Thoracic Oesophagus Research Paper

The thoracic oesophagus is situated a little to the left in the superior mediastinum between the trachea and the vertebral column. It passes behind and to the right of the aortic arch to descend in the posterior mediastinum along the right side of the descending thoracic aorta. Below, as it inclines left, it crosses anterior to the aorta and enters the abdomen through the diaphragm at the level of the tenth thoracic vertebra. From above downwards, the trachea, right pulmonary artery, left main bronchus, pericardium (separating it from the left atrium) and the diaphragm are anterior. The vertebral column, longus colli, right posterior intercostal arteries, thoracic duct, azygos vein and the terminal parts of the hemiazygos and accessory hemiazygos

It lies to the left of the midline and enters the abdomen through the oesophageal aperture (formed by the two diaphragmatic crura) opposite the level of the tenth thoracic vertebra. It runs obliquely to the left and slightly posteriorly, and ends at the gastro-oesophageal junction/cardiac orifice of the stomach. The abdominal oesophagus lies posterior to the left lobe of the liver, which it grooves slightly, anterior to the left crus, the left inferior phrenic vessels and the left greater splanchnic nerve; its surface is covered in a thin layer of connective tissue and visceral peritoneum which contains the anterior and posterior vagi as well as the oesophageal branches of the left gastric vessels. The anterior vagus may be single or composed of multiple trunks, and is closely related to the outer fibres of the longitudinal muscle coat of the oesophagus. The posterior vagus is usually a single trunk and is less closely applied to the oesophageal muscle within the loose connective tissue, which makes its identification during surgery somewhat easier. The abdominal oesophagus is effectively tethered to the diaphragm by connective tissue; the phreno-oesophageal ligament. This is formed of two thickened bands of elastin-rich connective tissue; the inferior phreno-oesophageal ligament is effectively an extension of the transversalis fascia extending

At the distal end of the esophagus, there is a normally closed, 3 cm-4 cm long high-pressure zone that functions as an anti-reflux barrier separating the negative intrathoracic pressure in the esophagus from the positive intra-abdominal pressure in the stomach. This high-pressure zone was first described manometrically by Fyke and colleagues in 1956, but has been the subject of much debate, because of the complex anatomy in this region. We now know this high-pressure zone has 2