Oesophagus Flashcards
What is the oesophagus
A muscular tube that runs from the pharynx to the stomach
Where does the oesophagus pass through
The pharynx, neck, thorax, abdomen and abdomen
What epithelium is found in the oesophagus
Stratified squamous non-keratinised epithelium
What are the muscle layers of the oesophagus
Muscular is mucosae
Inside circular muscle and outside longitudinal muscle
What muscle types are found in the oesophsgus
Upper part - skeletal
Middle part - mixed
Lower part - smooth
What can acid reflux cause
Metaplasia - change of tissue nature
Dysplasia - precancerous
Gastro-oesophageal reflux disease
What is the oesophageal hiatus
The opening where the oesophagus penetrates the diaphragm
What are sphincters
Muscles that surround tubes and serve as valves
What are the sphincters of the oesophagus
Upper oesophageal sphincter and lower oesophageal sphincter
Describe the upper oesophageal sphincter
Continuous with the inferior pharyngeal constrictor
Describe the lower oesophageal sphincter
Relaxes to let food pass into the stomach
Contracts to prevent acid reflux
What does the lamina propria in the mucosa contain
Mucus secreting gland as well as nerves and muscles
What is the most superficial layer of the oesophagus
Adventitia
What is the gastro-oesophageal junction
Abrupt transition from stratified squamous epithelium of the oesophagus to the simple columnar epithelium of the stomach
What are the roles of swallowing
Transports food to stomach
Prevents food from entering the airway
What are the stages of swallowing
Oral phase
Pharyngeal phase
Oesophageal phase
What is dysphagia
Difficulty swallowing
What are causes of dysphagia
Stroke
Genetic conditions
Neuromuscular disease or obstructions
What is trachea-oesophageal fistula
The trachea and oesophagus become connected resulting in repeated vomiting
What is zener’s diverticulum
Occurs in the oesophagus as a pouch posterior to the upper oesophageal sphincter
How can dysphagia/alchasia be treated
Ballon dilation or treatment of underlying pathology
What is the mucosa comprised of
Epithelium, lamina propria and muscular is mucosae
What is the function of the muscularis mucosae
It is a thin layer of smooth muscle tissue and provides local movement of the mucosa
What is present in the submucosa
Connective tissue that is thicker than the mucosal layer Numerous small glands Blood vessels Lymphatics Parasympathetic nerves
