[Modification of Svenson's biopsy of rectal wall in diagnosis of malformations of intramural nervous system in adults].

Thirty-five autopsied specimens of rectum's distal part and anal canal part were studied. It was revealed that length of physiological hypogangliosis zone ranged from 7.5 to 50.0 mm (mean 24.4+/-10.9 mm). With regard to this wide range the modification of transanal Svenson's biopsy of rectal wall was proposed for diagnosis of malformations of intramural nervous system of the colon. The method was used in 21 patients with megacolon. The results demonstrate accuracy and safety of this diagnostic method.