Cranial Nerves 3 Flashcards Preview

MD4001 WEEK 2 > Cranial Nerves 3 > Flashcards

Flashcards in Cranial Nerves 3 Deck (29)
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1
Q

What is the function of the trigeminal CN V nerve?

A

PRIMARY:
Sensation: Head & Cavities (general somatic afferent)
Motor: Muscles of Mastication (special visceral efferent)

ADDITIONAL:
CARRIER of Autonomic Fibres Parasympathetic (general visceral efferent) Anterior 2/3 Taste/Gustation (special visceral afferent)

2
Q

What is the function of CN VII Facial & Nervus Intermedius?

A

PRIMARY:
Motor: Muscles of Facial Expression (special visceral efferent)

ADDITIONAL:
Parasympathetic (general visceral efferent) Anterior 2/3 Taste/Gustation (special visceral afferent)

3
Q

What are the modalities of CN V?

A
  • General Somatic Afferent to the mesencephalic, chief sensory & spinal nuclei in the midbrain, pons & medulla oblongata
  • Special Visceral Efferent from the motor nucleus in the pons to the muscles of mastication (derived from 1st pharyngeal arch)
4
Q

State the brainstem nuclei associated with the trigeminal CN V nerve?

A
  • CN V motor nucleus to muscles of mastication
  • CN V sensory nuclei
  • CN V mesencephalic nucleus for proprioception
  • CN V chief sensory nucleus for discriminative touch
  • CN V spinal nucleus for pain & temperature for structures supplied by CN V as well as general conscious sensation for the viscera supplied by CN IX & X

SEE SLIDE

5
Q

What are the modalities of CN VII plus Nervus Intermedius?

A
  • General Visceral Efferent (parasympathetic) from the superior salivatory nucleus in the pons to the lacrimal gland, nasal & oral cavities (mucous membranes), sinuses, submandibular & sublingual salivary glands
  • Special Visceral Afferent to the solitary nucleus in the medulla oblongata receiving taste from the anterior 2/3 of the tongue (via the chorda tympani nerve)
6
Q

State the brainstem nuclei associated with the CN VII plus Nervus Intermedius.

A
  • CN VII motor nucleus to muscles of facial expression
  • CN VII solitary nucleus
  • CN VII superior salivatory nucleus with parasympathetic secretomotor to lacrimal gland, nasal & oral cavities, submandibular & sublingual salivary glands
  • CN VII (also CN IX & X) solitary nucleus for taste & visceral sensation
7
Q

What is the pathway of the greater petrosal nerve?

A
  1. Greater petrosal nerve escapes from the middle ear & lies on the surface of the petrous temporal bone in the middle cranial fossa
  2. Greater petrosal nerve passes through the foramen lacerum & heads towards the pterygoid canal
8
Q

What does the greater petrosal nerve from the Nervus Intermedius of CN VII carry?

A

Carries general visceral efferent (parasympathetic secretomotor) fibres that contribute to the innervation of the lacrimal gland & special visceral afferent (gustation/taste) fibres from the palate

9
Q

What of the greater and deep petrosal nerves combine as?

A

The nerve of the pterygoid canal

10
Q

Where does the pterygoidpalatine fossa lie?

A

Lies just lateral to the upper aspect of the nasal cavity & nasopharynx behind the orbit & above the hard/soft palate

11
Q

How does the trigeminal nerve get parasympathetic fibres?

A
  • Preganglionic parasympathetic fibres from the nervus intermedius of CN VII via the greater petrosal & nerve of pterygoid canal synapse in the pterygopalatine ganglion that is within the pterygopalatine fossa
  • Postganglionic fibres hitch- hike with branches of CN V2 & some branches of CN V1
12
Q

Describe the lacrimal glands innervation.

A
  1. CN V2 carrying postganglionic parasympathetic fibres from the pterygopalatine ganglion gives a zygomatic branch after entering the orbit via the inferior orbital fissure
  2. The zygomatic gives the zygomaticotemporal that sends a branch to join the lacrimal branch of CN V1
13
Q

What does the lacrimal nerve carry?

A

The lacrimal nerve from CN V1 carries parasympathetic secretomotor fibres from the pterygopalatine ganglion to the lacrimal gland

14
Q

What supplies the frontal sinus?

A

The supraorbital nerve

15
Q

What supplies the ethmoid sinuses, lateral wall of the nasal cavity and the nasal septum?

A

Anterior ethmoidal nerve with posterior ethmoidal nerve behind it

16
Q

What passes through the cribriform plate?

A

Olfactory nerves & anterior ethmoidal nerve

17
Q

Where is the sphenopalatine foramen and what passes through it?

A

Medial to the pterygopalatine fossa for the passage of artery (sphenopalatine) & branches of CN V2 (nasopalatine)

18
Q

What passes through the incisive canal?

A

The nasopalatine nerve passes to the anterior aspect of the palate & terminal branches of the greater palatine artery enter the nasal cavity

19
Q

Describe the innervation of the lateral wall of the nasal cavity.

A
  • Anterior, superior, (lateral) supplied by nasal nerves from CN V1 mainly via the anterior ethmoidal nerve
  • Posterior, inferior, (lateral) supplied by nasal nerves from CN V2 mainly via the greater palatine nerve
20
Q

Where does the greater palatine nerve and artery pass?

A

Greater palatine nerve & artery pass inferiorly in the palatine canal lateral to the nasal cavity

21
Q

What nerve innervates the tip of the nose?

A

Anterior ethmoidal nerve continues as the external nasal nerve that supplies the tip of the nose

22
Q

Describe the innervation of the medial wall and septum of the nasal cavity.

A
  • Posterior, inferior, (medial) nasal nerves from CN V2 mainly via the nasopalatine nerve (that enters the nasal cavity via the sphenopalatine foramen)
    CN V2 branches are accompanied by branches of the maxillary branch of the external carotid artery
  • Anterior, superior, (medial) nasal nerves from CN V1
    CN V1 branches are accompanied by branches of the ophthalmic branch of the internal carotid artery
23
Q

What supplies the hard and soft palates?

A

Greater & lesser palatine branches of CN V2 (plus secretomotor from the pterygopalatine ganglion) supply the hard & soft palates respectively with an addition from the nasopalatine nerve anteriorly

24
Q

What supplies the sphenoidal sinuses?

A

Both CN V1 and V2

25
Q

What supplies the teeth & gums supply the maxillary sinus?

A

The infraorbital nerve along with the superior alveolar nerves (anterior, middle & posterior)

26
Q

What is the course of the chorda tympani nerve pass?

A
  • Chorda tympani arising from CN VII nervus intermedius just before the stylomastoid foramen
  • The chorda tympani nerve passes anteriorly through the middle ear between the incus & malleus just medial to the tympanic membrane
  • Chorda tympani nerve emerges through the petrotympanic fissure to join the lingual nerve of V3 in the infratemporal fossa just below the foramen oval
27
Q

What information does the lingual nerve carry?

A
  • General somatic sensation
    from anterior 2/3 of tongue, floor of mouth mucosa & mandibular lingual gum
  • Carrier of general visceral efferent (parasympathetic secretomotor) to sublingual & submandibular glands
  • Carrier of special visceral afferent for taste of anterior 2/3 of tongue via chorda tympani nerve (CN VII nervus intermedius)
28
Q

What is the course of the lingual nerve (CN V3)?

A
  1. The lingual nerve (CN V3) enters the oral cavity between the mylohyoid & hyoglossus, it lies lateral to the submandibular duct then passes inferior to the duct to ascend into the tongue on its medial side
  2. Preganglionic parasympathetic fibres leave the lingual nerve & synapse in the submandibular ganglion
  3. Postganglionic branches pass to the submandibular & sublingual salivary glands
29
Q

What innervates the lower teeth and skin of chin and lower lip?

A

Inferior alveolar (dental) nerve to lower teeth emerging as mental nerve to skin of chin & lower lip (both skin & mucous membranes)