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1. Anatomy - BLOCK 4 > Cranial Nerves > Flashcards

Cranial Nerves Flashcards

1
Q

Identify the Cranial Nerves:

A
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2
Q

Which CN are solely sensory?

A

** Sensory**

  1. Olfactory (CN I)
  2. Optic (CN II)
  3. Vestibulocochlear (CN VIII)
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3
Q

Which CN are solely Motor?

A

Motor

  1. Trochlear (CN IV)
  2. Abducens (CN VI)
  3. Accessory (CN XI)
  4. Hypoglossal (CN XII)
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4
Q

Which CN are mixed (Sensory/Motor/parasympathetic)?

A

Mixed

  1. Oculomotor (CN III)
  2. Trigeminal (CN V)
  3. Facial (CN VII)
  4. Glossopharyngeal (CN IX)
  5. Vagus (CN X)
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5
Q

CN I: Olfactory nerve

(special sensory)

  • where is smell “picked up”?
  • which bone does the cribiform plate belong to?
  • where do the fila olfactoria synapse?
A
  • by the fila olfactoria (olfactory epithelium)
  • cribriform plate of ethmoid
  • synapse on olfactory bulb (of telencephalon)
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6
Q

What is the ONLY cranial nerve capable of regeneration after destruction?

A

Olfactory nerve (CN I)

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7
Q

CN II: Optic nerve

(special sensory; not a real ‘nerve’)

  • Carries information from what structures?
  • what is the entry point for optic nerve into orbit?
  • Cross-over of fibers = ??
A
  • from retinal photoreceptors
  • Optic canal
  • optic chiasm
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8
Q

Visual field is…

A

…what our eyes see

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9
Q

** Medial** ½ of retina is…

A

▪ nasal = located toward the nose (STRUCTURE)

▪  receives information from **temporal visual field** (FUNCTION)
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10
Q

Lateral ½ of retina is…

A

▪ temporal = located toward the temple of skull (STRUCTURE)

▪  receives information from **nasal visual field** (FUNCTION)
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11
Q

Which visual field = ipsilateral visual field of an eye?

** **(e.g., right visual field of right eye)

A

Temporal visual field

*(wider than nasal field)

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12
Q

Which visual field = contralateral visual field of an eye?

(e.g., left visual field of right eye)

A

Nasal visual field

*(narrower than temporal field)

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13
Q

What do the visual fields project into?

What causes 3D, stereoscopic, binocular vision, etc?

A
  • into retinal receptors + (R/L) optical cortices in brain
  • caused by overlap of right and left visual fields
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14
Q
A

Right optic tract = Left visual field

Left optic tract = Right visual field

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15
Q

Optic nerve damage = ??

A

(monocular blindness): Blindness in one eye.

Loss of both visual fields on affected side

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16
Q

Optic tract damage = ??

A

(homonymous hemianopia): Loss of peripheral vision on opposite side

e.g., right optic tract damage → loss of vision in the left visual fields of both eyes.

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17
Q

Optic chiasm damage = ??

A

(bi-temporal hemianopia): Loss of temporal visual fields on both sides → tunnel vision

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18
Q

CN III: Oculomotor nerve

(motor w. parasympathetic)

  • Exits cranial cavity and enters orbit through…?
  • Somatic motor fibers to what 5 mm.?
A
  • superior orbital fissure
  • superior rectus (SR) + inferior rectus (IR) + medial rectus (MR) + inferior oblique (IO) + levator palpebrae superioris (LPS)
  • *LPS also contains smooth muscle fibers (superior tarsal m.) that receive sympathetic innervation**
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19
Q

CN III: Oculomotor nerve

(motor w. parasympathetic)

  • Parasympathetic innervation to…? (2mm.)
  • Pre-ganglionic parasympathetic fibers to…?
  • Post-ganglionic parasympathetic fibers travel via…?
  • Parasympathetic innervation allows…
A
  • ciliary m. + constrictor pupillae m.
  • fibers to ciliary ganglion
  • travel via short ciliary nn.
  • allows: pupillary light reflex + pupillary accommodation/convergence reflex
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20
Q
  • Constrictor + dilator pupillae* mm. are located where?
  • what are their innervations? (different)
A
  • in iris
  • costrictor = parasympathetic (CNIII)
  • dilator = sympathetic (superior cervical ganglion)
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21
Q

CN IV: Trochlear nerve

(motor)

  • Exits cranial cavity and enters orbit via…?
  • Somatic motor innervation to…? (1m.)
A
  • superior orbital fissure
  • superior oblique m. (SO)
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22
Q

CN VI: Abducens nerve

(motor)

  • Exits cranial cavity and enters orbit via…?
  • Somatic motor innervation to…? (1m.)
A
  • superior orbital fissure
  • lateral rectus m. (LR)
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23
Q

Medial rectus (MR)

  • Action = eye looking straight ahead (what it’s capable of)?
  • Function = When and how it is actually used?
A

action = Adduction

function = Adduction

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24
Q

Lateral rectus (LR)

  • Action = eye looking straight ahead (what it’s capable of)?
  • Function = When and how it is actually used?
A

action = Abduction

function = Abduction

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25
Q

Superior rectus (SR)

  • Action = eye looking straight ahead (what it’s capable of)?
  • Function = When and how it is actually used?
A

action = Elevation + Incycloduction + Adduction

function = Elevation of abducted eye

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26
Q

Inferior rectus (IR)

  • Action = eye looking straight ahead (what it’s capable of)?
  • Function = When and how it is actually used?
A

action = Depression + Excycloduction + Adduction

function = Depression of abducted eye

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27
Q

Inferior oblique (IO)

  • Action = eye looking straight ahead (what it’s capable of)?
  • Function = When and how it is actually used?
A

action = Elevation + Excycloduction + Abduction

function = Elevation of adducted eye

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28
Q

Superior oblique (SO)

  • Action = eye looking straight ahead (what it’s capable of)?
  • Function = When and how it is actually used?
A

action = Depression + Incycloduction + Abduction

function = Depression of adducted eye

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29
Q

Functions of Extraocular Muscles

*how they are actually used (and how to test them in a patient)

A
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30
Q

Pathology: Oculomotor nerve (CN III)

Paralysis of the somatic fibers of CN III leads to…

A

- ptosis (“dropping eyelid”)

- immobility of eyeball, which assumes an abducted (down-and-out) position

*(unopposed LR = CN VI) *

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31
Q

Pathology: Oculomotor nerve (CN III)

Paralysis of parasympathetic fibers of oculomotor nerve (CN III) causes…

A

- dilated pupil

  • loss of normal pupillary reflex
32
Q

Pathology: Trochlear nerve (CN IV)

If superior oblique is paralyzed…

A
  • eyeball cannot be depressed when it is adducted, or looking straight ahead
  • double vision occurs on attempting to look downward
  • (e.g., during reading or walking downhill)*
33
Q

Pathology: Abducens nerve (VI)

If lateral rectus is paralyzed…

A
  • eyeball assumes an adducted position at rest (unopposed MR) = double vision
    • view objects w. head turned (normal eye required to abduct) = avoids dbl vision
34
Q

CN V: Trigeminal nerve

(sensory, motor, parasympathetic)

  • what are the 3 divisions?
  • what areas does it supply somatic sensory innervation to ?
  • what areas does it supply somatic motor innervation to?
A

3 divisions:

Ÿ ophthalmic (V1) → somatic sensory

Ÿ maxillary (V2) → somatic sensory

Ÿ mandibular (V3) → somatic sensory + motor

**all carry post-ganglionic parasympathetic fibers

- somatic sensory nerve to…

face + orbit + nasal cavity + oral cavity + cranial blood vessels + meninges

V3 provides somatic motor innervation to…

muscles derived from 1st pharyngeal arch (i.e. muscles of mastication)

35
Q

Trigeminal nerve: Trigeminal ganglion

* Leaves brainstem in 2 separate roots:

  • sensory
  • motor
    1. Trigeminal cave in front of petrous temporal bone contains…
    2. what divisions come from the trigeminal ganglion?
A
  1. trigeminal (semilunar) ganglion (sensory fiber roots)
  2. 3 sensory divisions (V1 + V2 + V3)
    * *motor fibers NOT part of ganglion; join V3*
36
Q

CN V1: Ophthalmic division of CN V

  1. Enters orbit from cranial cavity through…?
  2. Sensory (somatic + visceral) innervation to…?
  3. 3 branches?
A
  1. superior orbital fissure
  2. skin of upper face and forehead + conjunctiva and cornea + partial nasal cavity
  3. Lacrimal n. + Frontal n. + Nasocilliary n.
    * (sensory + post-ganglionic sympathetic)*
37
Q

CN V1

Lacrimal n. innervates?

A

conjunctiva + lateral part of upper eyelid + lacrimal gland

(sensory and post-ganglionic sympathetic)

38
Q

CN V1

Frontal n. branches + innervations? (2)

Ÿ
A

Supraorbital n. → conjunctiva + skin of upper eyelid + skin of lower medial part of forehead

** Ÿ Supratrochlear n.** → conjunctiva + upper eyelid + forehead + middle of scalp

(sensory + post-ganglionic sympathetic)

39
Q

CN V1

Nasocilliary n. branches + innervations? (3)

A

Long ciliary nn. → eyeball (sensory + post-ganglionic sympathetic)

** Ÿ Infratrochlear n**. → lacrimal sac + upper and lower eyelids (medial parts) + skin of upper ½ of nose

** Ÿ Ethmoidal nn.** (anterior and posterior) → anterior cranial fossa + nasal cavity + skin of lower ½ of nose + posterior ethmoidal sinus + sphenoid sinus

40
Q

CN V2: Maxillary division of CN V

  1. Sensory innervation to…?
  2. Exits cranial cavity (+ enters pterygopalatine fossa) through…?
  3. passes anteriorly through fossa + exits through inferior orbital fissure + infraorbital foramen as …?
  4. CN V2 connects with pterygopalatine ganglion though…
A
  1. skin of midface + nasal cavity + maxillary sinus + palate + upper dentition
  2. foramen rotundum
  3. infra-orbital n.
  4. ganglionic branches (aka pterygopalatine nn.)

( post-ganglionic parasympathetic fibers: ganglion –> CN V2;

sensory fibers: CN V2 –> ganglion)

41
Q

CN V2: Maxillary division of CN V

Name the 6 branches + their innervations:

A
  1. Infraorbital n. → skin of lower eyelid + upper lip + side of nose + front of cheek + nasal vestibule
  2. Superior alveolar nn. → Upper dentition + maxillary sinus
  3. Greater palatine n. → lateral nasal wall + palate
  4. Lesser palatine n(n). → soft palate
  5. Nasopalatine n. → nasal septum + anterior part of hard palate
  6. Zygomatic n. → small regions of skin behind orbit & above cheek bone
42
Q

CN V3: Mandibular division of CN V

(sensory + motor fibers)

  1. Exits cranial cavity (+ enters infratemporal fossa) via…
  2. Name the 5 sensory branches + innervations:
A
  1. foramen ovale

2. sensory branches:

  • Auriculotemporal n. → external auditory meatus + eardrum + superior ½ of auricle + most of temple
  • Inferior alveolar n. → lower jaw + mandible
  • Mental n. → skin over front ½ of mandible and chin
  • Lingual n. → general sensation from anterior ⅔ of tongue + taste from anterior ⅔ of tongue to chorda tympani (CN VII)
  • Buccal n. → Skin and mucous membrane of cheek
43
Q

CN V3: Mandibular division of CN V

Name the 2 branches carrying parasympathetic fibers:

A

Auriculotemporal n. → post-ganglionic parasympathetic: otic ganglion –> parotid gland

Lingual n. → pre-ganglionic parasympathetic: chorda tympani –> submandibular ganglion, + post-ganglionic fibers: –> sublingual gland

44
Q

CN V3: Mandibular division of CN V

Name the 7 motor branches + innervations:

(7nn. –> 8 mm.)

A

Masseteric n. → masseter

Deep temporal nn. → temporalis

N. to medial pterygoid → medial pterygoid

N. to lateral pterygoid → lateral pterygoid

*N. to mylohyoid → mylohyoid + *anterior belly of digastric

N. to tensor veli palatini → tensor veli palatini

N. to tensor tympani → tensor tympani

45
Q

Trigeminal nerve: Clinical Considerations

pain, tingling, or numbness from the skin supplied by its division

= damage to what division(s)?

A

Damage to any division

46
Q

Trigeminal nerve: Clinical Considerations

Loss of corneal reflex (the blink that occurs when cornea is touched)

= damage to what division(s)?

A

Damage to CN V1

47
Q

Trigeminal nerve: Clinical Considerations
Weakness/paralysis of chewing muscles (always symptomatic)

    • possibly visible loss of muscle mass (wasting) of temporalis/masseter*

= damage to what division(s)?

A

Damage to CN V3

48
Q

Trigeminal nerve: Clinical Considerations (CN V3)

Unilateral paralysis of lateral pterygoid =??

A

Deviation of jaw to the ipsilateral side on opening the mouth = drop jaw to same side

49
Q

CN VII: Facial nerve

1. Somatic motor to…

● facial expression mm.

● stylohyoid + stapedius + digastric (posterior belly) (mm. fr. 2nd pharyngeal arch)

2. Somatic sensory from…

● skin of external auditory meatus

3. Special sensory (taste) from…

● anterior ⅔ of tongue

4. Pre-ganglionic parasympathetic to lacrimal gland via…

● greater petrosal n. + pterygopalatine ganglion

5. Pre-ganglionic parasympathetic to salivary glands via…

● chorda tympani + submandibular ganglion

A
50
Q

CN VII: Facial nerve

Leaves brainstem as which two separate bundles?

A
  1. somatic motor root
  2. nervous intermedius (with sensory + parasympathetic roots)
51
Q

CN VII: Facial nerve

  1. Nervous intermedius + somatic motor root → ??
  2. where does this nerve bifurcata + what are its branches?
  3. where are the sensory cell bodies housed?
A
  1. facial n. (in the internal auditory meatus)
  2. @ genu (within petrous temporal)
    - greater petrosal n. (smaller; anteriomedially)
    - facial n.** **(larger; posterolaterally)
  3. ** Geniculate ganglion**
52
Q

CN VII: Facial nerve

diagram

A
53
Q

CN VII: Greater Petrosal n.

Greater petrosal n. (pre-ganglionic parasympathetic) + Deep petrosal n. (post-ganglionic sympathetic) → N. of pterygoid canal

N. of pterygoid canal enters pterygoid canal through cartilage of foramen lacerum

  • parasympathetic part → Pterygopalatine ganglion (synapse)

Post-ganglionic parasympathetic fibers → Mucous glands (via CN V2 branches) + Lacrimal gland (via direct branches)

A
54
Q

CN VII: Chorda Tympani

(pre-ganglionic parasympathetic)

Comes out of facial n. (posterior wall of tympanic cavity)

middle ear: chorda tympani passes superior to tympanic membrane (b/t malleus + incus)

Exits cranial cavity through petrotympanic fissure; joins lingual n. (infra-temporal fossa)

Lingual n. = pre-ganglionic parasympathetic fibers: chorda tympani –> submandibular ganglion (synapse)

Post-ganglionic fibers –> submandibular gland (direct branches) + sublingual gland (via lingual n.)

Taste sensation from anterior ⅔ of tongue to brain

A
55
Q

CN VII: Muscular Component

Facial n. → Stapedius m. (by n. to stapedius in tympanic cavity)

Facial n. exits cranial cavity through s**tylomastoid foramen; **muscular branches to…

- occipitalis + posterior belly of digastric + stylohyoid + auricularis posterior mm.

The parotid plexus in the parotid gland is made up of? (5nn.)

A

** Temporal** → Frontalis + Orbicularis oculi mm.

Zygomatic → Orbicularis oculi + midfacial mm.

Buccal → Buccinator + Orbicularis oris mm.

Mandibular → Orbicularis oris m. + depressors of lower lip

** Cervical** → Platysma

56
Q

Pathology of CN VII: Bell’s Palsy

Inflammation of facial n. in facial canal

Paralysis of facial muscles on ipsilateral side

May involve chorda tympani + n. to stapedius

Symptoms (on the affected side) ? (7)

A

● absence of normal creases in forehead and nasolabial groove

● wider than normal palpebral fissure

● drooping corner of mouth

● accumulation of excess tears (because blinking is impossible)

● accumulation of food between cheek and lower gum during chewing (inactive buccinator)

● lack of taste sensation on the anterior ⅔ of tongue (paralyzed chorda tympani)

● hypersensitivity (hyperacusis) to sound (regular/loud) (paralyzed n. to stapedius)

57
Q

CN VIII: Vestibulocochlear nerve

sensory

  1. Enters temporal bone via…?
  2. Name the 2 branches + innervations:
  3. provides sepcial sensory innervation to…? (3 structures)
A
  1. internal auditory meatus
  2. branches:

Vestibular n. → Semicircular canals + Saccule + Utricle

Cochlear n. → Cochlea

3. Special sensory to…

▪ cochlea (hearing)

▪ semicircular canals (angular acceleration)

▪ saccule + utricle (linear acceleration + head orientation)

58
Q

CN IX: Glossopharyngeal nerve

(motor, sensory, parasympathetic)

  1. Exits cranial cavity through…
  2. somatic sensory to…? (6 structures)
  3. taste sensation from…?
  4. visceral sensory to…? ( structure)
  5. somatic motor to…? (1)
  6. pre-ganglionic parasympathetic to…? (2)
A
  1. jugular foramen

2. Somatic sensory to…

Ÿ  middle ear

Ÿ  mastoid air cells

Ÿ  auditory tube

Ÿ  oropharynx

Ÿ  pharyngeal tonsil

Ÿ  posterior ⅓ of tongue + vallate papillae

3. Taste sensation from…

·  posterior ⅓ of tongue

vallate papillae

4. Visceral sensory to…

carotid sinus + carotid body

5. Somatic motor to…

stylopharyngeus m.

6. Pre-ganglionic parasympathetic to…

Ÿ  parotid gland (via otic ganglion)

Ÿ  carotid sinus + carotid body
59
Q

CN IX: Glossopharyngeal nerve

(diagram)

A
60
Q

CN IX: Glossopharyngeal nerve

Tympanic nerve…

· carries sensory + pre-ganglionic parasympathetic fibers

· arises in jugular foramen, and enters middle ear

· joins caroticotympanic n. (branch fr. internal carotid plexus) [+ branch from CN VII]

· forms tympanic plexus

A
61
Q

CN IX: Glossopharyngeal nerve

Lesser petrosal n….

· emerges from tympanic plexus

· carries pre-ganglionic parasympathetic fibers

Exits cranial cavity through…

· foramen ovale

In the infratemporal fossa, meets…

· otic ganglion (synapse)

Post-ganglionic fibers join…

· auriculotemporal n. (CN V3)

Auriculotemporal n. carries post-ganglionic parasympathetic fibers to…

· parotid gland

A
62
Q

Carotid sinus and body:

A

sensory and parasympathetic innervations by carotid n. (CN IX)

63
Q

CN X: Vagus nerve

Exits cranial cavity through…

jugular foramen

Somatic motor innervation to…

muscles of the palate (EXCEPT tensor veli palatini)

muscles of pharynx (EXCEPT stylopharyngeus)

striated muscles of upper esophagus

intrinsic muscles of larynx

Sensory innervation to…

laryngopharynx + larynx + upper esophagus + trachea + carotid body + skin of external auditory meatus

Parasympathetic innervation to…

pharynx + larynx + thoracic and abdominal viscera up to left colic (= splenic) flexure

A

* provides somatic motor innervation to muscles derived from 4th and 6th pharyngeal arches

64
Q

CN X: Vagus nerve

Pharyngeal n….

● lies between ICA and IJV in neck

● contributes to pharyngeal plexus

● somatic motor to muscles of palate and pharynx (EXCEPT tensor veli palatini and stylopharyngeus)

A

CN X: Vagus nerve

External laryngeal n….

  • is a branch of superior laryngeal n.
  • somatic motor to cricothyroid m.
65
Q

CN X: Vagus nerve

Recurrent laryngeal n…

  • becomes inferior laryngeal n. after it pierces inferior pharyngeal constrictor m.
  • somatic motor to intrinsic laryngeal mm. EXCEPT cricothyroid
A

CN X: Vagus nerve

** Recurrent laryngeal n….**

  • sensory to infraglottic larynx + trachea + upper esophagus
66
Q

CN X: Vagus nerve

** Internal laryngeal n….**

● branch of superior laryngeal n.

● pierces thyrohyoid membrane

● sensory to supraglottic larynx

A

CN X: Vagus nerve

** Auricular n….**

▪ sensory to skin of external auditory meatus

Carotid n….

  • sensory to carotid body
67
Q

CN X: Vagus nerve

Pre-ganglionic parasympathetic innervation to…

● glands of larynx and pharynx

● upper esophagus and trachea

● all thoracic organs

● abdominal organs of foregut and midgut (up to left colic flexure)

A
68
Q

Anterior vagal trunk:

receives contribution from left vagus n.

on the anterior surface of esophagus

supplies stomach + liver + gallbladder + duodenum

A
69
Q

Posterior vagal trunk:

▪ receives contribution from right vagus n.

▪ on the posterior surface of esophagus

▪ innervates stomach + spleen + pancreas + small intestine + large intestine (up to left colic flexure)

A
70
Q

Intrinsic Laryngeal Muscles: Innervation

Recurrent laryngeal n. innervates which laryngeal mm.?

(5)

A

Posterior crico-arytenoid

Arytenoideus (transverse and oblique fibers)

Thyro-arytenoid

Vocalis

Lateral crico-arytenoid

71
Q

Intrinsic Laryngeal Muscles: Innervation

External laryngeal n. innervates which laryngeal m.?

(1)

A

Cricothyroid

72
Q

CN XI: Accessory nerve

- Exits cranial cavity through jugular foramen

  • Runs obliquely across the lateral aspect of neck
  • Motor innervation to sternocleidomastoid + trapezius mm.
  • Damage to CN XI → Paralysis of trapezius → Drooping tip of shoulder → Lateral shift of superior scapular angle (lateral “winged” scapula; most prominent during arm abduction)
A
73
Q

CN XII: Hypoglossal nerve

Exits cranial cavity through hypoglossal canal

  • Runs deep to digastric and stylohyoid mm.
  • Enters tongue medial to hyoglossus m.
  • Motor innervation to…

genioglossus

styloglossus

hyoglossus

intrinsic mm. (transverse + vertical + longitudinal fibers)

A

- Lesions of CN XII produce…

paralysis of tongue mm. that CN XII supplies → muscular atrophy on the affected side

deviation of protruded tongue to the paralyzed side

74
Q

Parasympathetic Innervation in Head

Oculomotor (CN III) –> Ciliary ganglion –>Constrictor pupillae + ciliary mm.

Lesser petrosal n. (CN IX) –> Otic ganglion –> Parotid gland

Greater petrosal n. (CN VII) –> Pterygopalatine ganglion –> Nasal + paranasal + palatal + lacrimal glands

Chorda tympani (CN VII) –> Submandibular ganglion –> Submandibular + sublingual glands

Vagus n. (CN X) –> Multiple ganglia in pharynx + larynx –> Mucous glands and blood vessels of pharynx + larynx

A

Sensory Innervation of Tongue

Posterior ⅓ of tongue (somatic + taste sensation):

● Glossopharyngeal n. (CN IX)

Anterior ⅔ of tongue (somatic sensation):

● Lingual n. (CN V3)

Anterior ⅔ of tongue (taste sensation):

● Chorda tympani (CN VII)

75
Q

Anatomy of Gag Reflex

A. Irritant in the mouth → Sensory information from oropharynx/soft palate/uvula/posterior tongue to brain via CN IX.

B. Elevation of soft palate by levator veli palatini (CN X).

C. Closure of glottis to protect lower respiratory airway (CN X).

D. Activation of pharyngeal constrictors to expel irritant object (CN X).

A

● sensory limb of gag reflex → CN IX

● motor limb of gag reflex → CN X

76
Q

Head and Neck: Sympathetic Innervation

Pre-ganglionic sympathetic innervation from…

● T1-T2 spinal cord segments

Pre-ganglionic sympathetic fibers synapse on…

● superior cervical ganglion

Post-ganglionic sympathetic fibers travel along with…

  • ECA and ICA (and their branches), and form…
  • external carotid plexus → vascular smooth muscles + arrector pili mm. + sweat glands + salivary glands + sebaceous glands
  • ** internal carotid plexus** → vascular smooth mm. + dilator pupillae m. + superior tarsal m. + ocular arterioles + lacrimal gland + nasal septum + lateral nasal wall + soft palate + hard palate (via branches of trigeminal n. or blood vessels)
A

Effects of sympathetic innervation on…

▪ ocular arterioles is vasoconstrictive → decrease in intraocular pressure

▪ cutaneous arterioles of face is vasodilatory (under conditions of thermal load or emotional state)

▪ cerebral arteries is vasoconstrictive

▪ sweat glands is secretory (under thermal load)

** gustatory sweating is stimulated by facial/glossopharyngeal nn., NOT by sympathetic nerves**

77
Q

Damage to sympathetic innervation of head: Horner’s syndrome

● paralysis of superior tarsal m. → mild ptosis (drooping) of upper eyelid

● paralysis of dilator pupillae m. → abnormal constriction (miosis) of pupil

● loss of heat-induced sweating

● loss of heat-induced/emotional vasodilation

A

Head and Neck: Sympathetic Innervation

1. Anatomy - BLOCK 4 (6 decks)

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