1. Congenital aganglionic megacolon should be considered even in adult megacolon.

2. It could be shown that neurogenic megacolon in adults is not only caused by aganglionosis but also by non-aganglionic innervation disorders.

3. Etiology, course and treatment of some anorectal diseases (rectal prolapse, haemorrhoids, anal fissure, megacolon congenitum) can be deduced from the normal and pathological anatomy.

4. In 144 pull-through-operations performed for anorectal-atresia, following complications were observed: pneumonia 11%, sepsis 8.3%, peritonitis 5%, bowel obstruction 5%, osteomyelitis 1%, retraction of the pulled-through colon 4%, anal stenosis 16%, secondary megacolon 9%, fistula relapse 8%, mucosal prolapse 4%. Recto-urethral, recto-vesical- and recto-vaginal fistula relapses are managed by interposition of the gracile muscle.