Wednesday, 3-23-ANS of the Head (Stephens) Flashcards
The sympathetic trunk is located ___ to the common carotid and ___ to the longs colli and capitus muscles
Posterior
Anterior
Where are preganglionic sympathetic neurons located?
Preganglionic sympathetic fibers to the head and neck originate in preganglionic sympathetic cell bodies located in the intermediolateral cell column of T1-2
Where are postganglionic sympathetic neurons located?
They originate from postganglionic sympathetic neurons located in one of the cervical sympathetic ganglia
There are no preganglionic sympathetic fibers in the __.
Head
The preganglionic sympathetic fibers in the neck are restricted to the cervical sympathetic trunk where they synapse upon postganglionic neurons
How do preganglionic sympathetic fibers exit the SC?
Via the ventral root, travel through the white ramus to the sympathetic trunk, where they ascend in the sympathetic chain before terminating in 1 of the cervical sympathetic ganglia
The ___ ganglion is a large elliptical ganglion located posterior to the internal carotid artery, embedded in the pre vertebral fascia at the level of C1-2 and on the surface of the longus capitus muscle at the level of the 1st cervical vertebra
superior cervical
Where does the superior cervical ganglion primarily receive its preganglionic sympathetic fibers from?
Mainly from T1
The ___ plexus follows the internal carotid a. into the skull and branches at the level of the carotid siphon
internal carotid
-The internal carotid n. leaves the superior cervical ganglion and forms the internal carotid plexus in the tunica adventitia of the internal carotid
What are the 4 branches from the internal carotid plexus?
- Perivascular
- Sympathetic branch to the ciliary ganglion
- Deep petrosal n.
- Carotico-tympanic n.
Where does the vertebral ganglion sit?
On the vertebral a.
-The vertebral ganglion is located at the level of C7 anterior to the vertebral a.
The __ ganglion sends postganglionic sympathetic fibers to the 6th cervical n. and vertebral plexus
vertebral
The vertebral ganglion sends a cord, the ___, which loops around the anterior surface of the subclavian a. and terminates in the inferior cervical or stellate ganglion
ansa subclavia
___ is a common sequela of SC and neck trauma. It may caused by interruption of the cervical sympathetic trunk and/or transection of the SC above the level of T1
Horner’s syndrome
List signs and symptoms of Horner’s syndrome:
- Slight ptosis (drooping) of the upper lid due to paralysis of the tarsal muscle
- Pupillary constriction
- Anhydrosis (no sweating) and blushing
- Enopthalmos due to paralysis of orbital is muscle of Muller
- Effects of Horner’s is usually transient
A SC injury above the level of ___ is usually the main cause of Horner’s syndrome
T1
Preganglionic parasympathetic neurons are located in ___ nuclei of the brainstem and SC
craniosacral
Regarding the head and neck, the parasympathetic nuclei are comprised of preganglionic parasympathetic axons coursing with these cranial nerves:
III, VII, IX, and X
Where does the Ediner-westphal nucleus send preganglionic parasympathetic fibers?
Ciliary ganglion
Postganglionic parasympathetic fibers from the ciliary ganglion travel and synapse where?
Ciliary muscles of the lens and the sphincter pupillage muscles of the iris
Preganglionic parasympathetic axons from the edinger-westphal nucleus travel on what CN?
III
Pupillary constriction and thickening of the lens (near vision) are ___ responses
parasympathetic
The sympathetic branch to the ciliary ganglion is a branch of the ___ plexus
internal carotid
The sympathetic branch to the ciliary ganglion passes through the cavernous sinus, superior orbital fissure, and the ciliary ganglion before terminating as short ciliary nerves to the eyeball. These postganglionic sympathetic fibers innervate the ___ muscles
dilator pupillae and tarsal muscles
Where does the superior salivatory nucleus send preganglionic parasympathetic fibers to?
Sphenopalatine and submandibular ganglia