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Anatomy Final > Orbit II > Flashcards

Flashcards in Orbit II Deck (30)
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1
Q

Name the 4 rectus muscles of the eye

A
  • superior rectus
  • inferior rectus
  • lateral rectus
  • medial rectus
2
Q

Name the 2 oblique muscles of the eye

A
  • Superior oblique
  • Inferior oblique
3
Q

What makes up the common tendinous ring

A

Point of origin of 4 of the the muscles of the orbit

  • superior rectus
  • Inferior rectus
  • Lateral rectus
  • Medial rectus

encloses optic canal and superior orbital fissure

4
Q

What is the insertion and action of the levator palpebrae superioris muscle?

A
  • Insertion: superior tarsal plate
  • action: elevate upper eyelid
5
Q

What is the innervation of the Levator Palpebrae superioris m. and Superior rectus m.

A

Superior division of oculomotor (CN III)

6
Q

What nerve innervates lateral rectus m.

A

abducent (CN VI)

7
Q

What nerve innervates inferior rectus m. and medial rectus m.

A

inferior division of oculomotor (CN III)

8
Q

What nerve innervates the superior oblique m.

A

Trochlear (CN IV)

9
Q

What nerve innervates the inferior oblique m.

A

inferior division of oculomotor CN III

10
Q

What is the action of the medial rectus m.

A

STRONG adduction

11
Q

Action of lateral rectus

A

STRONG ABduction

12
Q

What is the action of the superior rectus m.

A

Strong elevation

Slight adduction

Intorsion

  • muscle lies at a angle from the medial wall of the orbit
13
Q

What is the action on inferior rectus m.

A
  • strong depression
  • slight adduction
  • extorsion
14
Q

What is the action of the superior oblique

A
  • strong depression
  • slight abduction
  • intorsion
15
Q

What is the action of the inferior oblique m.

A
  • strong elevation
  • slight abduction
  • extorsion
16
Q

intorsion vs extorsion

A

Rotation of upper cornea toward (intorsion) or away (Extorsion) from midline

17
Q

How can you test if a patient’s superior oblique m. is not functioning?

A

Have him/her adduct the eye (via medial rectus) and now superior oblique is a pure depressor

* inferior rectus cannot depress in this state; it now produces pure extorsion

18
Q

How can you check to see if superior rectus m. is functioning?

A

Have patient Abduct his/her eye (via lateral rectus); superior rectus is now a pure elevator

  • inferior oblique cannot elevate; it ow produces pure extorsion
19
Q

Name the two divisions of the oculomotor nerve (CN III).

A
  • Superior and Inferior division
20
Q

The superior division of oculomotor n (CN III) gives motor innervation to what 2 muscles?

A
  • superior rectus
  • Levator palpebrae superioris
21
Q

The inferior division supplies what (3 muscles) and has what type of innervation

A
  • medial rectus
  • inferior rectus
  • inferior oblique
  • motor; preganglionic parasympathetics
22
Q

How can you distinguish the trochlear nerve after it exits the superior orbital fissure

A

passes along the superior surface of the superior oblique muscle

23
Q

How can you distinguish the abducent nerve (CN VI) after it exits the superior orbital fissure

A

passes along the medial side of the lateral rectus muscle

24
Q

any nerve passing through the superior orbital fissure passes through what sinus

A

cavernous sinus

25
Q

Identify purple arrow

A

cavernous sinus

26
Q

identify blue

A

oculomotor (III)

27
Q

orange

A

Trochlear n ( CN IV)

28
Q

black

A

ophthalmic n. of trigeminal (CN V1)

29
Q

green

A

maxillary nerve of trigeminal (CN V2)

30
Q

identify

A

abducent nerve