Evaluating the Deviation Flashcards
If a patient has a wide bridge of nose, how will the esotropia look vs. exotropia?
esotropia = looks worse exotropia = looks better
If patient has a narrow bridge of nose, how will the ET look vs. XT?
ET = looks better XT = looks worse
If patient has epitcanthal folds, how will the ET look vs. XT?
ET = looks worse XT = looks better
If px has a small IPD, how will the ET vs. XT look?
ET = worse XT = better
If px has a large IPD, how will the ET vs. XT look?
ET = better XT = worse
If px has a wide face, how will the ET vs. XT look?
ET = worse XT = better
If px has a narrow face,, how will the ET vs. XT look?
ET = better XT = worse
If a px has high hyperopia, they are most likely to be ET or XT?
ET
If a px has anisometropia and astigmatism, they are most likely to be ET or XT?
XT
What are the anatomical etiologies of strabismus?
- EOM abnormalities
- Abnormal content of orbit
- Abnormal ligaments/tendons
Ocular disease may cause younger children to have (ET/XT) and older children/adults to have (ET/XT)?
young = ET older = XT
What test can be used to evaluate the alignment objectively?
- Cover test
2. Hirschberg
This objective alignment test is good for young patients who don’t cooperate.
Hirschberg
Angle Kappa is measured under (monocular/binocular) conditions.
Monocular conditions
When performing the krimsky test, which eye is prism placed over?
The deviating eye
- increase prism until pupil reflex is symmetrical with normal eye
When performing unilateral CT, which eye should we be covering?
Fixating eye
T/F: For the simultaneous prism cover test (SPCT), you place the CT over fixating eye and prism over deviated eye at same time.
True
- add prism until there’s no movelemt
During ACT, if you have a patient who is neutral on different prism magnitudes, what should you record?
The highest neutral reading
This the amount of deviation when the normal eye is fixating in primary gaze.
Primary Angle of deviation
This is the amount of deviation when the paretic eye is fixating i primary gaze.
Secondary Angle of deviation
- if non-paretic, mag will be same as primary
- if paretic, mag will be the same as primary
ACT = 15Δ ET
Visuoscopy = 5Δ of nasal EF
What is the true angle of deviation?
T = M + EF T = +15pd + (+5pd) T = 20pd
ACT = Ortho
Visuoscopy = 3Δ nasal EF
What’s the true angle of deviation?
T = M + EF
T = 0 + (+3pd)
T = 3pd
- Microtropia w/ identitiy
T/F: When stacking prism, stacking horizontal and vertical prisms is ok.
True
When performing ACT at distance, using a shorter room will cause what 2 things to happen?
- decrease mag of XT
2. Increase mag of ET
If a patient wears lenses that are +/- 5.00D, what will plus lenses vs. minus lenses do to measured angle of deviation?
+ = decrease angle of dev.
- = increase angle of dev
How do you hold prism to minimize prism rotation and power changes?
Hold it in frontal plane position
This type of vertical deviation is present when the eyes are straight.
Primary
This type of vertical deviation is present when the ares are deviated (strabismic); common in XTs.
Secondary
