Cranial Autonomics

Question 1

Parasympathetic secretomotor neurons innervate ____

Answer 1

. Mucosal glands
. 3 pairs of salivary glands
. Lacrimal gland
. Spinchter pupillae and ciliary mm. In eye

Question 2

The sympathetic division innervates what components of head and neck?

Answer 2

. Vascular smooth m., sweat glands, and arrector pili mm.

. Dilator pupillae and sup. Tarsal m. In orbit

Question 3

T/F both sympathetic and parasympathetic fibers modulate glandular secretions, but differentially affect the composition of secretions

Answer 3

T

Question 4

All sympathetic fibers in head or pre or postganglionic?

Answer 4

Postganglionic

. Originate from T1-L2 spinal cord segments in one of 3 cervical ganglion (mostly sup. Cervical ganglion)

Question 5

Routes of distribution of postganglionic fibers from sup. Cervical ganglia

Answer 5

. Arteries
. Cranial n.
. Direct visceral branches

Question 6

Sympathetic functions of head an neck

Answer 6

. Regulation of vasoconstriction
. Pupil dilation
. Eyelid elevation
. Sweating

Question 7

Horner’s syndrome

Answer 7

. Interruption of sympathetics to head and neck from compression lesion of sympathetic trunk in sup. Mediastinum
. Have miosis (pupil constriction from dilator pupillae paralysis), ptosis, flushing of face, and hemianhydrosis (absence of sweating on affected side from lack of sympathetics)

Question 8

Cranial preganglionic parasympathetic fibers merge from neurons originating in _____

Answer 8

4 nuclei w/in brainstem

Question 9

Cranial nn. W/ parasympathetic fibers

Answer 9

. CN III, VII, IX, and X
. III, VII, and IX have 4 parasympathetic ganglia in the head (1 CN III, 2 for CN VII, 1 for CN IX)
. Closely assoc. w/ CN V and are delivered ot target organs in head and neck by hitchhiking on CN V branches

Question 10

T/F the vagus has no named discrete ganglionic mass assoc. w/ it

Answer 10

T, it only has small diffuse ganglia in organ/target walls

Question 11

Does the trigeminal n. Have intrinsic parasympathetic outflow?

Answer 11

F

. Only involved in distributing fibers

Question 12

Function of parasympathetics in head and neck

Answer 12

. Affect secretion of lacrimal, salivary, and mucosal glands of oral and nasal cavities and sinuses
. Only smooth mm. Innervated by these fibers are the ciliary mm. And sphincter pupillae in eye

Question 13

Vagus innervation to head and neck

Answer 13

. Has little parasympathetic innervation in head and neck
. Has some fibers that run to mucosal glands in pharynx, larynx, and upper esophagus (not glands in upper pharynx, nasal cavity, and paranasal sinuses)
. Gives off cervical cardiac nn. In neck that pass into thorac and bring fibers to heart

Question 14

General scheme of al 4 parasympathetic ganglia

Answer 14

. Sensory fibers from branch of CN V traverse each ganglion
. Postganglionic sympathetic fibers from sup. Cervical ganglion traverse each ganglion
. Preganglionic parasympathetic fibers: synapse w/ cell bodies of postganglionic parasympathetic neurons in ganglia, no synapses other than these occur in parasympathetic ganglia

Question 15

Cranial nn. W/ parasympathetic outflow

Answer 15

. CN III
. CN VII
. CN IX
. CN X

Question 16

CN III parasympathetic pathway

Answer 16

. Preganglionic fibers arise from neurons in Edinger-Westphal nucleus (midbrain) and leave brain stem in CN III
. Synapse in ciliary ganglion
. Postganglionic fibers innervate sphincter pupillae m. (Constricts pupil) and ciliary mm. (Accommodation of lens to near vision)

Question 17

CN VII parasympathetic pathway

Answer 17

. 2 preganglionic components that arise from sup. Salivatory nucleus
. Fibers exit brainstem in nervous intermedius, pass through sensory geniculate ganglion
. Continue in the greater petrosal n. To reach and synapse in pterygopalatine ganglion
. Postganglionic secretomotor fibers go to lacrimal gland and the mucous glands of the nasal cavity and palate
. Sup. Salvatpry nucleus has Preganglionic fibers that exit nervus intermedius, continue in chorda tympani and then in lingual n. To reach and synapse in submandibular ganglion
. Postganglionic secretomotor fibers got o submandibular and sublingual salivary glands

Question 18

Glossopharyngeal n. Parasympathetic pathway

Answer 18

. Preganglionic fibers arise from inf. Salivatory nucleus
. Travel in tympanic branch of CN IX and leave tympanic cavity as the lesser petrosal n.
. Preganglionic parasympathetic secretomotor fibers go to parotid salivary gland

Question 19

Vagus n. Parasympathetic pathway

Answer 19

. Preganglionic fibers arise from 2 sites w/in the medulla oblongata
. Visceromotor fibers: nucleus ambiguous is source of visceromotor fibers that slow heart, inc. peristaltic wave of GI tract, and make other smooth m. Contract
. Secretomotor fibers: dorsal motor nucleus of the vagus, source of secretory fibers to various autonomic ganglia that lie near thoracic and abdominal organs

Question 20

Ciliary ganglion

Answer 20

. Parasympathetic preganglionic secretomotor fibers leave brainstem in oculomotor n.
. Fibers in inf. Division of CN III branch anterosup. To ciliary ganglion (located lat. to large optic n.) near apex of orbit and synapse
. Postganglionic fibers leave ganglion w/ somatic sensory branches off nasociliary n. (Short ciliary nn.)

Question 21

Short ciliary nn.

Answer 21

. Contain sympathetic postganglionic fibers from ophthalmic a./internal carotid sympathetic plexuses
. Travel to the back of eyeball, pierce it, and deliver sensory, postganglionic parasympathetic and postganglionic sympathetic fibers to eyeball

Question 22

Pterygopalatine ganglion

Answer 22

. Parasympathetic Preganglionic secretofibers leave brainstem in facial n. That enters internal acoustic meatus
. Trifurcates w/in petrous temporal bone, primary branch exits through hiatus as greater petrosal n.
. Combined preganglionic parasympathetic and postganglionic sympathetic n. Enters pterygoid canal as n. Of the pterygoid canal (Vidian n.)
. Parasympathetic secretomotor fibers synapse w/ ganglion and course to sensory branches of maxillary n. To nasal and palatal mucosal glands, zygomaticotemporal n. And lacrimal n. To lacrimal gland
. Sympathetic fibers pass ganglion to distribute to same targets w/ CN V branches

Question 23

Greater petrosal n.

Answer 23

. Courses across foramen lacerum
. Merges w/ postganglionic sympathetic fibers carried in deep petrosal n. Coming off sympathetic plexus surrounding the internal carotid a.

Question 24

Vidian n.

Answer 24

. Exits into pterygopalatine fossa where it enters pterygopalatine ganglion assoc. w/ sensory branches of maxillary n. (Entered pterygopalatine fossa through foramen rotundum)

Question 25

Submandibular ganglion

Answer 25

. Parasympathetic Preganglionic secretomotor fibers leave brainstem in CN VII that enters internal acoustic meatus and trifurcates w/in petrous temporal bone . Primary branch (chorda tympani) exits through the petrotympanic fissure post. To mandibular fossa . Carries preganglionic parasympathetic secretomotor fibers plus special sensory taste fibers to ant. 2/3 tongue thorough infratemporal fossa and joins w/ lingual n.

Question 26

Lingual n.

Answer 26

. Parasympathetic fibers synapse in submandibular ganglion . Postganglionic parasympathetic fibers re-enter lingual n. To be distributed to submandibular and sublingual salivary glands (only time in head that parasympathetic fibers join a trigeminal branch prior to synapsing in their ganglion)

Question 27

Zones targeted by parasympathetic secretomotor fibers in CN VII

Answer 27

. All 3 zones of trigeminal innervation (orbit-lacrimal gland, midface-mucosal glands mandible0submandibular/sublingual glands)

Question 28

Otic ganglion

Answer 28

. Parasympathetic preganglionic secretomotor fibers leave brainstem in CN IX . N. Exits neurocranium through jugular foramen, gives off tympanic branch carrying parasympathetic fibers . Tympanic n. Re-enters skull via tympanic canal, passes to middle ear cavity forming tympanic plexus . Leaves cavity ant. As lesser petrosal n. In petrosal temporal in lesser petrosal hiatus . Lesser petrosal n. Leaves skul via foramen ovale and synapse on otic ganglion (med. surface CN V3) . Postganglionic parasympathetic delivered to parotid in auriculotemporal n. . Postganglionic sympathetic to parotid delivered on aa. Branches

Question 29

Simplified CN III parasympathetic pathway

Answer 29

. CN III . Ciliary ganglion . Short ciliary nn. . Sphincter pupillae, ciliary mm.

Question 30

Simplified CN VII to pterygopalatine parasympathetic pathway

Answer 30

``` . CN VII . Greater petrosal n. . N. Of pterygoid canal . Pterygopalatine ganglion . Maxillary n. Branches . Nasal, palatal mucous glands and lacrimal gland (via zygomaticotemporal to lacrimal n.) ```

Question 31

Simplified CN VII to submandibular ganglion parasympathetic pathway

Answer 31

``` . CN VII . Chorda tympani . Lingual n. . Submandibular ganglion . Lingual n. . Submandibular and sublingual glands ```

Question 32

Simplified CN IX parasympathetic pathway

Answer 32

``` . CN IX . Tympanic n. . Tympanic plexus . Lesser petrosal n. . Otic ganglion . Auriculotemporal n. . Parotid gland ```

Question 33

Sympathetic innervation of eye

Answer 33

. T1-2 . Preganglionic synapse at sup. Cervical ganglion . Course of fibers: internal carotid a. Plexus to ciliary ganglion to nasociliary n. Or along vessels . Function: dilation of pupil, vasoconstriction, elevation of eyelid via tarsal n.

Question 34

Sympathetic innervation lacrimal gland

Answer 34

. T1-2 . Sup. Cervical ganglion site of synapse . Corse: internal carotid a. Plexus, deep petrosal n., n. Pterygoid canal, pterygopalatine ganglion, lacrimal n. . Functions: vasoconstriction

Question 35

Sympathetic innervation to parotid gland

Answer 35

. T1-2 . Synapse at sup. Cervical ganglia . Course: external carotid a. Plexus, maxillary and middle meningeal a. Plexuses, otic ganglion, parotid branches . Function: vasoconstriction

Question 36

Sympathetic innervation of submandibular and sublingual glands

Answer 36

. T1-4 . Synapse at all cervical ganglia . Course: external carotid a. Plexus to submandibular ganglion to direct glandular filaments or along vessels . Function: vasocontriction