Course Of Vagus And Phrenic Nerve Through The Thorax

Question 1

What does the right vagus nerve form in the thorax

Answer 1

The posterior vagal trunk

Question 2

What does the left vagus nerve form in the thorax

Answer 2

The anterior vagal trunk

Question 3

What are the 2 other branches that arise from the vagus nerve in the thorax

Answer 3

The left recurrent laryngeal branch and cardiac branches

Question 4

Where does the left recurrent laryngeal branch of the vagus nerve run

Answer 4

It hooks under the aortic arch and ascends to innervate the intrinsic muscles of the larynx

Question 5

What is the function of the cardiac branches of the vagus nerve

Answer 5

Innervates regulate heart rate and provides visceral sensation to the organ

Question 6

Where do the vagal trunks pass through into the abdomen

Answer 6

They pass through the oesophageal hiatus

Question 7

Where does the phrenic nerve originate

Answer 7

Spinal roots c3,4,5

Question 8

What is the major contributor to the phrenic nerve

Answer 8

C4

Question 9

What is the course of the right phrenic

Answer 9

The right phrenic nerve passes over the lateral part of the right subclavian artery and enters the thorax through the superior thoracic aperture and descends anteriorly along the right lung root before coursing along the pericardium of the right atrium and then down to pierce the diaphragm at the inferior vena cava opening

Question 10

What is the course of the left phrenic nerve through the thorax

Answer 10

It passes anteriorly over the medial aspect of the left subclavian artery and enters the thorax through the superior thoracic aperture. It then descends the anterior of the left lung root before crossing the aortic arch and bypasses the vagus nerve. It then course along the pericardium of the left ventricle before piercing the diaphragm close to the apex of the heart