Active Vision Therapy II

Amblyopia (Lazy Eye)

Amblyopia (lazy eye), means that the eye has not developed normally and always has blurred vision, even with the best spectacle glasses or contact lenses your eye surgeon or the optometrist can prescribe.

Amblyopia is caused when the brain favors one eye and refuses to use the other. Simply stated, amblyopia is a dysfunction of the brain which blocks vision from one eye because it can’t use the two eyes together. Because the eye is “turned off, ” clear vision does not develop in the lazy eye. Amblyopia affects 2 to 3 percent of the population.

Amblyopia (lazy eye) is a unilateral or bilateral reduction of corrected visual acuity without any visible defect in the eye commensurate with this loss. It is a common functional defect in children that can be very challenging to treat, caused by vision deprivation, abnormal binocular interaction, or both and for which no organic cause can be detected by physical methods. In many cases, it is reversible by therapeutic measures.

How A Lazy Eye Develops

The brains of children who have a lazy eye, however, did not learn to use their two eyes together. At an early age, these children only used one eye, and their brain “turned off” or blocked the in-coming picture from the other eye. Turning off an eye is called suppression. Therefore, a child with a lazy eye not only sees out of just one eye, but as a result he also has poor depth perception and limited side vision in the eye he is suppressing.

Because the brain turned off the lazy eye very early in life, it did not develop normal sharpness of vision, called acuity. Therefore, a lazy eye has very poor eyesight; vision out of the weak eye is blurred. This “use it or lose it” syndrome means that the child has lost the ability to see clearly out of the lazy eye, even with the best pair of glasses or contact lenses, the eye surgeon can prescribe. How poor the vision is in the weak eye depends in part upon how early in the child’s visual development the brain turned the eye off.

Strabismus (Squint or Crossed Eye) is the Most Common Cause of Lazy Eye

Amblyopia is caused by various conditions that prevent the brain from using both eyes together. In some cases, the tendency for a lazy eye may be inherited. One type of lazy eye, called refractive amblyopia, is caused when each eye needs a different prescription, making it difficult for the eyes to focus together. In this situation, the best prescription for glasses or contact lenses is used to help equalize the vision in each eye.

One of the most common causes of a lazy eye, however, is strabismus ( squint ). Strabismus, commonly referred to as a crossed or wandering eye, is a condition in which the brain is unable to properly align the eyes. As a result, one eye may point in or out, up or down. When the eyes are not pointing at the same place, two different pictures are being sent to the brain. Because the brain can’t combine two obviously different pictures into a single image, the result is double vision. The brain is then forced to turn off the picture coming in from the misaligned eye to avoid seeing double. The child only uses his straight eye to see, and vision in the turned eye does not have a chance to develop.

Treatment of Lazy Eyes

To correct amblyopia, the weak eye must first be forced to work in order to allow the opportunity for clear vision to develop. This is usually done by patching the strong eye for specific periods of time, forcing the weak eye to “turn on” and practice working. Secondly, glasses are prescribed to provide the weak eye with the best support possible. Finally, squint—the underlying cause of the lazy eye in most of the cases must also be corrected.

In addition to glasses, there are three different approaches to the treatment of a lazy eye:

1. patching alone,
2. patching combined with surgery, and
3. patching combined with active vision therapy.

It is imperative that parents of a child with a lazy eye fully understand their treatment options so that they can make the best choice for their child. It is only with their cooperation and active participation that we can get the best results. It is imperative to assess the motivation of the child’s parents. Their understanding and willingness to co-operate in this complicated care of the child is essential if there is to be any hope for useful vision.

Patching Only

When the treatment procedure involves patching only, the child’s strong eye is covered for eight to twelve hours a day over a long period of time, usually weeks or even months. By forcing the weak eye to work full time, its vision improves. However, there are serious drawbacks to this option. First, because the good eye is covered for most of the day, the child cannot see well and is often frustrated and uncooperative. It becomes difficult for the parents to keep the patch on the child all day long, week after week. Often the patch has to be taped over the child’s eye to prevent him from removing it. Over a period of time, the skin around the eye can become irritated and raw. Also, there is danger of loss of vision in the good eye when it is covered most of the time for weeks on end. In the face of these hardships, patching often fails because the child and parents give up.

Unfortunately, the gains from patching are not always permanent. Even if the family successfully makes it through the original patching ordeal, it is not uncommon for the child to have to continue with periodic patching in order to maintain the improvement in vision. This is because strabismus (squint), or the other underlying cause of the lazy eye, was not treated. Because a lazy eye is a brain-based problem, the brain must be taught to align and use the two eyes together. Without intervention to train the brain how to correctly use both eyes simultaneously, a child’s visual system will still suppress the weak eye. As a result, much of the lazy eye’s gains from patching will be lost over time. Once patching is stopped, the vision in the lazy eye degenerates if nothing has been done to teach the child’s brain to use both eyes together.

Patching With Surgery in Cases of Squint

In addition to a full time patching regimen, eye surgeons sometime recommend surgery to “correct” the strabismus, or crossed eye. Unfortunately, eye surgery does nothing to restore normal two-eyed vision, which is a learned process of the brain. Surgery simply makes the eyes appear straight by cutting muscles and repositioning the eyes in the head, a cosmetic “fix” but not a visual cure. Surgery cannot correct the improper habits the brain learned which caused the misalignment problem to begin with, nor can surgery train the brain how to use both eyes together. Most children who have undergone surgery for a crossed eye still suppress one eye full time. In order for the problem to be truly corrected, the brain must “unlearn” suppression and be trained to use both eyes together.

On an average, less than 20% of children who undergo eye surgery eventually achieve normal two-eyed vision. The few who do are nearly always very young children under the age of six years whose visual systems were still developing and fluid enough to fall into binocularity on their own.

Misconceptions about the “Critical Stage” for Treatment of Amblyopia

It is for this reason that some parents are told that a lazy eye can only be corrected when the child is very young, usually age six or under, the time when a child’s visual system is still naturally “moldable.” Some doctors feel that if treatment is not undertaken during this “critical stage” of development, the amblyopia becomes fixed and untreatable. Parents of older children with lazy eyes are often told that it is too late to treat the problem.

While these doctors are well intentioned, they are wrong. Eye surgeons who believe that a lazy eye cannot be treated after the age of six years simply lack the background and necessary training to correct a lazy eye in older children. Because they are not schooled in the functional remediation of binocular vision problems, they do not have the capability to treat older children. It is true that correcting amblyopia in a younger child makes the treatment easier, but older children and even adult patients can be cured of a lazy eye through active vision therapy. We have treated more than 5000 patients over the past 8 years and many of our patients are above the age of 20 years.

ACTIVE VISION THERAPY

Active Vision therapy is much like physical exercises for the eyes. Active Vision therapy is prescribed by eye surgeons who specialize in children’s vision and are experts in the diagnosis and treatment of children’s vision disorders, including amblyopia and strabismus. Active Vision Therapy is highly successful in improving the function and performance of a lazy eye. The therapy corrects not only the poor vision in the lazy eye, but it also corrects the underlying problem of the brain’s inability to align and use both eyes together. During therapy, the patient’s brain is trained to stop suppressing the lazy eye, the visual pathways from the brain to the eyes are improved so the patient can keep both eyes aligned, and finally, the brain is taught to fuse the images coming in from both eyes for normal binocular (“two-eyed”) vision. Our research and experience have shown that active vision therapy restored the visual system to normal in 92% of cases. Even in the remaining 8% of cases, those most severe instances of lazy eye complicated by additional circumstances, therapy could improve the child’s sight to more functional levels. And this can be done at any age, even into adulthood. An older child or a patient with difficult complications will need therapy for a longer period of time, but success at rehabilitating a lazy eye is possible for all children regardless of their age. Come and see the results at our center.

When amblyopia treatment is limited to only patching or surgery, no measures are taken to rehabilitate the dysfunctional vision system. Consequently, any treatment that does not address the root cause of the problem is entirely dependent upon the fixed time frame when vision normally develops. Active Vision Therapy, on the other hand, aggressively stimulates and guides visual development, actually reprogramming the brain to perform visual functions not previously developed on its own. When active vision therapy actively develops the patient’s visual acuity and improves binocular function, all children can experience excellent clinical results.

Like other interventions, active vision therapy usually involves patching the strong eye to force the weak eye to work, but for much shorter periods of time, sometimes not at all, if the child resists it. Rather than full-time patching for up to twelve hours a day, a patient in active vision therapy will usually be asked to patch for two hours. Much less patching time is necessary when the child’s visual system is also being trained on how to use the weak eye properly. By the end of therapy, the child’s patching time will be eliminated altogether. The gains achieved in active vision therapy are permanent. This is because once the child’s brain learns binocularity, or how to fuse the images from both the left and right eye together, the child’s visual system has been fully restored to normal. The fusion of the two eyes’ images is the glue, which permanently holds the vision system in place because it’s easier to see correctly than to have each eye see separately. Binocular fusion keeps the eyes from drifting out of alignment; and because there is no longer a need for the lazy eye to suppress, its improved acuity, or sharpness of vision, is not lost over time.

Some of the Conditions Which We Have Treated

1. Functional causes:

• Strabismus (Squint or cross eye)
• Uncorrected anisometropic myopia.(short-sightedness)
• Uncorrected anisometropic hypermetropia(long-sightedness)
• Uncorrected anisometropic astigmatism
• Combined anisostrabismus

2. Refractive causes

• Uncorrected isometropic myopia
• Uncorrected isometropic hypermetropia
• Uncorrected astigmatism

3. Visual deprivation causes

Ptosis

Following surgery for Cataracts in children

• Binocular Congenital Cataract
• Unilateral Congenital Cataract
• Traumatic Cataract

Corneal opacities

4. Structural/Pathological causes

• Microcornea
• Albinism
• Aniridia
• Marfan’s Syndrome
• Coloboma
• Keratoconus
• Macular or paramacular pathology
  • Macular burn
  • Heredomacular Degeneration
  • Retinitis Pigmentosa
• Nystagmus

5. Miscellaneous causes

Following surgery for IOFB, endophthalmitis

• Following PRK
• Following Retinal detachment surgery
• Following PP Vitrectomy

Some of the Conditions For Which Orthoptic Training is Given at Our Center

• Convergence Insufficiency
• Fusional problems
• Accommodative problems
• Accommodative squint
• Accommodative Asthenopia
• Tracking and teaming problems
• Learning disorders
• Re-training stereopsis
• Dyslexias
• Heterophorias
• Antisuppresion exercises
• Correction of abnormal retinal correspondence

Apart from the above-mentioned conditions, Active Vision Therapy and Orthoptic Training have a strong role in improving visual acuity and the quality of vision in many other conditions.

A lazy eye is not always easily recognized. A child may not even be aware that one of his eyes is not working with the other. If the eye turn is so slight that the child does not have an obvious misalignment, parents will rarely be able to tell something is wrong just by looking. It is extremely important for children to develop equal vision in both eyes in order for them to function normally. Good sharpness of sight and two-eyed binocular vision is vital for children to succeed in school, sports, or any other activity that requires clear vision, good hand-eye coordination, and strong depth perception. When children with untreated amblyopia grow to be adults, their choice of career may be limited and, if they are unlucky enough to lose vision in their one good eye, they could be visually impaired or legally blind for life. For these reasons, it is extremely important for parents to have their child’s eyes examined by an eye surgeon as early as possible so vision problems can be found and treated. Vision can be tested in infants and very young children, and it is recommended that a child be examined at least by the age of three.

However, if you are a parent of a child with a lazy eye who was diagnosed after age six, please do not be misled. There is help. Active Vision Therapy demands much perseverance from the patients and the therapists. With the increasing visual demands of a technology-oriented society, amblyopia is becoming a socioeconomic problem. During the first 45 years of life, amblyopia is responsible for the loss of vision in more people than all ocular diseases and trauma put together.

Dr. Arun Verma,
c/o Dr. Daljit Singh Eye Hospital,
outside Sheranwala Gate, Amritsar
Residence: 20 Sandhya Enclave, Majitha Road,

Amritsar, India. Ph No. 0183-572567, 421237

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