Esophagus

Last revised by Dr Calum Worsley on 05 May 2022

The esophagus (plural: esophagi or esophaguses) is a muscular tube that conveys food and fluids from the pharynx to the stomach. It forms part of the upper gastrointestinal tract.

The esophagus is 23-37 cm long with a diameter of 1-2 cm and is divided into three parts:

The cervical esophagus begins at the upper esophageal sphincter, which is formed by the cricopharyngeus muscle 6.

The esophagus then descends to the left of the midline through the neck and superior mediastinum, returning to the midline at T5, before coursing to the left of the midline once more, in the posterior mediastinum. The distal thoracic esophagus then curves anteriorly to pass through the diaphragm into the abdominal cavity. 

The lower esophageal sphincter, a specialized region of the circular muscle of the distal esophagus, manifests itself radiographically as the phrenic ampulla (a.k.a. esophageal vestibule), a 2-4 cm long dilatation between the A-ring and B-ring 6.

There are three normal esophageal constrictions that should not be confused for pathological constrictions:

  • cervical constriction: due to cricoid cartilage at the level of C5/6
  • thoracic constriction: due to aortic arch at the level of T4/5
  • abdominal constriction: at esophageal hiatus at T10/11

Follows arterial supply:

  • upper third: deep cervical lymph nodes
  • middle third: posterior mediastinal lymph nodes
  • lower third: left gastric and celiac group lymph nodes

The esophagus is made up of five layers, noting there is no serosal layer. From outer to inner, these are:

  • adventitia
  • muscularis propria
    • outer longitudinal muscularis propria
    • inner circular muscularis propria (in the upper one-third of the esophagus this layer is composed of striated (voluntary) muscle while the lower two-thirds is smooth muscle)
  • submucosa
  • mucosa
    • stratified squamous epithelium that abruptly changes to columnar epithelium in the lower esophagus
  • modified barium swallow used to evaluate pharyngeal motility during swallowing, the procedure utilizes barium of varying consistencies given by mouth with video recording of swallowing
  • barium swallow is the main radiological method of assessing the esophagus. Double contrast esophagogram using CO2 gas-forming crystals and barium contrast are used to distend the esophagus and coat the mucosa.

Endoscopic ultrasonography is used for evaluation of the depth of the esophageal tumor.

CT

  • 80% will contain gas allowing for appreciation of wall if there is enough surrounding mediastinal fat
  • if collapsed will appear as round or ovoid
  • T1: isointense to muscle
  • T2: hyperintense to muscle

Useful for the staging of esophageal cancer.

ADVERTISEMENT: Supporters see fewer/no ads

Cases and figures

  • Figure 1: esophageal landmarks
    Drag here to reorder.
  • Updating… Please wait.

     Unable to process the form. Check for errors and try again.

     Thank you for updating your details.