Abv 1 - Lecture 1 - Intro To Abv

Front 1

What is a LATENT deviation of the eyes?

It is only detected when patient is ___________.

What is another name for it?

Back 1

Phoria

dissociated

“Latent Neuromuscular Bias”

Front 2

A tendency for the eyes to drift INWARD is known as what?

With this condition, what kind of movement is detected in uncovered eye on the UNILATERAL cover test?

With this condition, what kind of movement is detected in uncovered eye on the ALTERNATING cover test?

Back 2

ESOphoria

UNILATERAL = No movement

ALTERNATING = Outward

Front 3

With an ESOphoria, patients will have a tendency to localize objects ___________.

Back 3

Closer

Front 4

___________ helps overcome ESOphoria or else you get
___________ (Complete breakdown of binocular system).

___________ also helps because it reduces the amount of ESOphoria in the system.

Back 4

Negative Fusional Vergences (NFV) = Divergence = Relaxation of Accommodation

Diplopia

Relaxation of Accommodation

Front 5

A tendency for the eyes to drift OUTWARD is known as what?

With this condition, what kind of movement is detected in uncovered eye on the UNILATERAL cover test?

With this condition, what kind of movement is detected in uncovered eye on the ALTERNATING cover test?

Back 5

EXOphoria

UNILATERAL = No movement

ALTERNATING = INward

Front 6

___________ helps overcome ESOphoria or else you get
___________ (Complete breakdown of binocular system).

___________ also helps because it reduces the amount of EXOphoria in the system.

Back 6

Positive Fusional Vergences (PFV) = Convergence = Stimulation of accommodation

Diplopia

Stimulation of accommodation

Front 7

EXOphoria patients will have a tendency to localize objects ___________.

Back 7

Further away

Front 8

While an abnormal amount of deviation (in or out) is kept under control by
the ___________ and ___________ system, it is done so at a cost to the
patient (blur, fatigue, eyestrain, diplopia, etc.)

Back 8

Accommodative and Vergence

Front 9

Unilateral Cover Test (UCT) tests for what?

Another name for this condition?

Give 2 definitions for this condition.

Back 9

Tropia

Strabismus

• MANIFEST Deviation of the eyes
• Breakdown of the binocular system

Front 10

What kind of target must be used for UCT?

Back 10

Accomodative

Front 11

During UCT, if inward movement is seen (turned eye moves to pick
up fixation), then patient has an ____________.

Back 11

EXOTROPIA

Front 12

During UCT, if an outward movement is seen (turned eye movespick up fixation), then patient has an ____________.

Back 12

ESOTROPIA

Front 13

Never let the patient regain fusion during the
____________.

If the patient is allowed to fuse, you will never uncover the ____________ or ____________ deviation of
the eyes.

Back 13

Alternating Cover Test

Phoria

Latent

Front 14

What prism is used to neutralize

EXO

ESO

Back 14

EXO = BI

ESO = BO


Put the BASE in the direction of the movement.

Front 15

Expected findings for the cover tests have not yet been
studied specifically but clinically, expecteds for ____________ are used (See Morganʼs Norms)

Back 15

Von Graefe phorias

Front 16

YOU NEED TO CONTROLL ACCOMMODATION ALWAYS
ALWAYS ALWAYS! in which tests?

Back 16

1) Covert Test
2) Von Graefe Phoria Measurement

Front 17

Cover test is performed with ____________ in place.

Back 17

Habitual Rx

Front 18

What should be set in the phoropter for Von Graefe Phoria?

What are the prisms set to?

Back 18

Habitual Rx in phoropter
OS = 6BD
OD = 12BI (15BI for near)

Measuring prism is the one you are moving.


There can be different combinations of
the above set up. Just remember that it
is important to dissociate the patient
to cause the eyes to go to their resting
position or phoria

Front 19

How should you instruct the patient when performing Von Graefe Phoria?

Back 19

“Keep looking at this target and make sure you keep it clear.”

Front 20

Record the results under the Vertical Phoria area on the patient chart.

- Always record the ____________ eye.

- A BD measurement over the OS indicates an ____________ hyper.

- A BU measurement over the OS indicates an ____________ hyper.

Back 20

Hyper

OS

OD

Front 21

Maddox Rod (Maddox over OS in Example)

o ESO Deviation
 ___________ Diplopia
 Eye rests ___________
 Image projects on ___________ retinal relative to the opposite eye
 Therefore brain projects image on the ___________ side as deviated eye (___________)

o Exo Deviation
 ___________ Diplopia
 Eye rest ___________
 Image projects on ___________ retinal relative to the opposite eye

 Therefore brain projects image on the ___________ side as deviated eye (___________)

Back 21

Maddox Rod (Maddox over OS in Example)

o ESO Deviation
 UNCROSSED Diplopia
 Eye rests IN
 Image projects on NASAL retinal relative to the opposite eye
 Therefore brain projects image on the SAME side as
deviated eye (UNCROSSED)

o Exo Deviation
 CROSSED Diplopia
 Eye rest OUT
 Image projects on TEMPORAL retinal relative to the opposite eye
 Therefore brain projects image on the OPPOSITE side as deviated eye (CROSSED)

Front 22

Which test is used to determine fusional vergences?

What are fusional vergences?

Explain what happens during the test.

Back 22

Smooth Vergence Testing in the Phoropter

Fusional Vergence - Vergence movements used to resolve retinal disparity of an image

In the case of Smooth Vergence Testing
BI - images fall on NASAL retina - eyes DIVERGE to get it back on the fovea

BO - image falls on TEMPORAL retina - eye CONVERGE to get it back on the fovea

Front 23

During Smooth Vergence testing, what aspect of vision is remaining stationary?

How is the target kept clear?

What is being measure up until the blur point?

Back 23

The plane of accommodation must remain stationary.

Accommodation must be stimulated or relaxed depending on what vergence demand is presented.

For BI - eyes DIVERGE and the CA/C link wants accommodation to RELAX but to keep the target clear accommodation must STIMULATE (PRA).


For BO - eyes CONVERGE and the CA/C link wants accommodation to STIMULATE but to keep the target clear accommodation must RELAX (NRA).

Positive/Negative Relative Fusional Vergence

Front 24

When does the blur occur during Smooth Vergence Testing?

When does the break occur?

Back 24

When accommodation can no longer counteract the tendency to move with vergence the blur occurs.

The break occurs when vergence can no longer keep the target single.

Front 25

What are the instructions given during Smooth Vergence Testing?

Back 25

Blur - Break - Recovery

Front 26

What do you test first during Smooth Vergence Testing?

Back 26

BI/NRV before BO/PRV

Front 27

What are the expected values of the NPC

for schoolchildren?

for adults?

Back 27

Schoolchildren - 6 cm break

Adults - 5/7 cm break

Front 28

What is the purpose of the BCC?

What is another name for it?

Why use a cross cylinder?

Why dim the lights?

What would the target look like at the endpoint?

Back 28

Used to determine the "posture" of accommodation

Fused Cross-Cylinder

(-) in one direction and (+) in another direction, inducing myopia and hyperopia

Dimming the lights minimizes the DEPTH OF FOCUS by minimizing the effect of pupil size

The lines look the same

Front 29

For BCC, how much should you add over the manifest to fog?

If they say the vertical lines are more blurry what do you add?

If they say the horizontal lines are more blurry, what do you add?

Back 29

+ 2.00 <-- Vertical lines should be darker but if they are note just keep adding (+)

Vertical lines add MINUS

Horizontal lines add PLUS

Front 30

What are the expected values for the BCC in non-presbyopes?

Which group of individuals is this test best suited for?

What is an alternative to the BCC in particular patients?

Back 30

+0.25 to +0.75

BCC is best suited for presbyobes

The MEM is best suited for non-presbyopes

Front 31

TQ: What is a good definition for NRA/PRA?

What is another way to say this - the purpose of the test?

Back 31

The ability of accommodation to RELAX and STIMULATE under the vergence system.

Used to figure out a patient's ADD as well as patients range of accommodation under the influence of the binocular system (vergence).

The NRA/PRA changes accommodative response WITHOUT changing vergence demand.

Front 32

What can the NRA be used to do?

Back 32

NRA can be used to detect if a patient is over-minused.

Adding (+) lenses so if they have a HIGH NRA, may be an indication they were over-minused.

Front 33

For NRA/PRA, what is the instruction given to the patient regarding the target?

What would you consider your Relative Point?

Back 33

Keep the target CLEAR and SINGLE

The lenses that the PRA or NRA was recorded through (Manifest or BCC)

Front 34

For NRA, by adding plus lenses in front of the eyes, accommodation does what?

While this is occurring, what are the eyes doing to maintain ocular alignment on a non-moving target?

Back 34

Relaxes

Positive Relative Vergence

Front 35

Define Relative Vergence.

Back 35

Relative Vergence - Fusional Vergence that is measured independent from the accommodative system (this type of vergence is trying to couteract the Accommodation - Convergence link)

Front 36

For PRA, by adding minus lenses in front of the eyes, accommodation does what?

While this is occurring, what are the eyes doing to maintain ocular alignment on a non-moving target?

Back 36

Stimulate accommodation

Negative Relative Vergence

Front 37

The NRA/PRA indirectly measures what?

Back 37

Relative Vergence

Front 38

If an emmetropic eye had a power of 60 D,

What is the accommodative demand of an object at 50 cm?

What about for a hyperope with 58 D to start?

What about for a myope with 62 D initially?

Back 38

Accommodative demand = 1/.50 = 2 D

Emmetrope = 62 D

Hyperopes must exert 4 D come to a total 58 + 4 = 62 D

Myope will not accommodate at all to see the target because it is already at the far point

Front 39

How much does an uncorrected 2.50 D hyperopes accommodate at 40 cm?

How much does an uncorrected 2.50 D myope accommodate at 40 cm?

Back 39

Hyperope accommodates 5 D

Myope accommodates 0

Front 40

What are Hofstetter's Equations?

Back 40

Minimum Amplitude = 15 - (0.25 X age)



Mean Amplitude = 18.5 - (0.3 X age)



Maximum Amplitude = 25 - (0.4 X age)

Front 41

What does Donder's Push Up technique measure?

TQ: How is performed?

What is another way this test can be performed?

Back 41

Amplitude of Accommodation

Monocular

Pull Away Method

Front 42

What all do you record for Donder's Push Up?

Back 42

1) Method - Push Up or Pull Away

2) Near point card size and print used

3) Linear distance of sustained blur (cm)

4) Dioptric measurement

Front 43

How do you obtain the amplitude in diopters from the Minus Lens to Blur Test?

Example: First sustained blur at - 6.00 D over the manifest at a target 40 cm away. What would the amplitude be?

Back 43

To obtain the amplitude in D, add - 2.50 D (working distance) to the amount of minus added

- 6.00 + - 2.50 = - 8.50

Front 44

Which method of measuring amplitude yields a lower result?

Why is this?

What is a suggested way to fix this discrepancy?

Back 44

Minus Lens To Blur yields a lower amplitude compared to Donder's.

This is due to spectacle minification.

Changing the test distance to 33 cm instead of 40 cm but still using 2.50 in the calculation (we will use a 40 cm test distance)

Front 45

What is the patient's ability to relax and stimulate the accommodative system called?

What part of accommodation does this test examine?

Back 45

Facility

Dynamics

Front 46

What is a pure measure of the accommodative system?

What does a poor performance on this test suggest?

Back 46

Monocular Accommodative Facility (MAF)

An accommodative problem only

Front 47

What is a measure of the accommodative system with influence of the binocular system?

What else MUST you perform with this test?

What does a poor performance on this test suggest?

Back 47

Binocular Accommodative Facility (BAF)

An accommodative problem or binocular problem

A SUPPRESSION check

Front 48

What are the three ways we can come up with AC/A ratio?

Back 48

1) Calculated

2) Gradient

3) Logic

Front 49

What three elements of stereo testing are included in the Randot Testing Book?

Back 49

1) Suppression Check (R + L)

2) Wirt Circles - Contain monocular cues

3) Global Stereopsis

Front 50

Wirt Circles are an example of what type of stereopsis?

Random Dot Forms are an example of what type of stereopsis?

Back 50

Wirt - Local

Random Dot - Global

Front 51

TQ: What is a requirement for patient's during a global stereo test?

Back 51

Patient must be BIFOVEAL to see the targets

Front 52

Suppression in the non - strabismic can happen because why?

Back 52

1) Adaptation to minimize stress - "Fusional Stress"

2) Central Retina (5 degrees)

3) Anisometropia - unequal image sizes where the images cannot be fused

Front 53

What to types of suppression in the non - strabismic are there?

What is the difference in the two?

Which one is more symptomatic?

Back 53

1) Constant

Central retina is constantly non-functional and there is complete adaptation

2) Intermittent

There is an ON and OFF switch for central vision. Creates visual confusion while reading and contributes to poor saccades and fixation.

Intermitted suppression is more symptomatic.

Front 54

What are the expect values for the NRA and PRA?

Back 54

NRA - +2.00 +/- 0.50

PRA - - 2.37 +/- 1.00