midterm Flashcards

1
Q

in amblyopia, the best compensated visual acuity is _____ or worse in either or both eyes.

A

20/40

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

it is defined as a binocular or
monocular decrease in best corrected visual acuity (BCVA) due to pattern visual deprivation and/or abnormal binocular interaction during
visual immaturity for which there is no obvious ocular pathology or visual pathway defect and which in appropriate cases is reversible.

A

Amblyopia

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

Amblyopia is defined as a binocular or
monocular decrease in best corrected visual acuity (BCVA) due to _____________ during visual immaturity for which there is no obvious ocular pathology or visual pathway defect and which in appropriate cases is reversible (2)

A

-pattern visual deprivation
-abnormal binocular interaction

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

Before you diagnose a patient with amblyopia, make sure that he has no ocular __________(e.g. no glaucoma, no abnormalities during fundus or tumor, etc)

A

pathology

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

cause of amblyopia (1)

A

lack of proper eye development which results to Reduced Visual Acuity

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

meaning of:

lack of proper eye development which results to Reduced Visual Acuity

A

meaning something happened during the course of development. It may be during a critical period, at birth or 8-9 years old. there is a disease or an accident that may disrupt the proper development of the patient. It may lead to reduced visual acuity.

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

Categories of Amblyopia
(5)

A

-Strabismic Amblyopia
-Form Deprivation Amblyopia
-Anisometropia
-Isoametropia
-Refractive

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

types of form deprivation (3)

A

-Congenital Cataract
-Infantile Cataract
-ptosis

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

there is something that blocks the line of sight of the patient like congenital cataract or infantile cataract, or ptosis

A

Form Deprivation Amblyopia

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

when there is no input that can go inside the retina because the pupil is blocked

A

ptosis

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

unequal refractive error. usually you can consider if at least a 1.00D difference of right and left eye but if +1.00D, it doesn’t directly mean amblyopia, it must be
more than +1.00D

A

Anisometropia

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

chru or nope?

in anisometropia, If px is HYPEROPE: the patient is more prone to
develop amblyopia compared to Myope

A

chru.

ex: -5.00 and +5.00. Hyperope is more
prone to develop amblyopia compared to myope

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

approximately equal refractive error of both eyes but not necessarily equal
- ex: OD +5.25 and OS +5.00

A

Isoametropia

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

it is a type of amblyopia where in the higher the astigmatism, the higher the chance in developing amblyopia

A

Refractive

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

When both eyes are uncovered, both point towards the object of regard.

A

PHORIA

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

aka squint or tropia

A

STRABISMUS

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

chru or nope.

A strabismic patient does not perceive the world the same way, when the eye is turned, causing them to “suffer” from poor depth perception.

A

chru.

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

if a patient has strabismus, which of the 4 Circles of Skeffington is affected?

A
  • Anti-gravity and Centering (major problem)
  • Antigravity – answers the question WHERE AM I and where depth perception is concerned. So, if one eye is
    turned then depth perception.
  • Centering – answers the question WHERE IS IT, and where binocular vision is concerned. If the patient has strab then the patient has problems in centering and binocular vision.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

one eye is turned outwards, so if the
patient looks at the target, usually the target is placed BEHIND the real target.

Mismatch is present.

A

Exotropia

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

the target is perceived IN FRONT of the real target.

A

Esotropia

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

why is Brock string important?

A

Brock String is important because we can see how the patient localizes his space.

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

The patient cannot control his eyes due to: (5)

A

– POSTURE
– BALANCE
– CENTERING
– FIXATION
– IDENTIFICATION

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

the importance of centering (binocular vision) and anti gravity (depth perception) in strabismus

A

Binocular vision and depth perception are dependent upon visual development within these
2 circles. To accurately point both your eyes at an object, you must understand where you are and the distance between you and that object.

Not only are there interactions between all 4 circles, but experiencing depth perception will create feedback that enhances localization, centering, movement, and language.

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

chru or nope.

at 4 months of age, if the patient had fever or convulsions, there is a possibility that the patient may develop amblyopia or strabismus.

A

chru

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

how many months an infant develops binocular system?

A

4 months

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Prevalence of amblyopia and strabismus.

A
  • 4-6% of the population have amblyopia and/or strabismus.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

prevalence of eso deviation

A

Eso deviations occur far more frequently than exo deviations, with a prevalence ratio of approximately three to one (3:1)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Esodeviation is more common rather than exo because exo deviation is associated with _______ (kids are more eso than exo)

A

neurological insult

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Exo may be associated with _____ or _______

A

AV syndrome.
myasthenia gravis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

chru or nope.

There is no “critical period” in treating amblyopia and strabismus

A

chru.

We do not limit our patient in treating amblyopia and strab even if they’re in 30s, 40s, or 50s

however, there is a critical period in the development of amblyopia and strabismus at birth, or around 8-10 years old.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

etiology/causes of Strabismus (3)

A

Anatomical
Optical
Innervational

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

due to impairment of cranial nerves III, IV, VI, which represent the majority of cases.

A

Innervational
(Strabismus cause)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

refractive anisometropia, high RE, media opacities
- Optometrists can treat
- So if we identify that the patient’s strabismus is optical and we find out that he has a refractive error, we must first rule out the refractive error then we start from there

A

Optical –

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

abnormalities of EOM, ligaments, tendons, orbital contents.

optometrists must refer px to surgery

A

Anatomical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

types of innervational cause of strab/ambly:

A

Paresis
Paralysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

paresis vs paralysis

A

Paresis - EOM has movement but is weak; there is just an innervational problem
Paralysis - the nerve is dead and the EOMs wont work. Also, during un

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

EOM has movement but is weak; there is just an innervational problem

A

Paresis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

the nerve is dead and the EOMs wont work. Also, during uncover-cover, the eyes won’t move anymore

A

Paralysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

how to ensure that px eye muscles are not paralyzed?

A

perform cover tests and version tests.

before confirming that you can conduct vision rehabilitation for a strabismic patient, you must ensure that their eye muscles are not paralyzed by performing the tests above

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

chru or nope.

According to the Behavioral Optometry perspective, when strabismus is present, asymmetry in the body may be present.

A

chru.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

how to distinguish a person has strab/ambly by only seeing their body language? (4)

A

-Observe their gait (manner of walking)
-stance
-titled shoulders
-compensatory head movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Head Compensatory Movements (3)

A
  1. Face turn (either left or right) - horizontal deviation
  2. Chin elevation / depression - vertical deviation
  3. Head tilt to one shoulder (head tilt to right or left shoulder) - torsional deviation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

a patient is right eso.

During primary gaze, the patient sees diplopia. To compensate, the px turns his head towards?

A

towards the right.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

If a patient has hypertropia, which head compensatory movement is done?

A

chin depression is done

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

right movement of the head

A

eso OD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

the socket cannot hold the whole bone so the tendency is there is displacement.

A

Hip dysplasia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

the socket cannot hold the whole
bone so the tendency is there is displacement.

A

Hip dysplasia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

patient may possibly lead in developing
amblyopia or strabismus because the normal development of px disrupted

Case 1: Born with incomplete hip development was put into a body cast for much of the first several months of life. Came in as a constant OD ET with a –6.00 in the OD and +0.50 OS. Afraid of driving off the right side of the road.

What are the problems?

A
  1. There is a problem in depth perception.
  2. The px has right esotropia
    - the patient has no awareness of the right side of the road
  3. There is a difference in the refractive error, the patient has antimetropia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

is a condition in which one eye is myopic, while the fellow eye is hyperopic

A

Antimetropia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Born with incomplete hip development was put into a body cast for much of the first several months of life. Came in as a constant OD ET with a –6.00 in the OD and +0.50 OS. Afraid of driving off
the right side of the road.

Is there a difference in the image perceived by the patient between his right and left eyes?

A

Yes. However, the +0.50D doesn’t have an effect but the minus power (-6.00D) has an effect as it minifies the space
or image perceived. Thus, the patient’s space is more compressed. Px’s space is more compressed due to
- refractive error of high myopia in OD
- right esotropia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

which method enables space compression?

A

MOTOR EQUIVALENCE
or CHALKBOARD CIRCLES.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

procedure and materials for space compression

A

Materials: chalkboard and two chalks

Procedure: Have the patient look at the target and allow him to draw circles on his sides.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

result for space compression

A

Result: Supposedly, the circles must somehow be symmetrical. If there is a big difference in the drawn circle, possibly, the patient has space
compression.

52
Q

each eye is directed towards a
different object. it occurs when the images of the two different objects compete to be represented on the Internal representation of reality for the same location in space at the
same time

A

Confusion

53
Q

Through, _______, we can understand the idea of superimposed images

A

Cheiroscope

54
Q

the eyes deviate nasally. The right eye
will view the smiley while the left eye sees the sun. If different images are seen, in the retina, it will be _______ (leading to visual confusion).

A

superimposed

55
Q

Resolving Confusion:
The visual system/person can resolve confusion in several ways: (4)

A
  1. Tune one channel out. Suppression (generally only portions of one channel of flow is tuned out).
  2. Physically cover an eye.
    - usually we see this in kids when they have visual confusion, they squint or cover one eye
  3. Blur one channel. Develop single sided refractive conditions
  4. Turn one eye in a different direction (increase deviation to remove confusion)
56
Q

what type of revolving confusion is this?

OD and OS sees confusion (at first OU
is plano). Now the brain is confused with the images it perceives, so what it does is to ______ . At first small changes but eventually, the power increases until one eye is blur and only the
other eye sees to prevent confusion

A

blur one channel

57
Q

it is a condition in which the amblyopic patient does not use the central foveal area under.

looking with the line of sight away from the fovea in an otherwise healthy eye.

Esotropia - nasal EF // Hyper - down EF

Exotropia - temporal EF // Hypo - up EF

A

Eccentric Fixation (monocular)

58
Q

under monocular conditions

A

Eccentric

59
Q

under binocular condition

A

Anomalous Retinal Correspondence -

60
Q

Eccentric Fixation falls on: (4)

A
  1. Parafoveal – around the fovea
  2. Macular
  3. Paramacular – around the macula
  4. Peripheral
61
Q

the person uses a point near the fovea to look with due to a loss of vision. The loss can be optical, retinal, or neurological.

A

Eccentric viewing

62
Q

This can be seen with an ophthalmoscope using the grid.

A

eccentric fixation

63
Q

-procedure to test for Eccentric Fixation

A
  • performed through the same procedures of ophthalmoscopy
  • you can occlude the amblyopic eye first and then later on, test the amblyopic eye
  • direct and dim illumination
  • After focusing on the patient’s fundus, ask the patient to look at the target center and identify the location of the grid
64
Q

Sensory adaptation which allows strabismic patients to use both eyes without diplopia or confusion

A

Anomalous Retinal Correspondence

65
Q

Angle of squint is small and the extrafoveal point is close to the fovea – to regain the binocular advantage, although anomalous

A

Anomalous/ Abnormal Retinal Correspondence

66
Q

This results in the eye seeing binocularly single in spite of a manifest squint.

A

Anomalous/ Abnormal Retinal Correspondence

67
Q

Under binocular conditions the fovea and the extrafoveal

A

Anomalous/ Abnormal Retinal Correspondence

68
Q

ARC is common with _____(if deviation is less than 10 ∆D)

A

microstrabismus

69
Q

ARC is common with microstrabismus, if deviation is:

A

less than 10 ∆D

70
Q

NRC WITHOUT STRAB

A

single image

71
Q

A 5-year-old px has strabismus, at that time, usually there is still normal retinal correspondence, so she sees double image. Years later, about 20 years old, so it is now a long-standing strabismus, most likely the patient’s visual system has adapted and has now ARC. Therefore, he now sees a single image

Is ARC okay in the optometrist perspective?

A

ARC is okay for the px because he can see a single image. But, ARC in the perspective of an optometrist, is not okay because this is temporary.

The stereopsis and depth perception are sacrificed in this situation.

72
Q

Situation: Px w/ High Strab + No ARC
For example, a patient during the prism cover test has more than 50 ∆D (which is the largest value in the loose prism diopter) but there is still slight
movement. During W4D, she only sees 2 red dots.

assess.

A
  • She has no ARC but she just suppressed it because the deviation is too big
73
Q

Situation: Px w/ ARC + Microstrabismus

how to assess.

A

When you are dealing with microstrabismus with ARC (but they see single image), you must be careful in VT because there is a tendency that the px sees double.

For us, this is okay because it is slowly going back to NRC. But for these patients, it is not okay because they already know how to see single image, then you VT them, and now they’re seeing double vision again.. It is important to inform the patient of
what he will encounter.

74
Q

TIPS

❖ ARC - Be careful with your VT plan

A

<3

75
Q

Let’s say the target is the X, under binocular conditions, when both eyes are pointed towards the object, the image perceived by px must be projected in the right central fovea and left central fovea

A

Target @ Center

76
Q

Device to assess eccentric fixation

A

Visuoscopy

77
Q

NRC WITH STRAB (normal retinal correspondence)

A

double image

78
Q

ARC WITH (long-standing) STRAB

A

single image

79
Q

Usually confirmed with an ophthalmoscope in the case of retinal or optical pathology, but may need further testing in other cases.

A

eccentric viewing

80
Q

usually we see this in kids when they have visual confusion, they squint or cover one eye

A

Physically cover an eye.

81
Q

When an eye is covered the eye moves out of alignment and when uncovered, alignment is quickly restored

A

phoria

82
Q

both eyes are looking at the target, at Right Nasal Retina and Left Temporal Retina.

A

Target @ right side of space

83
Q

Corresponding means

A

the correct pairing.

84
Q

Fovea stimulated should be right temporal retinal and left nasal fovea (it changes depending on where the target is located).

A

Target @ left side of space

85
Q

it is when, without eye turn, both eyes are pointing directly at the object. The patient sees the single target

A

Normal retinal correspondence

86
Q

means the eyes are correctly positioned, with both eyes looking in the same direction, with no eye turn.

A

Normal retinal correspondence (NRC)

87
Q

When both eyes are open and uncovered, one eye is pointed at the target and the other eye is pointed somewhere else

A

strabismus

88
Q

As optometrists, our only management is to

A

correct EOR but VT, not anymore.

89
Q

Microstrabismus + ARC = are very well-adapted, if they have no problem, they do not need VT.

A

chru

90
Q

Microstrabismus + ARC + no chief complaint + normal saccades + normal pursuits + no omission/skipping of words = usually NO VT and no need to prescribe VT

A

chru

91
Q

You can observe body language of a patient with strab/ambly through: (3)

A

-during visual acuity tests
-during refraction
-preliminary tests

92
Q

left movement of the head

A

exo OD

93
Q

chin depression

A

hyper

94
Q

chin elevation

A

hypo

95
Q

the eyes deviate nasally. The right eye
will view the smiley while the left eye sees the sun.

If different images are seen, in the retina, it will be superimposed leading to:

A

visual confusion

96
Q

When both the fovea have a common visual direction and the retinal elements nasal to the fovea in one eye corresponds to the retina, elements temporal to the fovea in the other eye.

A

Normal Retinal Correspondence

97
Q

Optic Disc is always located
towards the:

A

nose or nasally

98
Q

yellow part in the fundus is called

A

foveal reflex

99
Q

the patient has eccentric fixation
because if you are an amblyope, you have a problem in the central vision (so reduced VA because VA is associated with central vision).
That is why he is not using the central fovea as fixation. He looks for an area in the fovea as fixation

A

amblyopic px does not use central vision

Found in amblyopes and strabismic amblyopes

100
Q

Every line in the “grid” is equivalent to a prism diopter, and can be____ per line.

A

1 or 2 prism diopters

101
Q

person perceives 2 objects as occupying the same location in visual space

A

visual confusion

102
Q

When fovea of one eye has a common visual direction with an extrafoveal area in the other eye

A

ARC

103
Q

In _____, the central part of the retina of each eye, known as the fovea, is correctly positioned and sees the images the person is looking at.

A

NRC

104
Q

In NRC, the central part of the retina of each eye, known as the ______, is correctly positioned and sees the images the person is looking at.

A

fovea

105
Q

what is amblyopia?

A

Amblyopia is defined as a binocular or monocular decrease in best corrected visual acuity (BCVA) due to pattern visual deprivation and abnormal binocular interaction during visual immaturity which there’s no obvious ocular pathology or visual pathway defect, which in appropriate cases is reversible

106
Q

in hip dysplasia, the socket cannot hold the whole bone so the tendency is there is:

A

displacement

107
Q

Patients with ARC lessens the_________. It is challenging for VT.

A

prognosis

108
Q

generally only portions of one channel of flow is tuned out

A

Tune one channel out. Suppression

109
Q

Develop single sided refractive conditions

A

Blur one channel

110
Q

horizontal deviation. (which movement)

A

face turn (either left or right)

111
Q

vertical deviation (which movement)

A

Chin elevation / depression

112
Q

torsional deviation (which movement)

A

Head tilt to one shoulder (head tilt to right or left shoulder)

113
Q

This law states that the yoke muscle receives equal and simultaneous innervation

A

Herring’s

114
Q

This law states that contraction of a muscle is accompanied by relaxation of antagonist

A

Sherrington’s

115
Q

If medial rectus contracts, the ____ relaxes

A

Lateral

116
Q

If inferior rectus contracts, the _____ relaxes

A

Superior rectus

117
Q

Give at least 2 causes of ambly

A

Anisometropia
Starbismic amblyopia

118
Q

Equal size of retinal image

A

Iseikonia

119
Q

When both eyes are open and uncovered, one eye is pointed at the target and the other eye is pointed somewhere else

A

Strabismus

120
Q

If the patient has OD esotropia, he might adapt by turning his head towards the (r/l)?

A

Right (eso OD)

121
Q

Synergist muscle during dextroversion

A

LIO RSO LIR LSR

122
Q

Synergist muscle during levoversion

A

RSR RLR LIO LSO

123
Q

Using an opque ocluder in unilateral cover test, the examiner observed outward movement of the uncovered left eye. The patient may have?

A

Exotropia

124
Q

Using translucent occluder in unilateral cover test, the examiner observed no movement on the uncovered eye and an outward movement of the covered eye as seen through the occluder. The patient may have?

A

Exophoria

125
Q

Using an opaque occluder, the examiner observed upward movement of uncovered eye, the patient may have?

A

Hypertropia

126
Q

As the person looks in lower position of gaze, the eso deviation is larger

A

V syndrome esotropia

127
Q

As the person looks in lower position of gaze, the eso deviation is less

A

A syndrome esotropia

128
Q

The patient with strabismus will perceived the image as _____ if he has normal retinal correspondence

A

Double

129
Q

Chin elevation and depression is seen in patient with what type of deviation?

A

Vertical