirschspru-ng’s disease were followed up for at least 6 months. The children (17 boys and 5 girls) were from 12 months to 13 years of age (mean age, 4 years). All patients had an aga-nglionic segment confined to the rectosigmoid area (confir-med by preoperative barium enema and postoperative histology). Clinical outcome was assessed by interviews and questionnaires, and children were divided into symptomatic and nonsymptomatic groups. Contrast barium enema and defecography and determination of total and segmental colonic transit time (using radio-opaque markers) were performed on all 22 children. Results: The stooling patterns were considered satisfactory in 17 children. Of all the children, the mean stool times were 1 to 2 per day and only 2 were 8 to 10 per day; postoperative soiling was found in 4, constipation was observed in 2, and Hirschsprung-asso-ciated enterocolitis in 1. There was no incontinence, cuff infection, anastomotic leak, or mortality noted. Barium enema showed that the dilated and spastic colonic segment disappeared in all 22 children. The dilated sigmoid loops decreased in 17 (2 symptomatic, 15 nonsymptomatic) and disappeared in 5 (4 symptomatic, 1 nonsymptomatic). There was a significant difference between the decreasing and disappearing loop group in regard to stooling disorders (P < .05). Postoperative defecography showed that the anorectal angle of all children was open, fixed, and significantly larger than that of the preoperative and control groups (123.3° ± 15.1° vs 84.7° ± 8.3° vs 79.0° ± 11.6° , P < .01) and larger in
