Oesophagus Flashcards
what is the oesophagus?
a fibromuscular tube that transports for from the pharynx to the stomach
an inferior continuation of the laryngopharynx
where does the oesophagus start?
cricopharynxgeus muscle
vertebrae C6
where does the oesophagus end?
when it enters the cardia of the stomach
where does the oesophagus transverse the diaphragm?
T10, the oesophageal hiatus
at what vertebral level does the oesophagus enter the stomach?
T11
what is the course of travel of the oesophagus?
travels posterior to the trachea
posterior to the heart
through the diaphragm
terminates by entering cardia of stomach at T11
where is the anatomical upper sphincter of the oesophagus?
cricopharyngeus
what makes the physiological lower sphincter of the oesophagus?
abrupt change in mucosa at the gastro-oesophageal junction
Z line
what creates the lower sphincter effect?
contraction of the diaphragm
intrabdominal pressure being slightly higher than epigastric pressure
the acute angle that the oesophagus enters the cardia
what does the physiological lower sphincter help to reduce?
reflux
how can hiatus hernias lead to reflux?
they can reduce the effectiveness of the physiological sphincter
what are the constrictions if the oesophagus and what structures are they caused by?
cervical - cricopharynxgeus muscle
thoracic - arch of aorta and left main bronchus
diaphragmatic - result of passing through diaphragm, lower oesophageal sphincter
where is the oesophageal plexus?
it runs of the surface to supply the smooth muscle within its walls
what does the oesophageal plexus contain?
parasympathetic nerve fibres (vagal)
sympathetic nerve fibres
influence enteric nervous system - speed up or slow down peristalsis
what is peristalsis?
the involuntary contraction and relaxation of circular and longitudinal muscles in the digestive tract
