Amblyopia is an eyesight problem in which a person’s vision is reduced in one eye usually, despite the eyehealth being normal. Also known as ‘lazy eye’, amblyopia occurs when the eye fails to develop normally during the childhood years.
In order for vision to occur, light from an object must enter the front of the eye (the cornea) and then form an image on the back of the eye (the retina). The retina is made up of millions of light-sensitive nerve cells that convert the image into an electrical signal. This electrical signal is then sent via a series of nerves (called the ‘visual pathway’) to the back of the brain.
At birth the visual pathway is not completely developed, as a child grows, the quality of the visual pathway improves and the child’s vision gradually improves as a result. For the visual pathway to develop properly the image on the retina must be clear and in focus. If the image is blurred, obstructed, or not properly aligned, then the visual pathway cannot develop correctly and the resultant vision will not reach its full potential unless therapy is begun.
Possible causes of amblyopia;
- Strabismus (‘turned eye’ or ‘squint’),
- Large degree of refractive error (longsightedness or astigmatism, especially if one eye is more longsighted than the other),
- Physical obstruction the vision such as a droopy eyelid or a cataract.
Because these conditions may only affect one eye it is not uncommon for amblyopia in a child to go unnoticed. Often this condition will only be detected when the child has their eye’s examined with an optometrist.
Treatment for amblyopia is best done in the early years of life, however it is possible, albeit more difficult, to treat later.
We recommend that all children have their first complete eye examination at 3-4 years of age, then again in the year prior to school commencing.