Exotropia Flashcards
Are most XTs constant or intermittent?
Intermittent
- rarely constant and unilateral
Infantile XT are usually constant with an angle > 30pd. When does it onset?
2-4 mo of age
T/F: Infantile XTs have a large prevalence of underlying systemic of neurological disease?
True
This type of constant XT is caused by a severe loss of vision in one eye; uncorrected aniso, cataract, macular lesion or retinoblastoma.
Sensory XT - large angle, constant, unilateral XT
This type of constant XT is found after surgery for a large ET or after correction with glasses.
Consecutive XT
Any XT over __ mo is abnormal.
6 mo
What type of XT will close one eye in bright sunlight?
IXT
- 50% of pxs squint in sunlight
Basic Exotropia patients may have good stereoacuity but poor what?
Poor 1’ and 2’ fusion
- check W4D
What are the 3 main triggers for DE XT?
- Inattention
- Fatigue
- Illness
When trying to determine if a px is a True vs. Simulated DE, you can patch them. What do the results show?
Sim = near deviation increases True = near deviation stays the same
When trying to determine if a px is a True vs. Simulated DE, you do the +300 lens CT. What do the results show?
Sim = no change in near angle True = near angle equals or exceeds distance angle
Co-variation is very common in IXT. How is it dx?
HBAIT
- determine correspondence when eyes are aligned
- determine correspondence when eyes are turned
For an IXT, if the eye is turned out more than 50% of the time, what’s the control score?
4
For an IXT, if the eye is turned out less than 50% of the time, what’s the control score?
3
If no XT is observed unless dissociated with recover in > 5sec, what’s the control score?
2
