Anatomy of the oesophagus

The oesophagus is a conduit between the pharynx and stomach. It may be described as consisting of cervical, thoracic and abdominal parts. The oesophagus is lined throughout by stratified squamous epithelium. The blood supply of the oesophagus is derived from branches of the inferior thyroid artery, multiple small branches arising directly from the thoracic aorta and from oesophageal branches of the left gastric artery. At the lower end of the oesophagus, within the mucosa and submucosa, is an important porta-systemic venous anastomosis between oesophageal tributaries of the left gastric vein and oesophageal tributaries of the azygos vein. This anastomosis assumes great clinical significance in portal hypertension. Both at its proximal and distal ends, the oesophagus possesses a sophisticated sphincter mechanism. The proximal sphincter acts to regulate and control entry of food and liquid into the oesophagus. At the distal end, there is no demonstrable anatomical sphincter. Nevertheless, a number of factors acting in concert provide a very efficient ‘physiological’ sphincter mechanism that prevents reflux of acidic gastric contents into the oesophagus. The oesophagus is susceptible to a number of pathological conditions, both congenital and acquired, which may require surgical management. These include congenital oesophageal atresia, functional disorders such as achalasia cardia and hiatus hernia, corrosive strictures, traumatic oesophageal perforation and oesophageal cancer.This article describes, in detail, those aspects of the topographical anatomy of the oesophagus which are of particular relevance to clinical diagnosis and surgical management.