Esophagus Flashcards
(127 cards)
Three areas of esophageal narrowing are?
cricopharyngeus muscle
aortic notch
GEJ
Why are the three areas of esophageal narrowing important?
these are where foreign objects that are swallowed tend to be lodged
swallowed corrosive liquids also tend to cause damage here because of slower passage of material here
Opening of esophagus and ending of pharynx is collared around what muscle?
cricopharyngeus mc
Where do the recurrent laryngeal nerves lie in relation to the esophagus?
lie in the right and left grooves between trachea and esophagus
Length of esophagus?
cervical 5 cm
thoracic is 20 cm
abdominal 2cm
Muscles of the esophagus?
outer longitudinal layer
inner circular layer
Muscles of upper esophagus vs lower esophagus?
upper 1/3–> striated
lower 2/3—> smooth (most esophageal motility d/o involve the smooth part of esophagus)
Blood supply of esophagus?
cervical part—> from inferior thyroid A (from subclavian)
thoracic part—> bronchial arteries (1 right sided bronchial artery and 2 left sided most commonly); also get 2 esophageal branches from aorta
abdominal part–> ascending branch of left gastric A and inferior phrenic a
Right and left recurrent laryngeal nerves turn where?
R–> underneath right subclavian A
L–> underneath aortic arch
Venous drainage of esophagus?
cervical–> inferior thyroid vein
thoracic–> azygous, hemi-azygous, bronchial veins
abdominal–> coronary veins
PSNS innvervation of the esophagus?
vagus n
Swallowing is what type of act?
reflexive
What happens when we swallow food?
tongue moves bolus in posterior oropharynx
soft palate is elevated
hyoid bone elevated
epiglottis covers larynx
Describe the course of the esophagus?
cervical esophagus begins as midline structure; then deviates to the left of trachea as passes thru thoracic inlet
at level of carina it deviates to the right to accomadate aortic arch
then deviates to left as it enters diaphragm at T11
At what level does esophagus enter diaphragm
T11
What’s Killian’s triangle?
point of weakness in cervical esophagus
transition point between thyropharyngeus and cricopharyngeus muscle
What m. is responsible for generating the high pressure in the UES?
circopharyngeus
How do we distinguish esophagus from other alimentary organs?
lacks a serosa
What’s a Z line?
point where squamous tissue of esophagus transitions to columnar epithelium of stomach
Musculature of the esophagus?
has outer longitudinal fibers
has inner circular m fibers
upper 1/3–> striated skeletal muscle
lower 2/3–> smooth muscle fibers
How can we identify the GEJ?
squamo-columnar Z line junction helps identify it
transition from smooth esophageal lining to ruggael folds of stomach also helps identify it
the gastro-esophageal fat pad also helps delineate the GEJ
Cervical esophagus supplied by what artery?
inferior thyroid artery–> from thyrocervical trunk–> from L/R subclavians
What’s blood supply of circopharyngeus m, which marks the upper portion of the cervical esophagus?
superior thyroid artery
Blood supply of thoracic esophagus?
4-6 branches directly off the aorta
esophageal branches off of R/L bronchial arteries