Anatomy

Question 0

Describe the functions of the esophageal and cardiac sphincters.

Answer 0

Upper esophageal sphincter prevents air from entering the esophagus. Lower sphincter/cardiac sphincter prevents stomach contents from entering the esophagus.

Question 1

Describe the anatomy of the esophagus.

Answer 1

Posterior to the trachea.
Extends from C5-6 to T11
1/2in diameter at the pharynx
1in diameter at the stomach
Outer longitudinal fibers
Inner circular fibers

Question 2

Type of fibers

Answer 2

Upper 1 inch is striated fibers
Next 3 inches are mixed
Lower 6 inches are unstriated

Question 3

Divisions

Answer 3

Pharyngoesophageal (PE) segment: area where tubes blend together.
Upper esophageal sphincter (UES): upper one inch
Thoracic segment ( upper to lower sphincter): middle 8 inches
Lower esophageal sphincter ( cardiac sphincter): lower 1 inch; called that because of location near the heart.

Question 4

Nerve supply

Answer 4

Super laryngeal nerve, loses neural intervention during surgery.
Recurrent laryngeal nerves, not respected because of location.
Part of the Vagus nerve.

Question 5

Vagus nerve

Answer 5

Mostly sensory, 10% motor
Inner ages many parts in the neck
Supplies motor to cricopharyngeus muscle.
Recurrent branches below the larynx and comes back up supplying the intrinsic muscles - cricothyroid is motor to the larynx, cut when larynx is removed but inner action to the esophagus is preserved.

Question 6

Pharyngeal branch

Answer 6

Lesion in the brainstem may lead to hypernasality, paralyzed vocal folds, dysphagia, etc.