What is Amblyopia/ “Lazy eye”?
- Decreased vision in one or both eyes due to insufficient use in infancy or childhood
- Visual acuity in either eye worse is 6/12 or there is more than 2-line difference in visual acuity between the 2 eyes
How does amblyopia/ “Lazy eye” develop?
- During the critical period of early childhood from birth to six years of age, anything that interferes with clear vision in either eye can result in amblyopia.
- Vision loss occurs because nerve pathways between the brain and the eye aren’t properly stimulated
- As a result, the brain favours one eye, usually due to poor vision in the other eye
- The brain doesn’t learn to see clearly with the amblyopic eye, and even If the visual problem of the eye is corrected later in life, the image interpreted by the brain may still be unclear.
Causes of amblyopia
- Strabismus or squint
- Vision deprivation
- Ptosis/droopy eyelid
- Refractive error ((nearsightedness, farsightedness or astigmatism)
- Large refractive error or unequal amount of refractive error between both eyes
The end result of all forms of amblyopia is reduced vision in the affected eye(s).
What symptoms should I be looking for in my child?
- The only way to detect a lazy eye is to have sight tests regularly throughout childhood
- Children should be checked at birth, at six months and annually thereafter.
- A lazy eye can go undetected if only one eye is affected.
Is the risk of vision loss high in amblyopia?
- With early diagnosis and treatment, the sight in the lazy eye can be restored
- The earlier the treatment, the better the chance to correct the vision loss
- Amblyopia is most successfully treated up to 7 years of age, but there may be SOME improvement with amblyopia therapy up to 14 years of age
What treatment options are available?
- If necessary, children with refractive errors (nearsightedness, farsightedness or astigmatism) can wear glasses
- Children with cataracts, squints or other conditions that can reduce vision are usually treated promptly
- Patching of the better seeing eye allows the weak eye to get stronger. This could be a disposable adhesive patch or a patch held in place with elastic. The more complete the blockage of light from the eye, the more effective the treatment.
- Successful patching requires persistence and constant encouragement from family members, teachers, neighbours etc.
- Explain clearly to your child the reason behind treatment as well as the benefits it has to their vision.
- Children may refuse initially, but by encouraging or providing a reward to the child for keeping the patch on for the prescribed time period, they will eventually learn not to remove the patch
- “Penalize” or blur the stronger (good) eye with atropine eye drops temporally may work for children who persistently resist patching