Question
Following test is used to diagnose which ocular condition as shown in image:
A. Strabismus
B. Heterophoria
C. Both A & C
D. None of the above
Show Answer
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Correct Answer » C Explanation |
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Answer. C. Both A & C
Given image is cover-uncover test
- The cover-uncover test to diagnose various types of tropias, which is a medical term for strabismus.
- The single cover test is a test is used to determine if there is a heterotropia or tropia, which is a manifest strabismus or misalignment that is always present.
- The first eye is covered for approximately 1-2 seconds. As this eye is covered, the uncovered eye is observed for any shift in fixation.
- The cross-cover test, or alternating cover test is usually employed to detect heterophoria.
- One eye is covered, and then the cover is moved immediately over to the other eye. With heterophoria, when the cover is moved to the other eye, the eye that has just been uncovered can be seen to move from a deviated point.
- The difference between heterotropia and heterophoria can be easily understood as follows.
- With heterotropia, a correcting movement of the eye can be detected already by the simple cover test; with heterophoria, such correcting movement only takes place in the cross-cover test.
- People with heterophoria are able to create and maintain binocular fusion through vergence, and the cross-cover test purposely breaks this fusion, making the latent misalignment visible.
