Oesophagus Flashcards
where does the oesophagus begin
C6, continuous superiorly with the laryngopharynx
describe the route that the oesophagus follows
C6, descends into superior mediastinum, between the trachea and vertebral bodies of T1 to T4
enters abdomen and terminates at cardiac orifice of the stomach
how does the oesophagus enter the abdomen
via the oesophageal hiatus, which is an opening in the right crus of the diaphragm
where does the oesophagus terminate
joining the cardiac orifice of the stomach at level T11
what are the layers of the oesophagus
adventitia, muscle layer, submucosa, and mucosa
what is the adventitia
outer layer of connective tissue
is the entire oesophagus covered in adventitia
no
which portion of the stomach is not covered with adventitia, and what is it covered with instead
the intraperitoneal portion, and it is covered with serosa
what are the muscle layers of the oesophagus
external longitudinal and inner circular
what is mucosa
non keratinised stratified squamous epithelium
how is food transported down the oesophagus
peristalsis
which muscle produces the upper oesophageal sphincter
cricopharyngeus muscle
why is the upper oesophageal constricted if a person is not actively swallowing food
to prevent air from entering into the oesophagus
at what angle does the lower oesophageal sphincter enter the stomach
acute
why are there promient mucosal folds on the lower oesophageal sphincter
occlude the lumen
how can the oesophagus be divided when considering its vasculature
thoracic and abdominal components
describe the vasculature of the abdominal portion of the oesophagus
left gastric artery, which is a branch of the coeliac trunk.
left inferior phrenic artery.
venous drainage is mixed, as it is partly portal circulation via the left gastic vein and partly systemic circulation via the azygous vein
what is formed at the connection of the portal and systemic venous systems
porto systemic anastomosis
what does the thoracic part of the oesophagus receive its blood supply from
branches of the thoracic aorta and inferior thyroid artery
describe the venous drainage of the thoracic portion of the oesophagus
thyroid vein and azygous veins
describe the innervation of oesophagus
the oesophageal plexus
what forms the oesophageal plexus
a combination of parasympathetic vagal runks and sympathetic fibres from the cervical and thoracic sympathetic trunks
what are the different fibres that run in the vagal trunks
fibres supplying the lower oesophageal sphincter and smooth muscle of the lower oesophagus
