CN III and V Flashcards by SN K

What are the CN that carry autonomic fibres

3, 7, 9, 10

How well did you know this?

Not at all

Perfectly

List the eye muscles supplied by CN III

Medical rectus

Superior rectus

Inferior rectus

Inferior oblique

* Levator Palpebrae Superioris

How well did you know this?

Not at all

Perfectly

What 2 eye muscles are not supplied by CN III?

SO4 LR6 !!!

How well did you know this?

Not at all

Perfectly

Label the image below

A: CN III
B: Big Optic Nerve
C: CN III
D: CN IV
E: CN VI

How well did you know this?

Not at all

Perfectly

List one nerve and artery which pass through the optic canal

Optic nerve and opthalmic artery

How well did you know this?

Not at all

Perfectly

List 4 nerves that pass through the Superior orbital fissure (incl specific branches)

1) Occulomotor nerve- superior and inferior division (III)
2) Trochlear nerve (IV)
3) V1: Trigeminal nerve (frontal, lacrimal and nasocillary branches)
4) Abducens VI

How well did you know this?

Not at all

Perfectly

List one vein that passes through the superior orbital fissure

Superior Opthalmic vein

How well did you know this?

Not at all

Perfectly

What cranial nerve passes through the Inferior orbital fissue? (incl what 2 branches specifically)

Trigeminal nerve V2: the zygomatic and infraorbital branches

How well did you know this?

Not at all

Perfectly

What vein passes through the inferior orbital fissue?

Inferior opthalmic vein

How well did you know this?

Not at all

Perfectly

Autonomic fibres of CN III come from the _________ nucleus.

This nucleus gives rise to preganglionic PNS fibres which travel to the _________ ganglion located in the _________.

Here they synapse with post-ganglionic PNS fibers which travel to the eye via _________ nerves to supply the_________ which flattens the lens for _________ and the _________ to constrict the pupil.

Edinger-Westphal, cillary, orbit, short ciliary, ciliary muscle, accomidation, Iris

How well did you know this?

Not at all

Perfectly

The cillary ganglion is located between the _________ and _________

optic nerve and lateral rectus muscle

How well did you know this?

Not at all

Perfectly

Do the motor and PNS fibres of CN III exit togther or seperate?

CN III (motor + parasympathetic fibres) exit together as one structure from brainstem

How well did you know this?

Not at all

Perfectly

Describe the pathway of CN III as it leaves the brainstem (motor and PNS)

CN III (motor + parasympathetic fibres) exit together as one structure from brainstem:

1) Travel anteriorly
2) Runs along lateral wall of cavernous sinus to superior orbital fissure
3) CN III enters the orbit to innervate the extraocular eyeball muscles and levator palpebrae superioris
4) Parasympathetic fibres peel OFF and go to the ciliary ganglion

How well did you know this?

Not at all

Perfectly

List 4 things that would be seen in a CN 3 palsy and explain why

1) Ptosis ➞ due to paralysis of LPS
2) Diplopia (double vision) + ‘down and out eye’ ➞ due to unopposed action of SO4 and LO6 muscles
3) Dilation of pupil (Blown pupil/Mydriasis)

due to loss of pupil constriction (action of the SNS fibres unopposed)
absent pupillary light reflex

4) Loss of accommodation (can’t converge to focus close up) ➞ due to paralysis of ciliary muscles

How well did you know this?

Not at all

Perfectly

What is the sensory and motor supply of the Trigeminal nerve

Sensory: to most of the head and face, sensory to mucous membranes of mouth, nose, paranasal airsinuses

Motor: to muscles of mastication

How well did you know this?

Not at all

Perfectly

Which of the trigeminal nerve branches is the largest?

Mandibular division (V3)

How well did you know this?

Not at all

Perfectly

What 4 autonomic ganglia are associated with CN V and what does this mean?

Ciliary (III)

Pterygopalatine (VII)

Submandibular (VII)

Otic (IV)

Autonmic cranial nerves 3,7,9 and 10 join up and hitchhike on branches of CN V

How well did you know this?

Not at all

Perfectly

Give the ‘Preganglionic ➞ Synapse ➞ Post-ganglionic’ structure for each autonomic ganglion

III ➞ ciliary ganglion ➞ Iris (contriction of pupil) and ciliary muscle (accomidation)

VII ➞ pterygopalatine ganglion ➞ lacrimal gland (tears)

VII ➞ submandibular ganglion ➞ SM and SL salivary gland

IX ➞ otic ganglion ➞ parotid salivary gland

X ➞➞➞ synapse on target organ: heart etc… rest and digest

How well did you know this?

Not at all

Perfectly

Which is the only branch of the trigeminal nerve that has motor?

All have sensory, only V3 has motor

What is the MMA a branch off?

Through what hole does it exit the cranial cavity?

MMA is a branch of the maxillary artery which is a branch of the ECA

Exits cranial cavity via the Foramen spinosum

Describe the pathway of V1: ophthalmic division of the Trigeminal nerve

1) From the Trigeminal ganglion, V1 passes through cavernous sinus
2) V1 Leaves the skull via the superior orbital fissure ➞ then divides into THREE branches (frontal, lacrimal, nasocillary)
3) The nasocillary branch travels to the ciliary ganglion (pics up some autonomic fibres)
4) Collectivly these innervate the dura of anterior cranial fossa, skin of forehead, upper eyelid, eye, cornea and most of nose

What are the 3 branches that V1 gives off and what does each supply?

On which branchs do autonomics hitchhike?

1) frontal: gives off branches to supply eyelid and scalp
2) lacrimal: branches to lacrimal gland, eyelid and eye
* autonomics hitchhike to lacrimal gland along this branch
3) nasocillary: branches to eyelid, eye, cornea, conjunctivae, mucosae of skin and nose
* gives off branch to ciliary ganglion for autonomics to hitchhike to eye

What is the afferent and efferent branch of the corneal reflex?

The AFFERENT branch (sensory) of the corneal reflex is conveyed by V1 ➞ nasociliary branch

The EFFERENT branch (motor) is conveyed by CN VII

Describe the pathway of V2: maxillary division of the Trigeminal nerve

1) Leaves the skull via foramen rotundum
2) Emerges into the Pterygopalatine Fossa and gives off branches to the Pterygopalatine Ganglion
3) Continues through Inferior Orbital Fissure as the Infra-orbital nerve which supplies skin of cheek and lower eye

Besides the 'Infra-orbital nerve' give 4 other branches V2 gives off

1) Meningeal branch 2) Zygomatic nerve 3) Posterior Superior Alveolar nerve 4) Numerous branches going to and then coming OFF the Pterygopalatine ganglion

What does the V2 branch of the trigeminal nerve supply?

Sensory to: midface, palate, paranasal sinuses, maxillary teeth, cranial dura

What reflex is mediated by the V2 branch of the trigeminal nerve? (maxillary nerve)

Mediates the afferent limb of sneeze reflex (irritation of nasal mucosa) \* Vagus nerve does the efferent limb

What is the sensory supply of V3 (mandibular branch) of the trigeminal nerve?

Skin of the temporal region Part of Ear Lower face Sensation to anterior 2/3rds of tongue (Remember: CNVII does TASTE here) Floor of mouth

What is the motor supply of V3 (mandibular branch) of the trigeminal nerve?

Muscles of Mastication

What autonomic fibres hitchhike on V3 (mandibular branch) of the trigeminal nerve

PNS CNVII fibres on chorda tympani hitchhike on the lingual nerve (branch of V3) to salivary glands

Describe the pathway of V3 (mandibular division) of the Trigeminal nerve

1) Exits skull via foramen ovale 2) Reaches Infratemporal Fossa and divides into anterior and posterior trunk 3) Gives off branches to the Otic Ganglion

What does V3 divide into within the infratemporal fossa and what is the supply of each?

1) Anterior Trunk: sensory to inner cheek and Motor to FOUR muscles of mastication 2) Posterior Trunk: sensory skin of temple, ear, tongue, teeth and a small motor component Anterior trunk contains the MOTOR fibres

What is the specific sensory branch of V3: anterior trunk?

Buccal nerve: supplies inner cheek and mucous membrane

What are the 4 muscles of mastication supplied by V3: anterior trunk? (motor innervation) List the function of each

1) Masseter muscle - ELEVATES 2) Temporalis muscle - ELEVATES and RETRACTS 3) Lateral Pterygoid muscles - PROTRUSION and Side to Side 4) Medial Pterygoid muscles - ELEVATION and Side to Side

How does the Posterior Trunk of V3 furthur divide? Are these branches sensory or motor?

1) Auriculotemporal nerve 2) Lingual nerve 3) Inferior alveolar nerve All MOSTLY Sensory EXCEPT a small part of the Inferior alveolar nerve

Give 3 treatments for Trigeminal Neuralgia

1) Anticonvulsant Carbamazepine (or Gabapentin for pain) 2) Microvascular Decompression 3) Ablative stereotactic radiosurgery

What is the sensory innervation of the auriculotemporal nerve?

Sensory to skin of temple and auricle

PNS pre-ganglionic fibres from the glossopharyngeal synaps on the _______ ganglion. Here post-ganglionic fibres hitchhike with a branch of _______ known as the _______ nerve to reach the parotid gland for salivary production

otic, V3, auriculotemporal

How may the Auriculotemporal nerve be damaged and what is the specific condition that may result

Can be damaged during surgery of the parotid which can result in Frey's syndrome: This is when the nerve heals but reattachs to sweat glands instead of the original salivary gland. This means when the person eats, talks or thinks about food they sweat instead of salivating

Give 2 symptoms of Freys syndrome

1) Sweating while eating (gustatory sweating) in the region of the parotid gland, temple cheek and upper neck 2) Facial flushing while eating

What is the sensory innervation of the Lingual nerve? Which autonomic ganglion does it provide branches too?

Passes down to side of tongue and supplies sensation to mucous membranes on the floor of the mouth and sensation (NOT taste) to anterior 2/3rd of tongue Gives off branches to the Submandibular Ganglion

What is the sensory innervation of the Inferior Alveolar nerve? What branch does it give off and what does this supply

Passes down into the mandibular canal and supplies teeth of lower jaw Gives off the Mental nerve which emerges from the mental foramen to supply sensation to gums of lower jaw, skin of chin and lower lip

What motor branch does the Inferior Alveolar nerve give off and what does this supply?

Passes down into the mandibular canal and give off the 'nerve to Mylohyoid' which supplies the mylohoid muscle and anterior belly of the digastric muscle

What resides in the mandibular canal? What will a fracture of the mandible (loss of this nerve) result in?

Inferior alveolar nerve: loss of this nerve will result in numbness in the teeth (good for dentistry...)

What would damage to the ENTIRE Trigeminal nerve result in?

Ipsilateral numbness of the face, anterior scalp, auricle, mucous membranes of nose/mouth, anterior 2/3rds of tongue Paralysis and wasting of ipsilateral muscles of mastication \*\* Pain is frequently referred from one area to another in this nerve

How do we test motor innervation of the Trigeminal nerve?

Clenching jaw muscles and jaw jerk reflex

What is Trigeminal Neuralgia?

Excruciating neuropathic pain along the course of CN V. Gives rise to acute, lancinating, episodic pain over specific distribution Cause is unknown but may be trigger factors sich as touching skin Pain so bad it is known as the 'Suicide Disease'