Anatomy of the Esophagus

Esophagus

Structure

• Muscular tube, approximately 25-30 cm long and 2-3 cm in diameter
• Located behind the trachea and in front of the spine
• Composed of four layers: mucosa, submucosa, muscularis, and adventitia

Functions

• Food transportation from the pharynx to the stomach
• Peristalsis: muscular contractions that propel food through the esophagus
• Relaxation of the lower esophageal sphincter (LES) allows food to enter the stomach

Layers

• Mucosa: innermost layer, lined with stratified squamous epithelium and mucous glands
• Submucosa: layer of loose connective tissue with blood vessels and nerve fibers
• Muscularis: layer of smooth muscle, responsible for peristalsis
• Adventitia: outermost layer, composed of loose connective tissue and fibroelastic tissue

Important Features

• Upper esophageal sphincter (UES): involuntary muscle that separates the esophagus from the pharynx
• Lower esophageal sphincter (LES): involuntary muscle that separates the esophagus from the stomach
• Esophageal glands: produce mucus to lubricate food and facilitate swallowing

Esophagus

Structure

• The esophagus is a muscular tube, approximately 25-30 cm long and 2-3 cm in diameter
• It is located behind the trachea and in front of the spine
• The esophagus is composed of four layers: mucosa, submucosa, muscularis, and adventitia

Functions

• The esophagus is responsible for transporting food from the pharynx to the stomach
• It achieves this through peristalsis, a series of muscular contractions that propel food through the esophagus
• The lower esophageal sphincter (LES) relaxes to allow food to enter the stomach

Layers

• The mucosa is the innermost layer, lined with stratified squamous epithelium and containing mucous glands
• The submucosa is a layer of loose connective tissue with blood vessels and nerve fibers
• The muscularis is a layer of smooth muscle responsible for peristalsis
• The adventitia is the outermost layer, composed of loose connective tissue and fibroelastic tissue

Important Features

• The upper esophageal sphincter (UES) is an involuntary muscle that separates the esophagus from the pharynx
• The lower esophageal sphincter (LES) is an involuntary muscle that separates the esophagus from the stomach
• Esophageal glands produce mucus to lubricate food and facilitate swallowing