EOMs, eye movement & facial muscles

Question 1

What are the involuntary intrinsic muscles of the globe?

Answer 1

-ciliary
- iris sphincter
-iris dilator

Question 2

What are the extrinsic muscles?

Answer 2

• superior rectus
• inferior rectus
• medial rectus
• lateral rectus
• superior rectus
• inferior oblique
• levator palpebrae superioris

Question 3

What is the x axis?

Answer 3

medial to lateral (nasal to temporal, horizontal )

Question 4

What is the y axis?

Answer 4

anterior to posterior (sagittal)

Question 5

What is the z axis?

Answer 5

superior to inferior

Question 6

whats adduction?

Answer 6

towards the nose

Question 7

whats abduction?

Answer 7

away from the nose

Question 8

What are rotates that can occur around the horizontal axis?

Answer 8

elevation and depression

Question 9

What are torsions/cyclorotations?

Answer 9

rotations around the sagittal axis

Question 10

whats intorsion/incyclorotation?

Answer 10

rotation nasally

Question 11

whats extorsion/excyclorotation?

Answer 11

rotation temporally

Question 12

Whats vergence?

Answer 12

eyes move in opposite directions i.e convergence, divergence

Question 13

what is versions?

Answer 13

eyes move in the same direction i.e levoversion (left gaze)
dextroversion (right gaze)
supraverison (elevated)
infraversion (depressed)

Question 14

what is primary gaze?

Answer 14

position of the eyes when head is erect and the eyes are focused for infinity

Question 15

What is secondary positions of gaze?

Answer 15

rotations around either the vertical or horizontal axis

Question 16

What is tertiary positions of gaze?

Answer 16

rotations around both the vertical and horizontal axes

Question 17

what is Duane’s isolated agonist model?

Answer 17

during eye movements all 6 extraocular muscles are in some state of contraction or relaxation

Question 18

what is the primary action of the medial and lateral rectus?

Answer 18

medial rectus - adduction
lateral rectus = abduction

Question 19

What is the primary action of the superior and inferior rectus?

Answer 19

superior rectus = elevation
inferior rectus = depression

Question 20

Whats the primary action of the superior and inferior oblique?

Answer 20

superior oblique = intorsion
inferior oblique= extorsion

Question 21

What are the secondary actions of the superior rectus?

Answer 21

adduction and intorsion

Question 22

What are the secondary actions of the inferior rectus?

Answer 22

adduction and extorsion

Question 23

What are the secondary actions of the superior oblique?

Answer 23

depression and abduction

Question 24

What are the secondary actions of the inferior oblique?

Answer 24

elevation and abduction

Question 25

what degree can only vertical movement occur of the SR and IR?

Answer 25

23 degrees

Question 26

What degrees can we isolate the oblique muscles (the other vertical movers in addition to SR & IR)?

Answer 26

51-55 degrees

Question 27

which cranial nerve controls the actions of the superior oblique muscle?

Answer 27

cranial nerve 4

Question 28

which muscles produce eyebrow movements? where do they originate and insert?

Answer 28

• frontalis
• procerus
• corrugator superciliaris
• obicularis oculi
  originate from bone or fascia and insert into the skin

Question 29

what cranial nerve are all muscles innervated by?

Answer 29

Crainal nerve VII (7)

Question 30

frontalis muscle specifically___?

Answer 30

elevates the eyebrow

Question 31

corrugator superciliaris specifically__? & origin, inserts?

Answer 31

moves the eyebrow medially and downward
origin: frontal bone
inserts: skin near the eyebrows

Question 32

procerus specifically ___? & origin, insertion?

Answer 32

pulls the medial portion of the eyebrow inferiorly
origin: nasal bone
inserts: into frontalis muscle

Question 33

What is the depressor supercilii? & origin, insertion?

Answer 33

pulls the procerus inferior and lateral
origin: lacrimal bone
inserts : lateral side of procerus