It is a narrow muscular tube measuring 25 cm longconnecting pharynx with stomach. It begins as a continuation oflaryngopharynx at the level oflower border of cricoid cartilage at the level of C6 vertebrae and passes through the diaphragm at the level of T10 through oesophagealhiatus of diaphragm. It ends at T10 level by opening into cardiac orifice of stomach. Oesophagus does not have straight courserather it presents anteroposterior curvatures. It is lined by stratified squamous non keratinized epithelium.
Esophagus is divided into three parts (i) Cervical part (4 cms), (ii) Thoracic part (20 cms), and (iii) abdominal part (1-2cm).
Blood supply and lymphatic drainage
Arterial supply of cervical part is by inferior thyroid artery,thoracic part by esophageal branches of descending thoracic aorta and branchial arteries, and abdominal part by left gastric artery and left inferior phrenic artery.
Venous drainage of cervical part is through brachiocephalic veins, thoracic part by azygous vein, and abdominal part by left gastric vein.
Lymphatic drainage of cervical part is by deep cervical nodes, thoracic part is by posterior mediastinal nodes and abdominal part is by left gastric nodes.
Constrictions of esophagus
Oesophagus shows four constrictions -
At its beginning, at C6vertebra:-15 cm (6 inches) from incisor.
At the level of T3 vertebra where it is crossed by arch of aorta: - 22.5 cm (9 inches) from incisor.
At the level ofT6 vertebra where it is crossed by left principal bronchus: - 27.5 cm (11 inches) from incisor.
At the level of T 10 vertebra, its passage through esophageal hiatus of diaphragm (lower esophagealsphincter: -37.5-40 cm (15-16 inches) from incisor.
The narrowest part oftheoesophagus is its commencement at the cricopharyngealsphincter.
Test Your Skills
Test Your Skills Now!
This is only a practice test, it is designed to help you revise your concepts
The test contains questions, only 1 option is correct for each question
This is a timed test.
After you have finished the test, press on the 'Finish Test' button to know your score and get the correct answers