Amblyopia or Lazy eye is a condition where a child’s eye sight does not develop as it should. The problem is usually just in one eye but can sometimes affect both eyes.
In patients with Amblyopia, their brain focuses more with the better eye and ignores the affected eye. If the eye is not activated, then those brain cells responsible for vision do not mature normally.
Amblyopia is one of the common causes of monocular vision loss or blindness and affects 2 to 3 percent children worldwide. The term lazy eye is inaccurate as there is no problem in the eye. In fact it is the brain which is at fault .Hence brain should be called lazy rather than the eye.
A child with lazy eye will not be able to focus properly with one of his/her eyes. The other eye will make up for the problem so much so that the affected eye suffers further. If this goes on for months or years then the vision in eye that sees blurred image will deteriorate. The brain won’t receive a clear signal from the affected eye and hence will start to ignore this eye.
In most of the cases the brain and the better eye makeup for the shortfall so well that a child does not have any problem with the vision. In these cases the problem gets detected during a routine examination.
- Double vision.
- Inability to perceive depth correctly.
- A squint.
- Eyes may not appear to work in sync.
What causes lazy eye?
Anything that causes a blurring of vision or the eye to squint can provoke lazy eye. Below are the examples of possible causes:
Muscular imbalance of muscles that position the eye
This leads to squinting of the eye which in turn leads to inability of the eyes to track the object together in a synchronized way.
Unequal error in refraction.
This means unequal error in the sight. For example one eye might be very shortsighted or has lot of astigmatism while the other does not have. If the difference in the power is more, then the eye with higher refractive error or the poorer sight is likely to suffer. A child with will be more short sighted or far sighted in one eye than the other eye resulting in Amblyopia developing in the eye that has relatively poorer vision
Due to deprivation of stimulus
One eye or both are prevented from seeing and hence become lazy. This is the most common cause of Amblyopia and could be due to
- Baby is born with the clouding of the lens.(Congenital cataract )
- Droopy eye lid.
- Corneal scars
- Injury to the eye
Routine eye check up.
Vision problem ideally needs to be diagnosed before six years of age. Children should have their first eye examination before they start school, or between the age of 3 to 5 years. This means that most cases of Amblopia are diagnosed and subsequently treated timely.
There are two approaches to lazy eye treatment:
- Treatment of underlying problem.
- To force the brain to use the affected eye.
- Glasses -Most children with Amblyopia will need glasses to help focus, which have to be worn at all times so that a specialist can monitor how effective they are in alleviating the problem. Most of the times, glasses can treat the Amblyopia and no more treatment is required.
- Surgery-Cataract, corneal scars and droopy lid can be surgically corrected.
- Patching– A patch is placed over the better eye so that the lazy eye is put to work. As the child keeps using the lazy eye his/her vision improves. The length of treatment depends on many factors which include the age of the child, severity of the problem and instruction of the doctor which the child has followed. The patch is usually worn for a few hours every day. It can take weeks or months for an eye patch to improve vision.
Treatment tends to be more effective in younger children. Once the child reaches 7 years of age, the likelihood of effective treatment drops substantially.
Where the eye is not properly aligned, this becomes a permanent feature if left untreated.
If the problem is not treated then the child loses his/her vision which is usually irreversible or permanent. The child will not be able to perceive depth accurately and this makes him unable to perform certain tasks efficiently.
If you have a doubt that your child has a vision problem, get him checked promptly for timely management to prevent the occurrence of Amblyopia.
Early diagnosis and treatment are the keys to the best visual outcome.