Cover Test

Question 1

What information can you glean from a cover test?

Answer 1

1) Near & Distance
Tells you if difference in deviation at distance

2) With & Without Glasses
Whether there’s an accommodative element to the deviation

3) Manifest or Latent or Manifest with Latent Component
(report if able to take up fixation or not using manifest eye and diplopia in manifest. Report recovery in latent deviations on how controlled it is. If intermittent it gives you info on how controlled it is like how easily it becomes manifest and how symptomatic such ad diplopia)

4) Abnormal head posture (AHP) or not

5) If there is an accommodative element or not to light or target.

6) Size and direction of deviation

Question 2

What do you report in a manifest deviation?

Answer 2

Eye of deviation and if diplopia is present (c for with and s for without)

Question 3

What do you report in a latent deviation?

Answer 3

Recovery and speed of recovery. Follow it by another cover/uncover to ensure the deviation remains latent and that there’s no deterioration in recovery speed

Question 4

If VA is uneven what must you look for?

Answer 4

Microtropia

Question 5

What are the estimations of size during a cover test?

Answer 5

Fractional/Minimal = <5 degrees or 10PD
Slight or Small = 5-10 degrees or 10 - 20PD
Moderate = 10 - 20 degrees or 25 - 35PD
Marked = >20 degrees or >40PD

Question 6

What is convergence excess esophoria?

Answer 6

When esophoria is greater on near than distant fixation

Question 7

What is divergence weakness esophoria?

Answer 7

When esophoria is greater on distant fixation than near fixation

Question 8

What is non-specific esophoria?

Answer 8

When there is no significant degree of change at either near or distance

Question 9

What is convergence weakness exophoria?

Answer 9

When an exophoria is greater on near than distant fixation

Question 10

What is divergence excess exophoria?

Answer 10

When an exophoria is greater on distance than near fixation

Question 11

What is non-specific exophoria?

Answer 11

Exophoria that doesn’t vary significantly in degree at either near or distance

Question 12

What is alternating hyperphoria (or hypophoria)?

Answer 12

When either eye rotates upwards on dissociation as a result of extraocular muscle imbalance (or the reverse)

Question 13

Why should the target be held in primary position?

Answer 13

Otherwise it can cause a false impression of the deviation e.g. A & V patterns

Question 14

If the individual wears bifocals what should you do during a cover test?

Answer 14

Get them to look through the appropriate section for the distance they’re looking at