Long-term functional results, anal endosonography (AES), and anal canal manometry were recorded in 48 patients aged 10 to 24 years (median 18) operated upon with the Duhamel technique for Hirschsprung's disease; 60.4% had perfect fecal control, 31.3% occasional staining and/or gas incontinence, and 8.3% constant fecal soiling, and 10.4% complained of constipation. Compared to normals, the patients had significantly reduced anal canal resting and squeeze pressures. AES visualized scar tissue in both the internal and external anal sphincter.