Autonomics Flashcards
Where do sympathetics to the head synapse?
One of three cervical ganglia (mostly in the superior cervical ganglion)
What is the pathway of preganglionic parasympathetics on their way to the pterygopalatine ganglion?
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
What is the high level overview of parasympathetics in the ciliary ganglion?
origin –> ganglion –> postganglionic path –> action
CN III (oculomotor) –> ciliary ganglion –> short ciliary nerves (V1 branch) –> sphincter pupillae, ciliary muscle
Where do parasympathetics that synapse in the ciliary ganglion come from?
Oculomotor nerve (III)
What is the high level overview of parasympathetics in the submandibular ganglion?
origin(s) –> ganglion –> postganglionic path –> action
CN VII (facial) –> chorda tympani –> lingual nerve (V3 branch) –> submandibular ganglion –> lingual nerve –> submandibular and sublingual glands
Where do parasympathetics that synapse in the pterygopalatine ganglion come from?
Facial nerve (VII)
What are the four peripheral ganglia for postganglionic parasympathetics?
Cilliary ganglion (from CN III)
Pterygopalatine ganglion and submandibular ganglion (From CN VII)
Otic ganglion (from CN IX)
What is the pathway of pregranglionic parasympathetics to the otic ganglion?
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
What four cranial nerves do parasympathetics emerge through?
Oculomotor (III), Facial (VII), Glossopharyngeal (IX), and Vagus (X)
What is the presentation of Horner’s syndrome?
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)
What is the high level overview of parasympathetics in the pterygopalatine ganglion?
origin(s) –> ganglion –> postganglionic path –> action
CN VII (facial nerve) –> greater petrosal nerve –> nerve of pterygoid canal –> pterygopalatine ganglion –> maxillary nerve (V2) branches –> nasal, palatal mucous glands, lacrimal gland
What is the path of postganglionic sympathetics in the head?
They travel into the head with the primary arteries and their branches
What are the nerve contents of the short ciliary nerves?
Somatic sensory V1 nerves
Postganglionic parasympathetics from ciliary ganglion
Postganglionic sympathetics from the ophthalmic artery/internal carotid sympathetic plexuses
Where do postganglionic parasympathetics go after the otic ganglion?
They follow the sensory V3 branch (auriculotemporal nerve) to deliver fibers to the parotid salivary gland.
What is the high level overview of parasympathetics in the otic ganglion?
origin(s) –> ganglion –> postganglionic path –> action
CN IX (glossopharyngeal) –> tympanic nerve –> tympanic plexus –> lesser petrosal nerve –> otic ganglion –> auriculotemporal nerve (V3) –> parotid gland
What is the pathway of preganglionic parasympathetics to the submandibular ganglion?
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
How do parasympathetics leave the ciliary ganglion after synapsing?
They leave the ganglion with the V1 branches off the nasociliary nerve (short ciliary nerves)
What is the function of postganglionic parasympathetics from the pterygopalatine ganglion?
They follow branches of V2 to innervate nasal and palatal mucosal glands and the lacrimal gland in the orbit
What are the main functions of sympathetics in the head?
Regulating vasoconstriction, pupil dilation and eyelid elevation, sweating
How do parasympathetics leave the pterygopalatine ganglion?
With sensory branches of the maxillary nerve (V2)
Describe the head/neck parasympathetics associated with the vagus nerve.
They run to mucosal glands in pharynx, larynx, and upper esophagus.
What is the function of sympathetics in the short ciliary nerves?
Innervate the dilator pupillae (opens pupil) and superior tarsal muscle (complete opening of eyelid)
Where do sympathetics to the head originate?
Upper thoracic levels of the spinal cord
What is the general pathway for delivery of postganglionic parasympathetics?
They follow the branches of the trigeminal nerve to be delivered to target regions
Where do postganglionic parasympathetics go after synapsing in the submandibular ganglion?
They re-enter the lingual nerve and go to submandibular and sublingual salivary glands (and small glands on the tongue)
What is the function of parasympathetics in the short ciliary nerves?
They pierce the back of the eyeball
Innervates sphincter pupillae (constricts pupil) and ciliary muscle (changes lens for close-up vision)
