AOC AOC Binocular Vision and Strabismus 2

Question 1

Which type of strabismus is characterized by outward deviation of one or both eyes?

Accepted Answer

Exotropia

Answer

Exotropia refers to a manifest outward (divergent) deviation of one or both eyes.

Question 2

The alternate cover test primarily measures which type of deviation?

Accepted Answer

Total deviation including phoria and tropia

Answer

By alternately covering each eye and dissociating fusion, the alternate cover test reveals the total deviation (tropia plus phoria).

Question 3

Which surgical procedure on an extraocular muscle increases its effective length, thereby weakening its action?

Accepted Answer

Recession

Answer

A recession moves the muscle insertion posteriorly, lengthening its effective moment arm and reducing its pulling force.

Question 4

The Krimsky test estimates angle of deviation using which technique?

Accepted Answer

Placing prism before the deviating eye until corneal reflexes are symmetric

Answer

The Krimsky test places prisms before the deviating eye until the corneal light reflex is centered, providing an estimate of deviation.

Question 5

Stereopsis testing such as the Randot or Titmus fly test evaluates which visual function?

Accepted Answer

Binocular depth perception

Answer

Stereopsis tests measure binocular depth perception by presenting slightly disparate images to each eye requiring fusion.

(AOC) American Orthoptic Council Practice Test