Amblyopia, medically termed as the Lazy Eye Syndrome is a visual development disorder that generally affects children. If left untreated, the condition can lead to permanent blindness
Amblyopia or Lazy Eye Syndrome is a condition in which one or both eyes have subnormal vision, in spite of the absence of any structural problem in the eye. The condition is often known to start early during childhood and in most cases only one eye is affected. The progress of this visual development disorder can be curbed if the treatment starts during the early stages itself.
As of now, amblyopia is one of the leading causes of childhood visual impairment globally. It is estimated that this condition is prevalent in about 2-12 per cent of the children in various parts of India.
Signs and symptoms
Since the Lazy Eye Syndrome generally affects only one of the eyes while the other functions normally, children are unable to detect the irregularity in their vision and the condition goes undiagnosed for quite some time. However, there are certain prominent symptoms that highlight the presence of this condition to parents.
For instance, if your child has a squint in the eyes or some other apparent eye misalignment, it is best advised to consult an ophthalmologist as soon as possible to have it examined in depth. Another symptom is when the child finds it difficult to see clearly if one of the eyes is patched. In fact, this is like a simple screening test that most parents can easily conduct in their homes as well to identify the presence amblyopia in its initial stages. If either of the eyes is amblyopic, vision from it is likely to be blurred.
However, it is still important to have your child’s eyes examined at regular intervals by an expert ophthalmologist in order to identify problems like amblyopia as early as possible.
What causes amblyopia?
One of the major causes of amblyopia is squint or crossed eyes in children where the vision is not proper due to misalignment in the eyes. When a child develops this condition, the brain chooses to ignore the visual input from the misaligned eye and this makes it ‘lazy’ or amblyopic.
Another common cause of amblyopia is anisometropia or a condition that arises from a relatively large difference in refractive error between the two eyes. Even ammetropia or large uncorrected refractive error in both eyes can lead to the development of amblyopia.
Stimulus deprivation or conditions that do not let the light pass into the eye such as cataract, ptosis, corneal scars can also cause amblyopia in children.
In some cases, children can also develop amblyopia due to unequal refractive errors in both eyes inspite of perfect alignment. However, misalignment in the eyes continues to be one of the most common causes that lead to amblyopia. If the child develops any of these conditions, it will lead to poor image formation or simply a difference in the images perceived by the two eyes. Hence, the normal process of achieving visual maturation remains incomplete once the child develops amblyopia.
Basically, the treatment for amblyopia is summed up in 5P’s which are: Principal cause treatment (e.g. pediatric cataract / keratoplasty/ strabismus surgery), Patching, Penalisation, Persistence of the parents and the physicians to help the child adapt.
Depending on the seriousness of the case, the doctor may prescribe use of prescription spectacles, surgery for pediatric cataract, ptosis, squint and other conditions along with therapy that will teach children to make the most of their existing visual capabilities in spite of being affected by amblyopia or ‘lazy eye’.
These specific treatments stimulate the vision in the weaker eye and help the part of the brain that manages vision to develop more completely. This is also combined with about one hour/ day of intensive treatment session with visual stimuli which is called ‘near vision exercises’.
Early diagnosis and screening and appropriate management play a very vital role in treatment of amblyopia. This is because the success rate of all treatment and therapy dramatically reduces with increasing age.
Recent years have also shown further research in the management of amblyopia and novel therapies such as acupuncture, binocular stimulation, magnetic stimulation and computer vision exercises especially I-pad based exercises can be effective in curing the condition. Of these, I-pad based dichotic exercises have shown significant success in patients. At present, these can be considered useful as a supporting treatment to standard patching/penalisation therapy, however, further research is still ongoing in order to establish their effectiveness to restore visual acuity.