Amblyopia

Amblyopia, also known as lazy eye, is an eye disorder characterized by an impaired(decreased) vision in an eye that otherwise appears normal, or out of proportion to associated structural abnormalities of the eye. It has been estimated to affect 1-5% of the population.

In amblyopia, visual stimulation either fails to transmit or is poorly transmitted through the optic nerve to the brain for a continuous period of time. It can also occur when the brain "turns off" the visual processing of one eye to prevent double-vision, for example in strabismus (squint/crossed-eyes). It often occurs during early childhood, resulting in poor or blurry vision. Amblyopia normally affects only one eye in most patients. However, it is possible, though rare, to be amblyopic in both eyes, if both fail to receive clear visual images.

Detecting the condition in early childhood increases the chance of successful treatment, especially if detected before the age of five. The earlier it is detected, and the underlying cause corrected with spectacles or surgery, the more successful the treatment in equalizing vision between the two eyes.

Mechanism of Amblyopia

Amblyopia is a developmental problem in the brain. The part of the brain receiving images from the affected eye is not stimulated properly and does not develop to its full visual potential. The critical period of visual development in humans is up to 2 years of age.

Facts of Amblyopia

If not got detected in its early stage, Amblyopia can cause marked decrease of vision along with decreased depth perception. 

In recent research on this condition, it is been found that it is easier to correct this condition in children than in adults. 

Without doing a complete eye check this condition will never get detected. Infants and pre-school going children should go for complete eye checkup to rule out this condition. 

Symptoms of Amblyopia

Many people with amblyopia, especially those who only have a mild form, are not even aware they have the condition until tested at older ages, since the vision in their stronger eye is normal. However, people who have severe amblyopia may experience related visual disorders, most notably poor depth perception. Amblyopes may suffer from poor spatial acuity, low sensitivity to contrast and some "higher-level" deficits to vision such as reduced sensitivity to motion. These deficits are usually specific to the amblyopic eye. Amblyopes also suffer from problems of  binocular vision such as limited stereoscopic depth perception and usually have difficulty seeing the three-dimensional images in hidden stereoscopic displays such as autostereograms. However, perception of depth from monocular cues such as size, perspective, and motion parallax remains normal.

Types of Amblyopia

Amblyopia has three main causes:

1. Strabismic: by squint/strabismus (misaligned eyes)
2. Refractive: by anisometropia (high degrees of myopia/nearsightedness ,hyperopia/farsightedness, or astigmatism in one or both eyes)
3. Deprivational: by deprivation of vision early in life by vision-obstructing disorders such as congenital cataract 

Treatment of Amblyopia

Treatment of strabismic or anisometropic amblyopia consists of correcting the optical deficit (wearing the necessary spectacle prescription) and often forcing use of the amblyopic eye, either by patching the good eye, or by instilling topical atropine in the good eye.

Eye patching is usually applied on a part-time schedule that is about 4-6 hours a day. Treatment is continued as long as vision improves. It is not worthwhile continuing to patch for more than 6 months if there is no improvement.

Deprivation amblyopia is treated by removing the opacity as soon as possible followed by patching or penalizing the good eye to encourage use of the amblyopic eye. The earlier treatment is initiated, the easier and faster the treatment is and the less psychologically damaging. There is also a greater chance of achieving 20/20 vision if treatment is initiated as early as possible.

Early diagnosis increases the chance for a complete recovery. This is one reason why we recommend that children have a comprehensive eye examination by the age of 6 months and again at age 3. Lazy eye will not go away on its own. If not diagnosed until the pre-teen, teen or adult years, treatment takes longer and is often less effective.

Book an Appointment today for complete eye checkup at Diveeksha Eye Clinic an ISO 9001:2008 certified eye clinic located in Sector- 20, Noida.