Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Motility > 9-Ocular Motility > Flashcards

9-Ocular Motility Flashcards

(70 cards)

Start Studying
1
Q

Primary position of the eyes

A

Eyes fixate straight ahead and eyes and head are straight

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

Secondary position

A

Around the X ad Z axes of Fick. Purely vertical or horizontal

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

Tertiary position

A

Y axis and head tilt positions

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

How many cardinal positions do we have

A

6

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

What are cardinal positions

A

Positions where only 1 muscle in each eye is responsible for movement

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

What is the field of action

A

The gaze where the effect of a muscle is best observed

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

Any weakness of the SO can be seen as what

A

Depression in adduction

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

Why I’d the field of action important

A

Is helps you isolate if a deviation seen is weakness of that muscle, a restriction of action from the antagonist, or both

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

What is agonist antagonist of motility

A

Pair of muscles in the SAME eye that move in opposite direction

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

What are synergistic muscles

A

Muscles in the SAME eye that move in the SAME direction

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

What are yoke muscles

A

Pair of muscles, one in each eye, the produce conjugate eye movements (move eye in same direction)

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

What is the Sherrington law of reciprocal innervation

A

Increased innervation to on e muscle is accompanied by a decrease innervation to its antagonist in the same eye

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

What is the hering law of equal innervation

A

During conjugate eye movements, equal and simultaneous innervation flow to yoked muscles

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

Due to Herings law of equal innervation what will you see if there is a palsy in one muscle

A

The yoke muscle in the other eye will over react

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

What muscles are important for horizontal versions

A

Vertical rectus muscles and oblique muscles

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

What muscles are important for vertical versions

A

Horizontal rectus muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Primary deviation

A

Unaffected eye fixates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Secondary deviation:

A

Restricted eye fixates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which is bigger a primary or secondary deviation?

A

Secondary, because there is increased innervation to move the affected eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

T/F Increase innervation goes to the non-fixating eye that causes excessive action and a larger deviation

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Ductions

A

Movement of one eye sound the axes of Fick

Monocular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Versions

A

Binocular

Simultaneous and conjugate eye movements or rotation of both eyes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are conjugate eye movements

A

Both eyes move in the same direction and same amount

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Vergences are

A

Disconjugate eye movements where the eyes rotate or move in opposite directions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What are vergences important for
Fusion
26
Convergence
Both eyes rotate in
27
Divergence
Both eyes rotate out
28
Incyclovergence
Rotation of the superior portion of the eyes in
29
Excyclovergence is
Rotation of superior portion of both eyes out
30
T/F versions and vergences have similar late cites?
True
31
Which is faster acting movements? Versions or vergences?
Versions are faster
32
What is the infranuclear control
Cranial nerves (3,4,5) and the muscles they innervate
33
What is nuclear control
The cranial nuclei
34
What is Supranuclear control
Higher order sensory and motor system that plans and controls eye movements Cerebral cortex, cerebellum, brainstem
35
What control system controls versions and vergences?
Supranuclear
36
What eye movements are included in versions?
``` Saccades Pursuits VOR OKN OKR ```
37
What are saccades?
Fast conjugate eye movements that work to keep images on the fovea. They require a strong force
38
What is the latency for saccades?
120-200 ms
39
When are saccades developed
1 year of age
40
Are saccades voluntary?
Yes, but they can be reflexive
41
What are pursuits?
Following eye movements
42
What is the latency for pursuits
125 ms
43
What is the peak velocity for pursuits
30-60 degrees per sec
44
What do pursuits match up
Eye velocity to target velocity
45
Are pursuits voluntary or involuntary
Involuntary
46
When do pursuits develop
3-4 months of life
47
What controls pursuits
Parietal lobe on same side
48
What are vestibule-ocular reflex (VOR)
Movements that stabilize a retinal image during brief head movements
49
What can the VOR be seen in
Dolls head maneuver
50
When do VOR develop
Horizontal at birth | Vertical is later
51
What is seen on dolls head maneuver (eye movement)
Eye moves opposite of head movement
52
What causes horizontal nystagmus
Vestibular damage
53
When is dolls head maneuver contraindicated
In trauma where spinal/cervical injuries
54
What is the caloric test? How does the eye move with different temperature water
Test that uses warm and cold water to set up a temperature gradient in the semicircular canals. Cold water the eye moves to opposite ear. Warm water it moves toward the same ear that water was injected in. COWS
55
What is OKR responsible for
Continuous eye movements. It kicks in after VOR response fades with continuous head movements
56
What is rotational testing? What does it show?
Spin patient in a chair for about 20 seconds. Eyes will move in fast phase in opposite direction of rotation
57
What is OKN
Slow pursuit eye movement followed by fast corrective saccades. The head is still. It requires inpu from the visual system. Has a longer latency
58
When is OKN developed
3-5 months
59
When is OKN used
In malingering, and cooperative patients
60
What does a + OKN tell you
That VA is at or better than the size of the stripes on OKN drum
61
What does a - OKN tell you
Nothing
62
How is OKN tested
With an OKN drum. Horizontal and vertical
63
Slide 33
Big chart
64
What do vergences ensure
Bifoveal fusion
65
What is fusional vergences
It requires the attention and cooperation of the cerebral cortex
66
What is tonic vergence
Constant innervaton tone to the EOMs when awake and alert. To keep the eyes straight forward because the eyes are naturally diverging.
67
What is proximal vergences
Induced due to awareness of near
68
What are accommodative vergences
Consistent increment of accommodative convergence with each dipter of accommodation gives AC/A ratio
69
What does a high AC/A produce
ET with accommodation
70
What dies a low AC/A do
Makes it harder to converge, less esotropic, more exotropic

Motility (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions