Esophagus Anatomy

Question 1

Name the layers of the esophagus:

Answer 1

Mucosa and muscularis propria (the esophagus has no serosa)

Question 2

What is the arterial blood supply to the cervical esophagus?

Answer 2

Inferior thyroid arteries (branch of thyrocervical trunk on the left and subclavian artery on the right)

Question 3

What is the arterial supply to the thoracic esophagus?

Answer 3

Direct blood supply from 4 to 6 esophageal arteries off of the aorta; esophageal branches off of right (R) and left (L) bronchial arteries; supplemented by descending branches off the inferior thyroid arteries, intercostal arteries, and ascending branches of the paired inferior phrenic arteries

Question 4

What is the arterial blood supply to the abdominal esophagus?

Answer 4

Left gastric artery and the paired inferior phrenic arteries

Question 5

Describe the venous drainage for the cervical esophagus:

Answer 5

The submucosal venous plexus drains into the inferior thyroid veins (tributaries of L subclavian vein and R brachiocephalic vein)

Question 6

Describe the venous drainage for the thoracic esophagus:

Answer 6

The submucosal venous plexus of the thoracic esophagus joins with the more superficial esophageal venous plexus and the venae comitantes that surround the esophagus at this level. This plexus then drains into the azygos veins on the right and the hemiazygos veins on the left.

Question 7

Describe the venous drainage of the abdominal esophagus:

Answer 7

Drains into both the systemic and portal venous systems through the L and R phrenic veins and the L gastric (coronary) vein and short gastric veins

Question 8

In what direction is the lymphatic flow in the upper two-thirds of the esophagus?

Answer 8

Cephalad

Question 9

In what direction is the lymphatic flow in the distal third of the esophagus?

Answer 9

Caudad

Question 10

Describe the sympathetic innervation of the esophagus:

Answer 10

Cervical esophagus receives branches from the cervical sympathetic trunk (from superior ganglion in the neck); the thoracic esophagus receives branches from the thoracic sympathetic trunk (from the stellate ganglion), which form an esophageal plexus that envelops the thoracic esophagus anteriorly and posteriorly; the distal thoracic esophagus receives innervation from the greater and lesser splanchnic nerves

Question 11

The parasympathetic fibers to the esophagus arise from which cranial nerve?

Answer 11

Vagus nerve

Question 12

The esophagus is composed of which 2 concentric muscle bundles?

Answer 12

Inner circular and outer longitudinal

Question 13

What kind of muscle composes the upper one-third of the esophagus?

Answer 13

Striated muscle (voluntary)

Question 14

What kind of muscle composes the lower two-thirds of the esophagus?

Answer 14

Smooth muscle (involuntary)

Question 15

At what vertebral level does the esophagus enter the diaphragm through the esophageal hiatus?

Answer 15

T11

Question 16

What are the areas of anatomic narrowing of the esophagus?

Answer 16

Cricopharyngeus muscle; compression by the left mainstem bronchus and aortic arch; diaphragm

Question 17

What is the Z-line?

Answer 17

The transition of the distal 1 to 2 cm of esophageal mucosa to cardiac mucosa/junctional columnar epithelium

Question 18

Identification of gastroesophageal junction (external):

Answer 18

The collar of Helvetius (loop of Willis) and the gastroesophageal fat pad

Question 19

Identification of gastroesophageal junction (internal):

Answer 19

The squamocolumnar epithelial junction (Z-line), provided the patient does not have Barrett esophagus

The transition from the smooth esophageal lining to the rugal folds of the stomach