Features of endoscopic anatomy of transition zones of the gastrointestinal tract and their clinical significance

Objective. To identify the features of endoscopic anatomy of the esophagogastric, gastroduodenal and ileocecal junctions to improve diagnostics and treatment of diseases of these sections. Materials, methods. The study material was: • middle-aged and elderly men and women without diseases of the esophagogastric (EGJ), gastroduodenal (GDP), ileocecal (ICP) junctions in 110, 208 and 97 people, respectively; • macropreparations of the EGJ from 70 people who died from diseases not associated with pathology of the gastrointestinal tract (GIT); • capsule endoscopy in 104 patients. Methods: clinical, endoscopic, radiological, anatomical. Endoscopic methods: traditional flexible endoscopy with Olympus video endoscopes (Japan) and capsule endoscopy with PillCam Colon2 capsule (Israel). Results. The combination of methods used in the study of 3 transition zones of the gastrointestinal tract allowed us to identify: • the presence of columnar epithelium in the esophagus, which is a variant of the norm and facilitates the diagnosis of Barrett’s esophagus; • creation of a duplicate in the esophagus from flat and underlying columnar epithelium when they are connected, which requires a step biopsy or clarifying endoscopic methods to exclude precancerous changes in the mucous membrane or adenocarcinoma; • transition of the gastric mucosa through the pylorus into the bulb of the duodenum, which dictates the need to exclude preneoplastic changes in these areas; • circular fold around the opening of the bulbous side of the pylorus, which may be one of the antireflux mechanisms of the GDP; • feature of the location of the appendix opening, the predominant shape and number of folds of the dome of the cecum, the shape of the Bauhinia valve. Conclusion. The identified features of the transitional zones of the gastrointestinal tract contribute to the improvement of the diagnosis and treatment of their diseases. Capsule endoscopy is a method that allows studying the endoscopic anatomy of transitional zones and examining hard-to-reach zones of the gastrointestinal tract. With the help of capsule endoscopy, a circular fold around the opening of the bulbous side of the pylorus was discovered for the first time, which may be one of the antireflux mechanisms of the gastroduodenal junction.