BVP - Clinical Aspects of Amblyopia - Week 3

Question 1

Is acuity the only defect in amblyopia and describe acuity testing in this context (2).

Answer 1

Acuity defect is not the only defect in amblyopia, but acuity testing is the cornerstone of diagnosis
-its easy to measure
-reliable test

Question 2

What should be considered when doing an acuity test for amblyopia?

Answer 2

Contour interaction

Question 3

What acuity test is the most sensitive to amblyopia? Describe the capacity of each acuity test usable for this purpose (2).

Answer 3

LogMAR is the most sensitive to amblyopia
Snellen is not as sensitive and acuity is overestimated by 1-3 lines

Question 4

What does acuity does VEP show at 6 months of age?

Answer 4

6/6 by 6 months of age

Question 5

Is it possible to test a child under 2.5 years with a chart? What about 2.5 - 3.5?

Answer 5

Under 2.5 - No
2.5 - 3.5 - picture charts

Question 6

At what age can a letter chart be used?

Answer 6

5.5 - 6 years old

Question 7

What is better in amblyopes, single letter acuity or line acuity? Keeping this in mind, what will single letter acuity often tell you and what is advised (2)?

Answer 7

Single letter acuity is much better
-will often tell you there is no amblyopia when there is
-beware using a snellen chart

Question 8

What can be used for acuity testing in 6 month - 3 year old children? What would you expect to see in strabismus? Are teller acuity cards generally used?

Answer 8

Fix and follow
Alternation in strabismus
Teller acuity cards generally not used

Question 9

When should sweep VEP be done (2)?

Answer 9

If concerned a child might be blind or have low vision

Question 10

Do kays pictures have high testability?

Answer 10

Yes

Question 11

Which has less developmental noise, kays pictures or lea chart?

Answer 11

Kays pictures

Question 12

What preliterate form of acuity testing ha the highest sensitivity to amblyopia?

Answer 12

Lea chart

Question 13

List four amblyogenic factors. Does one need to be found?

Answer 13

You need an amblyogenic factor
-strabismus
-anisometropia
-high bilateral refractive error
-media opacity/ptosis

Question 14

What should you do if you suspect amblyopia in the absence of an amblyogenic factor? What should also be kept in mind concerning amblyopia?

Answer 14

Refer to an ophthalmologist
Amblyopia should respond to treatment in children at least to 6/12

Question 15

List five prognostic indicators of amblyopia.

Answer 15

The cause of amblyopia
The length of time the amblyogenic factor was present
The age of the child at the time of treatment
Eccentric fixation
High refractive error or large anisometropia

Question 16

What is the primary purpose of amblyopia treatment?

Answer 16

Achieve normal VA and fixation in each eye separately

Question 17

What is the secondary purpose of amblyopia treatment?

Answer 17

Achieve normal fusion at all levels and correspondence with both eyes open

Question 18

What spectacles will amblyopia respond best to and what should you remember to do?

Answer 18

Responds best to full plus worn full time
-remember to recheck the prescription and the hyperopia has not increased

Question 19

Will amblyopia respond to visual input without occlusion?

Answer 19

Partially

Question 20

What is essential for amblyopia before commencing patching?

Answer 20

Optimal refractive correction

Question 21

Describe how amblyopia is a diagnosis by exclusion.

Answer 21

Records must show that the macula and optic nerve is intact