Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Block 5 > Clinical: Von Graefe Phorias > Flashcards

Clinical: Von Graefe Phorias Flashcards

(51 cards)

Start Studying
1
Q

Phorometry is testing to assess…

A

Ocular alignement

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

Phorometry consists of various ways to…

A

Measure ocular alignment at different distances

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

Phorometry consists of various ways to…

A

Measure ocular alignment at different distances

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

Different tests used to test phorias:

A

-cover test
-hirschberg/krimsky
-Maddox rod
-modified thorington
-von graefe phorias

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

What is binocular vision?

A

The way the two eyes work together to integrate the images seen by each eye into one image

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

How does binocular vision work?

A

Each eye receives an image fo the object being viewed and the info is then sent to the brain where the images are then compared and processed into one image

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

To achieve binocular vision, retinal images must be:

A

-In good focus
-similar in size
-similar in shape
-aligned on the fovea of both eyes

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

Good binocular vision allows for us to have…

A

Single vision and good depth perception

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

An object will stimulate different parts of the retina if placed…

A

In different areas of the visual field

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

An object in the patients left visual field will stimulate:

A

-The nasal retina of the left eye
-the temporal retina of the right eye
**and vice versa

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

The right visual field projects to the…

A

Left visual cortex

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

The left visual field projects to the…

A

Right visual cortex

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

A visual target on one side of the visual field stimulates…

A

Certain points on the retina with respect to the fovea

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

The corresponding points help us…

A

Detect object location and direction

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

Heterotropia:

A

-A manifest deviation of the eye
-visual axes of both eyes do not intersect at a fixation point
-can result in diplopia or suppression of deviated eye

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

Heterophoria :

A

-tendency for the eyes to deviate away from bifocal fixation when fusion is broken

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

Esophoria

A

Posture of the eyes is inward

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

Exophoria

A

The posture of the eyes is outward

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

Hyperphoria

A

The posture of the eyes is upward

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

Hypophoria

A

The posture of the eye is downward (we never call anything a hypo, we refer to the opposite eye as a hyper instead)

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

Phorias can be related to:

Study These Flashcards
A

-abnormalities of binocular vision

22
Q

Patients need enough convergence and divergence ability to compensate for their phoria especially if they have…

Study These Flashcards
A

Symptoms of diplopia, eye strain, headaches, etc

23
Q

Patients should be able to maintain _____, ________ binocular vision

Study These Flashcards
A

Clear, comfortable

24
Q

In order for clear and comfortable binocular vision to occur:

Study These Flashcards
A

-retinal images must be aligned and on the fovea of each eye
-must be able to align their eyes and maintain alignment

25
Accommodative and alignment/vergence testing can aid in evaluating how…
A patients visual system is functioning day to day
26
Function of unilateral cover test
To distinguish between Phoria vs tropia
27
Function of alternating cover test
To determine direction and magnitude of the phoria
28
Von graefe phorias measures…
The presence, magnitude and direction of a phoria
29
Von graefe phorias are performed in the _____________
Phoropter
30
Von graefe is a ____________ measurement
Subjective
31
Von graefe phorias is performed after ___________ and uses prism to ___________ and ____________
Refraction, break fusion and measure deviation
32
Image bends towards the _____ in a prism
Apex
33
During Von graefe phorias, we use different prism over __________
BOTH eyes
34
Prism over one eye is used to _________________ and the other is used to _______________
Measure the phoria, dissociate the eyes
35
Distance lateral Von graefe phoria purpose:
To determine the relative horizontal position of the visual axes of the eyes at distance when fusion is broken
36
Distance lateral Von graefe phoria measures…
Horizontal heterophoria
37
Target for distance lateral Von graefe phoria:
Single letter two lines larger than the best corrected acuity in the worst seeing eye
38
What prims are used over each eye in distance lateral Von graefe phoria?
-12prism diopter BI OD (measure the prism = move) -6 prism diopter BU OS (dissociating prism = remain stationary)
39
How to direct patient when performing distance lateral Von graefe phoria?
-“you should see two letters, one up and to the right, and one down and to the left” -“look at the bottom letter and keep it clear” -“I will move the top letter from side to side. Let me know when it lines up directly above the bottom letter like buttons on a shirt”
40
To move the letters in a distance lateral Von graefe phoria test …
Gradually reduce the measuring prism (horizontal prism) until pt says they are aligned, go past that point and then go back towards the beginning point (12 pd BI) then average the two measurements if within 3pd of each other
41
What do you need to change when going from distance lateral phoria to near lateral phoria?
-put in tentative add if presbyopic -near wings in -near card at 40 cm -target is vertical line of isolated letters or single letter -bright illumination w/ stand lamp
42
If the patient only sees one target:
-pt could be suppressing (then can’t do test) -pt is fusion images together (increase the prism further or switch to BO)
43
If average of the two measurements is zero then….
The patient is ortho
44
Distance vertical Von graefe phoria purpose
Determine the vertical position of the visual axes of the eyes at distance when fusion is broken
45
For vertical prisms, what goes over which eye?
OD: 12 pd BI = dissociating prism OS: 6 pd BU = measuring prism
46
Use the same directions as the lateral phoria, but this time have pt focus on…
The top letter, tell pt to let you know when the letters line up side by side like headlights on a car
47
Near vertical phoria test target:
Horizontal line of letters or isolated single letter
48
Typical phoria test order:
-distance lateral phoria -distance vertical phoria -near lateral phorias -near vertical phorias
49
Expected phoria values for distance:
-1prism diopter XP (+/- 2pd) - 1EP to 3XP
50
Expected phoria values at near:
-3 prism diopters (+/-3pd) -ortho to 6XP
51
Important things to remember in Von graefe tests:
-instruct pt where to look during the test -always instruct pt to keep target clear to control accommodation -add more dissociating prism if target become clear during test

Block 5 (46 decks)

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