Oesophagus

The oesophagus is a narrow tube that connects the mouth to the stomach, allowing food to reach there. It has stratified, non-keratinised squamous epithelium.

Tract
The oesophagus descends from the mouth into the diaphragm; through the oesophageal hiatus at the T10 level. It has a midline position as it moves down the thorax. Nearing the diaphragm, it moves to be left and anterior to the thoracic Aorta.

Compressions

 * 1) Junction of the pharynx and the oesophagus
 * 2) Superior mediastinum - arch of Aorta
 * 3) Posterior mediastinum - left main bronchus
 * 4) Posterior mediastinum - compressed hiatus

Innervation

 * Vagus nerve and sympathetic trunk
 * Striated muscle by bronchial branch of vagus nerve
 * Smooth muscle by parasympathetic fibres

Oesophageal Plexus
Anterior vagal trunk comes from the left vagus nerve; the posterior vagal trunk comes from the right vagus nerve.

Divisions
The oesophagus is 23-27cm long and 1-2cm in diameter. It is divided into three parts: cervical, thoracic and abdominal
 * Cervical - anterior to vertebral column: C6 to T1
 * Thoracic - superior and posterior mediastinum: T1 to oesophageal hiatus
 * Abdominal - from diaphragm to cardiac orifice

Oesophageal Varices
Veins drain portal and systemic blood. In portal hypertension, there is no blood flow into portal vein. This causes reverse flow through oesophageal tributaries, dilating the sub-mucosal veins in the oesophagus. This may lead to cirrhosis or oesophageal cancer.

Syntopy

 * Left - Aorta
 * Anterior - heart and pericardium
 * Posterior - vertebral column
 * Lateral and medial - lungs