Autonomics

Question 1

Where do sympathetics to the head synapse?

Answer 1

One of three cervical ganglia (mostly in the superior cervical ganglion)

Question 2

What is the pathway of preganglionic parasympathetics on their way to the pterygopalatine ganglion?

Answer 2

Facial nerve –> greater petrosal nerve –> merges with postganglionic sympathetics of the deep petrosal nerve (after crossing foramen lacerum) –> enters pterygoid canal as the nerve of pterygoid canal –> enters pterygopalatine ganglion

Question 3

What is the high level overview of parasympathetics in the ciliary ganglion?

origin –> ganglion –> postganglionic path –> action

Answer 3

CN III (oculomotor) –> ciliary ganglion –> short ciliary nerves (V1 branch) –> sphincter pupillae, ciliary muscle

Question 4

Where do parasympathetics that synapse in the ciliary ganglion come from?

Answer 4

Oculomotor nerve (III)

Question 5

What is the high level overview of parasympathetics in the submandibular ganglion?

origin(s) –> ganglion –> postganglionic path –> action

Answer 5

CN VII (facial) –> chorda tympani –> lingual nerve (V3 branch) –> submandibular ganglion –> lingual nerve –> submandibular and sublingual glands

Question 6

Where do parasympathetics that synapse in the pterygopalatine ganglion come from?

Answer 6

Facial nerve (VII)

Question 7

What are the four peripheral ganglia for postganglionic parasympathetics?

Answer 7

Cilliary ganglion (from CN III)

Pterygopalatine ganglion and submandibular ganglion (From CN VII)

Otic ganglion (from CN IX)

Question 8

What is the pathway of pregranglionic parasympathetics to the otic ganglion?

Answer 8

Glossopharyngeal (IX) nerve –> branches off to tympanic nerve –> re-enters skull through tympanic canal –> enters middle ear cavity (tympanic plexus forms) –> leaves plexus as lesser petrosal nerve –> lesser petrosal nerve leaves via lesser petrosal groove and then foramen ovale –> reaches otic ganglion

Question 9

What four cranial nerves do parasympathetics emerge through?

Answer 9

Oculomotor (III), Facial (VII), Glossopharyngeal (IX), and Vagus (X)

Question 10

What is the presentation of Horner’s syndrome?

Answer 10

Caused by interruption of sympathetics

Symptoms include:

• pupil constriction (loss of dilation ability)
• facial flushing (loss of vasoconstriction)
• loss of sweating
• ptosis (loss of superior tarsal muscle)

Question 11

What is the high level overview of parasympathetics in the pterygopalatine ganglion?

origin(s) –> ganglion –> postganglionic path –> action

Answer 11

CN VII (facial nerve) –> greater petrosal nerve –> nerve of pterygoid canal –> pterygopalatine ganglion –> maxillary nerve (V2) branches –> nasal, palatal mucous glands, lacrimal gland

Question 12

What is the path of postganglionic sympathetics in the head?

Answer 12

They travel into the head with the primary arteries and their branches

Question 13

What are the nerve contents of the short ciliary nerves?

Answer 13

Somatic sensory V1 nerves

Postganglionic parasympathetics from ciliary ganglion

Postganglionic sympathetics from the ophthalmic artery/internal carotid sympathetic plexuses

Question 14

Where do postganglionic parasympathetics go after the otic ganglion?

Answer 14

They follow the sensory V3 branch (auriculotemporal nerve) to deliver fibers to the parotid salivary gland.

Question 15

What is the high level overview of parasympathetics in the otic ganglion?

origin(s) –> ganglion –> postganglionic path –> action

Answer 15

CN IX (glossopharyngeal) –> tympanic nerve –> tympanic plexus –> lesser petrosal nerve –> otic ganglion –> auriculotemporal nerve (V3) –> parotid gland

Question 16

What is the pathway of preganglionic parasympathetics to the submandibular ganglion?

Answer 16

They originate with the facial nerve (VII) –> follow one trifurcation of VII (chorda tympani) –> exits temporal bone through petrotympanic fissure –> carries through infratemporal fossa –> JOINS TRIGEMINAL (V3) BEFORE GANGLION –> submandibular ganglion

Question 17

How do parasympathetics leave the ciliary ganglion after synapsing?

Answer 17

They leave the ganglion with the V1 branches off the nasociliary nerve (short ciliary nerves)

Question 18

What is the function of postganglionic parasympathetics from the pterygopalatine ganglion?

Answer 18

They follow branches of V2 to innervate nasal and palatal mucosal glands and the lacrimal gland in the orbit

Question 19

What are the main functions of sympathetics in the head?

Answer 19

Regulating vasoconstriction, pupil dilation and eyelid elevation, sweating

Question 20

How do parasympathetics leave the pterygopalatine ganglion?

Answer 20

With sensory branches of the maxillary nerve (V2)

Question 21

Describe the head/neck parasympathetics associated with the vagus nerve.

Answer 21

They run to mucosal glands in pharynx, larynx, and upper esophagus.

Question 22

What is the function of sympathetics in the short ciliary nerves?

Answer 22

Innervate the dilator pupillae (opens pupil) and superior tarsal muscle (complete opening of eyelid)

Question 23

Where do sympathetics to the head originate?

Answer 23

Upper thoracic levels of the spinal cord

Question 24

What is the general pathway for delivery of postganglionic parasympathetics?

Answer 24

They follow the branches of the trigeminal nerve to be delivered to target regions

Question 25

Where do postganglionic parasympathetics go after synapsing in the submandibular ganglion?

Answer 25

They re-enter the lingual nerve and go to submandibular and sublingual salivary glands (and small glands on the tongue)

Question 26

What is the function of parasympathetics in the short ciliary nerves?

Answer 26

They pierce the back of the eyeball

Innervates sphincter pupillae (constricts pupil) and ciliary muscle (changes lens for close-up vision)