Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

272A > L18 Innervation of the Eye > Flashcards

L18 Innervation of the Eye Flashcards

1
Q

What are the 3 types of nerves?

A

Sensory, motor, autonomic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are cranial nerves?

A

Nerves that originate in thebrain, and innervate the head, neck, and upper trunk
Nuclei in the brain stem
12 pairs of nerves from 1-12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Which CN are important for vision?

A

CN2-7 (6 pairs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

List the names for each cranial nerve important for vision?

A

2 - optic nerve
3 - oculomotor nerve
4 - trochlear
5 - trigeminal
6 - Abducent
7 - Facial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Where does the ophthalmic branch (of CNV) innervate/branch out to?

A

Eye (pretty much all components) –> lacrimal glands, ends outside orbit, conjunctiva, mucous membrane of nasal cavity, skin of eyelids, eyebrows, forehead, and nose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Where do all the nerves enter the orbital area from?

A

Sphenoid bone through the superior or inferior fissure, then through the Annulus of Zinn. While, some nerves pass through the fissures but not the Annulus of Zinn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the significance of nerves that are above the ring (Annulus of Zinn)?

A

Free to move

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the significance of nerves that pass through the ring (Annulus of Zinn)?

A

Cannot move around

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What happens when there is inflammation in the area of Annulus of Zinn?

A

Compression of structures within it –> compression of optic nerve –> impair vision

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which nerves branch off from the trigeminal nerve (CNV)?

A

NVa - ophthalmic
NVb - maxillary
NVc - mandibular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which nerves branch off NVa ophthalmic branch?

A

Lacrimal, nasociliary, frontal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Some nerves pass through near the walls of the Cavernous sinus of sphenoid bone, and some through the middle. Which nerves pass through where?

A

Walls: 3,4,5
Middle: 6 and internal carotid artery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which nerves in the carvernous sinus are more likely to be damaged?

A

Nerves located closer to the sphenoid bones (in the cavernous sinus) are more likely to be damaged.

Thus, those near the walls - 3,4,5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the order of nerves in the orbit from top to bottom?

A

Lacrimal (NVa) > frontal (NVa) > trochlear (NIV) > Sup III > nasociliary> inf III > abducent (NVI).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Which nerves are above the ring?

A

Lacrimal, frontal, trochlear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Which nerves are in the ring?

A

Sup III, nasociliary III, abducent

17
Q

Which nerve is the only nerve to exit the orbit?

A

CN2

18
Q

Which intraocular muscles does CN3 innervate?

A

Iris (sphincter pupillae), ciliary muscle (accommodation) via parasympathetic nerve fibres

19
Q

What else does CN3 innervate?

A

LPS (levator palpabrae superioris) - upper eyelid for blinking

20
Q

What is the path of CN3?

A

Originates in the brainstem and passes through wall of c.sinus, above NIV. Then runs with sensory branch NVa and divide into superior and inferior branches within superior orbital fissure and Annulus of Zinn.

21
Q

What does the superior division of CN3 innervate?

A

SR, levator palpebrae superioris

22
Q

What does the inferior division of CN3 innervate?

A

Divides into three branches to supply the MR, IR, IO.

23
Q

The nerve to inferior oblique gives rise to a thick branch (containing parasympathetic nerve fibres) which passes to the…

A

Ciliary ganglion.

24
Q

What is the ciliary ganglion?

A

Short ciliary nerves which supply the ciliary muscle and sphincter pupillae.

25
Q

What does CNIV innervate?

A

Supplies the SO muscle.

26
Q

What nerve is the thinnest of cranial nerves?

A

NIV.

27
Q

What is the pathway of NIV?

A

Leaves brainstem from dorsal (posterior) surface, wall of c.sinus below NIII above NV. Pass through superior orbital fissure above the tendinous ring.

28
Q

What does the abducen (IV) supply?

A

LR muscle.

29
Q

What is the pathway of the abducens nerve?

A

Originate in brainstem below NIII and NIV. Pass through the middle of c.sinus. Passes through the Annulus of Zinn.

30
Q

Why is CNIV most affected ocular motor nerve in adults?

A

Could be due to its long trajectory (longest trajectory intracranially)

31
Q

What are the two branches of the frontal branch?

A

Supraorbital, supratrochlear.

32
Q

What are the branches of the nasociliary branch?

A

Long ciliary nerves for iris and cornea.

33
Q

What nerve is commonly affected in diabetes?

A

NVI as it is the longest course through brain, sign of poor or untreated diabetes, resolves after treatment.

34
Q

What are other signs of nerve abnormality?

A

Ptosis, pupil defects, sensation changes to face.

35
Q

Where can abnormality in nerves occur?

A

Level of brain stem, course though brain cavernous sinus or within orbit.

272A (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions