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Does an anatomical sphincter exist in the distal esophagus?
Nihal Apaydin1, Aysun Uz, Alaittin Elhan
1Department of Anatomy, Ankara University Medical School, 06100 Sihhiye, Ankara, Turkey. nihalapaydin03@yahoo.com
Surgical and Radiologic Anatomy : SRA
|November 9, 2007
Summary
This study investigated the gastro-esophageal region in cadavers, revealing a distinct muscular thickening in the distal esophagus. These findings suggest the presence of an internal esophageal sphincter, warranting further physiological research.
Area of Science:
- Anatomy
- Gastroenterology
- Morphology
Background:
- The existence of a lower esophageal sphincter (LES) remains a subject of scientific discussion.
- Previous research has not definitively established the anatomical basis of the LES.
Purpose of the Study:
- To anatomically investigate the gastro-esophageal junction.
- To determine the presence or absence of a distinct muscular structure in the distal esophagus.
Main Methods:
- Dissection of the distal esophagus in 12 fixed and 2 fresh human cadavers.
- Microscopic examination of the gastro-esophageal region.
- Measurement of muscle layer thickness and length.
Main Results:
- A consistent muscular thickening was observed in the distal esophagus of all specimens.
- The mean length of this muscular thickening was 3.1 cm, with the thickest portion measuring 5.4 mm.
- The esophageal wall superior to this thickening averaged 2.7 mm.
Conclusions:
- The morphological findings strongly indicate the presence of an internal esophageal sphincter.
- Further physiological studies are recommended to confirm these anatomical observations.
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