Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
30 Cards in this Set
- Front
- Back
In an exophoric eye, light will fall on the _____ part of the retina but appears on the _____ part of the patient's visual field
|
temporal, nasal
|
|
-____ are monocular eye movements
-Both eyes moving in the same direction are called ___ -Both eyes moving in opposite directions are called _____ |
ductions, versions, vergences
|
|
The near triad consists of
|
Accomodation, convergence, and miosis
|
|
Increasing accomodation will ALWAYS cause an increase in
|
convergence and miosis
|
|
minus lenses ______ accomodation and plus lenses _____ accomodation
|
stimulate, relax
|
|
minus lenses ____ an exophore and ____ an esophore where as plus lenses do the opposite
|
reduce, increase
|
|
What is the purpose of Von Graefe phoria?
|
To measure subjectively the relative horizontal or vertical deviation of the eyes, one with respect to the other when fusion is interrupted using prisms
|
|
What are the prism specifications for Von Graefe phorias?
|
6^BD OD, 12^BI OS
|
|
When testing lateral phorias the patient should focus on the ______ target
|
upper
|
|
When testing vertical phorias the patient should focus on the _____ target
|
lower
|
|
What should you always ask the patient before beginning to test phorias?
|
Do you see 2 targets one up and one down?
|
|
-If patient is ortho the should see____
-If patient is 12 XP should see _____ -If patient is EP than should see______ -if patient is >12XP than will see _____ |
-one up and one down to the left
-one right on top of the other -more eso is created -one up and one down and to the right |
|
What are the instructions given when testing lateral phorias?
|
focus on the upper target and let me know when the other lines up like buttons on a shirt
|
|
Should the line of letters be vertical or horizontal when testing lateral phorias
|
vertical
|
|
What is the next step in measuring lateral phorias after verifying the patient sees two targets?
|
Decrease the BI prism until the two lines are vertically aligned
|
|
What do you record for lateral phorias?
|
magnitude and direction of the phoria
|
|
If BI than the patient is ___
If BO than the patient is ___ |
Exophoric
Esophoric |
|
What is the difference in Von Graefe phorias and the Flash technique?
|
When using the flash technique you occlude the eye with the measuring prism (OS)...remove the occluder briefly giving the patient the same instructions as before
|
|
What is the benefit of doing the Flash technique?
|
the patient has no opportunity to make fusional movements
|
|
What is the target for measuring vertical phorias?
|
a horizontal line of letters one line above BVA
|
|
What are the instructions for measuring vertical phorias once you verify the patient can see two lines?
|
Focus on the lower target and let me know when the upper target lines up like headlights on a car
|
|
Which prism do you change when measuring vertical phorias?
|
The BD prism
|
|
What do you record for vertical phorias?
|
magnitude and the hyper eye
EX: 1 R Hyper |
|
What are the similarities between measuring lateral and vertical phorias at distance?
|
Place the distance PD and the manifest in the phoropter in dim light
|
|
What are the similarities between measuring lateral and vertical phorias at near?
|
Place the near PD and the near correction in the phoropter in bright light with stand lamp
|
|
What is a difference between measuring near and distance phorias?
|
When measuring near phorias the patient could compensate the 12 BI before the test begins
|
|
If the patient can compensate for 12^BI than what is the next step?
|
Either increase the BI or make it 12^BO
|
|
What are some things that can be done if the patient only sees one image?
|
-check that both lens wells are open
-change magnitude of the prism -recheck PD |
|
What are some advantages to measuring phorias with Von Graefe?
|
-fine control of prism magnitude
-relatively quick -in phoropter makes it easier for the patient -can easily determine the gradient AC/A |
|
What are some of the disadvantages of Von Graefe phorias?
|
-less info than the cover test
-peripheral fusion is restricted due to phoropter -limited to primary gaze -depends on patient response b/c it is subjective |