What is amblyopia

Amblyopia is where the vision in one eye is reduced compared to the other eye. It affects 4% of the population. Sometimes this is described as a 'lazy eye'.

In children it often doesn't cause any symptoms but can be detected at a school eye screening check or at a routine optician examination. It can be associated with strabismus ( a misalignment between the eyes). 

The term 'lazy eye' can also be used to describe other conditions, for example, a droopy eye lid (ptosis), strabismus ( a misalignment between the eyes) or 'squinting' or closing one eye to see or in bright sunlight. 

WHAT CAUSES AMBLYOPIA

---

• A difference in the Refractive power between each eye. If one eye has a higher refractive error than the other eye, for example, one eye is significantly more long sighted (hypermetropic) or short sighted (myopic), the brain will choose to 'ignore' the eye with the stronger refraction and so the vision won't develop properly. 
• A squint or strabismus. If there is a misalignment between the eyes (one eye is turning in or outwards) this may lead to amblyopia in the eye with the turn.
• Stimulus deprivation. If the vision in childhood is temporarily impaired by a cataract or droopy eyelid (ptosis) this leads to unequal signal from each eye going to the brain and the vision in the affected eye will be underdeveloped. This will remain even after the cause has been treated.

CAn ambLyopia be treated?

If this is detected in childhood then ambyopia can be treated. Treatment works best before the age of 7 but if a child is older has never had amblyopia treated previously it is worth being assessed to see if they would still benefit from treatment.

• Correct the refractive power. The first step is to correct any significant glasses prescription between the two eyes. Glasses should be worn full time. Sometimes a weaker prescription will be given to start with and increased to your child's full glasses prescription as needed. After a period of wearing the glasses for a few weeks the vision is reassessed to see if further treatment is needed to strengthen the weak eye.
• Occlusion or Patching therapy. This is one option to help improve the weaker eye. The good eye is covered for a period of time eg 2 hours a day to make the brain use the weaker eye. It is good to do focused tasks during this time, for example, reading. We will advise how many hours are needed based on how weak the vision is.
• Atropine eye drops. A drop is put into the 'good eye' every Saturday and Sunday. This dilates the pupil and blurs the vision in the good eye making the brain use the weaker eye.  We will advise with treatment option is most suitable for your child and the risks and benefits.
• Strabismus surgery. There is no surgery that improved the visual acuity but once the vision has been maximised with the amblyopia treatment then surgery for any eye misalignment can be considered.

Whilst undergoing amblyopia treatment it is important that your child is regularly assessed and monitored so that we can advise on progress and the next steps.