Vagus Nerve

Question 1

Origin

Answer 1

Same except parasympathetic from dorsal nucleus vagus

Question 2

Course

Answer 2

1. Leaves skull via jugular foramen
2. Descend inside carotid sheath between ICA and IJV then between CCA and IJV
3. Enters thorax by passing in front of 1st part subclavian artery
   Has 2 ganglia superior (inside jugular foramen) and inferior ( inside carotid sheath)

Question 3

Branches

Answer 3

2 branches from superior ganglion:
1. Meningeal
2. Auricular
2 branches from inferior ganglion:
1. Pharyngeal
2. Superior laryngeal
2 cardiac branches:
1. Superior
2. Inferior
Recurrent laryngeal

Question 4

Meningeal

Answer 4

Posterior cranial fossa dura

Question 5

Auricular

Answer 5

1. External auditory meatus
2. Ear drum

Question 6

Pharyngeal course

Answer 6

Passes between ECA and ICA ending in pharyngeal plexus on middle constrictor muscle

Question 7

Pharyngeal supply

Answer 7

1. All pharynx muscles except Stylopharyngeus
2. All soft palate muscles except tensor palati (contains fibers from cranial root accesory nerve)

Question 8

Superior laryngeal

Answer 8

Passes deep to ECA and ICA dividing into:
1. Internal laryngeal
2. External laryngeal

Question 9

Internal laryngeal

Answer 9

Pierces thyrohyoid membrane to larynx mucosa above vocal cords and epiglottis

Question 10

External laryngeal

Answer 10

Accompanies superior thyroid artery to circothyroid or larynx

Question 11

External laryngeal supply

Answer 11

Gives a twig to pharynx inferior constrictor

Question 12

Cardiac branches

Answer 12

To cardiac plexus heart

Question 13

Recurrent laryngeal right

Answer 13

Arises from right vagus in root of neck (hooking around subclavian artery)

Question 14

Recurrent laryngeal left

Answer 14

Arises from left vagus in thorax (hooking around arch aorta)

Question 15

Recurrent laryngeal

Answer 15

Both ascend between trachea and esophagus entering larynx deep to inferior constrictor lower border

Question 16

Recurrent laryngeal branches

Answer 16

1. Motor
2. Sensory
3. Branches to trachea, esophagus, and heart

Question 17

Motor

Answer 17

1. All muscles larynx (except cricothyroid)
2. Inferior constrictor

Question 18

Sensory

Answer 18

Mucosa larynx below vocal cords