Oesophageal Anatomy Flashcards
What marks the start of the oesophagus?
Base of the pharynx at C6
What marks the end of the oesophagus?
Cardia, T11
In which direction does the oesophagus deviate to accommodate the trachea?
Left of the trachea
At the level of the carina, what structure does it deviate to the right for?
The arch of the aorta
In which direction does it move to accommadate for the left mainstem bronchus?
Left
Which side does the oesophagus enter the diaphragm?
Left
What are the 4 oesophageal segments?
Pharyngeal, cervical, thoracic, abdominal
What creates the Killian triangle?
Transition between the oblique fibres of the thyropharyngeus and the horizontal fibres of the cricopharyngeus creates a point of potential weakness (site of zenker diverticulum)
How does the oesophageal muscle change as it passes distally?
Proximal 1/3 is striated and distal 2/3 is smooth.
Made from 2 muscle layers, inner circular and outer longitudinal
What are the 3 distinct areas of narrowing of the oesophagus?
1) Cricopharyngeus (14mm)
2) Bronchoaortic constriction (left main bronchus and aorta abut oesophagus). T4, 15-17mm
3) Diaphragmatic constriction (16-19mm)
Where does the oesophagus receive its blood supply from?
(Cricopharyngeus supplied by superior thyroid)
1) Cervical - inferior thyroid artery (thyrocervical trunk onleft and subclavian on right)
2) Thoracic - from 4-6 branches from aorta as well as from branches from R and L bronchial arteries
3) Abdominal - from inferior phrenic and left gastric artery.
What veins are involved in the venous drainage of the oesophagus?
Parallel to arterial supply
What is the lymphatic drainage of the oesophagus?
The upper 2/3s, the lymphatic flow is upward
The distal 1/3, the flow is downward
