AMBLYOPIA

Question 1

 Unilateral or less commonly, bilateral reduction of best corrected visual acuity that cannot be attributed directly to the effect of any structural abnormality of the eye or the posterior visual pathway. Defect of central vision.

Answer 1

AMBLYOPIA

Question 2

Most common form of amblyopia. thought to result from competitive or inhibitory interaction between neurons carrying the nonfusible inputs from the two eyes.

Answer 2

Strabismic Amblyopia

Question 3

It develops when unequal refractive error in the two eyes causes the image on the one retina to be chronically defocused.

Answer 3

Anisometropic Amblyopia

Question 4

Uncorrected bilateral astigmatism in early childhood may result in loss of resolving ability limited to chronically blurred meridians.

Answer 4

Meridional amblyopia:

Question 5

Isometropic amblyopia result from large, approximately equal, uncorrected refractive error in both eyes of a young child.

Answer 5

Amblyopia Due to bilateral high refractive error (isometropia)

Question 6

• It is usually caused by congenital or early acquired media opacity.
• This form of amblyopia is the least common but most damaging and difficult to treat.

Answer 6

Stimulus Deprivation Amblyopia

Question 7

allow the examiner to test the crowding phenomenon with isolated optotype. Bar surrounding the optotype mimic the full optotype to the amblyopic child

Answer 7

Crowding bar, or contour interaction bars

Question 8

• a test for estimating the relative level of vision in the two eyes for children with strabismus who are under the age of about 3.

Answer 8

Binocular fixation pattern

Question 9

is typical for amblyopia but not uniformly demonstrable

Answer 9

crowding phenomenon

Question 10

Treatment of amblyopia

Answer 10

• Eliminating (if possible) any obstacle to vision such as a cataract
• Correcting refractive error
• Forcing use of the poorer eye by limiting use of the better eye.

Question 11

 In general, optical prescription for amblyopic eyes should correct the full refractive error as determined with cycloplegia.

Answer 11

Refractive correction

Question 12

• Defined as occlusion for all or all but one waking hour.

* It is the most powerful means of treating of amblyopia by enforced use of the defective eye.

Answer 12

Full time occlusion of the sound eye

Question 13

• Defined as occlusion for 1-6 hours per day.

* The children undergoing part time occlusion should be kept as visually active as possible when the patch is in place.

Answer 13

Part-time occlusion

Question 14

• A cycloplegic agent (usually atropine 1% or homatropine 5% ) to once daily to the better eye
• This form of treatment has recently been demonstrated to be as effective as patching for mild to moderate amblyopia.

Answer 14

Penalization

Question 15

The time required for completion of treatment depends on

Answer 15

1. Degree of amblyopia
2. Choice of therapeutic approach
3. Compliance with the prescribed regimen
4. age of the patient

Question 16

When amblyopia treatment is discontinued after fully or partially successful completion, approximately half of patients show some deree of recurrence.

Answer 16

Recurrence

Question 17

Maintenance therapy

Answer 17

• Patching for 1-3 hours per day
• Optical penalization with spectacles
• Pharmacologic penalization with atropine 1 or 2 day per week.
• This may require periodic monitoring until age 8-10.

Question 18

Primary therapy should generally be terminated if there is a lack of demonstrable progress over __ with good compliance

Answer 18

3-6 months

Question 19

__ should be carefully rechecked and the macula and optic nerve critically inspected for subtle evidence of hypoplasia or other malformation that might have been previously overlooked.

Answer 19

Refraction

Question 20

______ can be used as an alternative to full-time patching if skin irritation or poor adhesion proves to be a significant problem

Answer 20

Spectacle-mounted occluder or special opaque contact lenses