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Flashcards in Extraocular muscles Deck (21):
1

Name the 7 extra ocular muscles

Medial rectus (MR)
Lateral rectus (LR)
Superior rectus (SR)
Inferior rectus (IR)
Superior oblique (SO)
Inferior oblique (IO)
Levator palpebrae superioris (LPS)

2

Rectus muscles - origination and attachment

Originate - common tendinous ring
Attach - sclera

3

What is the name of the tendon of SO ?

Trochlea

4

What is the function of LPS?

Elevates the upper eyelid

5

Which CN innervates the LR?

CN VI (abducent)

6

Which CN innervates the SO?

CN IV (trochlear)
- think sulphate (SO4)

7

Which muscles does CN III innervate?

MR, IO, SR, IR, LPS

8

When clinically testing the eye, movements occur from the 'primary position'. Describe this

Gaze directed forward
face forward
eyes forward
looking straight ahead

9

How do you test individual muscles?

Make sure that the plane of the muscle is matched up with the gaze of the eyeball

10

Which 2 muscles are involved in elevation of the eyeball?

Superior rectus
Inferior oblique

11

Which 2 muscles are involved in depression of the eyeball

Inferior rectus
Superior oblique

12

What is the function of LR?

Abducts the eyeball

13

What is the function of MR?

Adducts the eyeball

14

How do you test SR muscle?

Must first abduct the eye (LR)
- LR brings the eyeball gaze into the same plane as SR and IR
- get patient to look up

15

SR eye movement

Patient looks out and up

16

how do you test IR muscle?

Must first abduct the eye (LR)
- LR brings the eyeball gaze into the same plane as SR and IR
- get patient to look down

17

IR eye movement

Patient looks out and down

18

How do you test SO?

Must first adduct the eye (MR)
- MR brings the eyeball gaze into the same plane as SO and IO
- get patient to look down

19

SO eye movement

Patient looks in and down

20

How do you test IO?

Must first adduct the eye (MR)
- MR brings the eyeball gaze into the same plane as SO and IO
- get patient to look up

21

IO eye movements

Patient looks in and up