Amblyopia = Lazy Eye
It is perfectly natural as a parent to feel anxious and a little upset by the fact that your child has lazy eye (amblyopia), particularly if you were unaware of the problem before your child’s eye examination. You may have noticed a turned eye, favouring one eye, bumping into objects on one side, head tilt or that they don’t perform certain visual and eye-hand tasks as well as expected.
Amblyopia, or ‘lazy eye’, affects up to 4% of the population and is a condition where the message, sent from the affected eye or eyes to the brain, is of low quality, making the sight of that eye poor. A person with amblyopia will have poor vision that doesn’t fully correct simply with spectacles.
Simply stated amblyopia is not “medical.” There is no disease. There is no drug or surgery to cure it. This is a neurological condition. The part of the brain that processes detailed information from that eye (or eyes) is under-developed due to lack of stimulation. The child simply has not learned to see clearly (vision) with the eye. The only treatment is to stimulate vision development.
Common causes of this are a turned eye or a large difference in the extent of shortsightedness, long-sightedness or astigmatism (refractive error) between the person’s eyes. Rare causes of Amblyopia can include disease or injury to the nerve connecting the eye to the brain, some psychiatric conditions and excessive use of tobacco, alcohol or other drugs.
Visual development is incomplete at birth. The basic components of the visual system are present, but a child’s visual system continues to develop after birth in response to the visual environment. This development progresses rapidly in the first few years of life and can be subject to stressors which impede normal progress.
In a person with Amblyopia, the message received by the brain from each eye is different. This occurs when there is lack of clear focus, or because the eyes are pointing in different directions. The brain compensates for this difference by ignoring the message from the worse eye. If a visual system is not corrected within the first 7 to 8 years, the child may never develop the ability to process the image from the worse eye. A thorough eye examination is the only sure way of determining whether your child has Amblyopia. If you think that there may be something wrong with your child’s vision, discuss it with us.
Treatment depends on the cause. Most commonly glasses, prisms, contact lenses and vision therapy programs are used to train the poor eye to function normally. For 300 years the better eye has been covered with a patch to encourage use of the lazy eye, however recent research indicates other mechanisms such as a combination of syntonics, binasal occlusion, refractive engineering, vision therapy and monocular fixation in a binocular field are often more effective in improving acuity and encouraging effective binocular vision. Some special or rare types of Amblyopia are treated simply by improving the person’s general health. The earlier Amblyopia is detected, the easier it is to treat.
It is important to be secure in the diagnosis and be committed to the program when you do start vision therapy. A second opinion to rule out pathological causes is never discouraged.
- Hyperopia (long-sightedness)
- Myopia (shortsightedness)
- Vision and school achievement
- Parents’ guide to children’s vision
Dr Ieuan H. Rees. (Optometrist)
Buck & Todd Optometrist
Located in City Plaza, 45 Wood St. Mackay.