Treating Kids with Amblyopia
An eye disorder that start in young children, amblyopia occurs when one eye is relatively weaker than the other eye, though both eyes appear identically normal from a morphological point. The weakness means that one eye has either a poor focus or transmission to the optic nerve so that on its own, could not perceive as well as the other normal eye. It can mean partial or complete visual loss in one eye.
The term "amblyopia" is rooted on the Greek portmanteau made up of "amblys" for blunt, dull, faint, or dim and “ops" for eye, which make the word literally mean dim vision. It is often used interchangeably with “lazy eye” to denote the eye with a visual deficiency. The condition is the most common trigger for monocular blindness where one eye suffers complete or partial visual loss. It afflicts an estimated 1% to 5% of the population and 2% to 3% of children in the US.
The triggers for the condition also determine the type of amblyopic condition.
- Strabismic amblyopia is caused by strabismus or misaligned eyes such as estropia (crossed inward), extropia (crossed outward).
- Anisometropic or refractive amblyopia is caused by a major refractive difference exist between the two eyes ranging from nearsightedness, farsightedness or astigmatism in one eye.
- Form deprivation amblyopia is triggered by congenital cataracts or corneal scarring that may be caused by forceps injuries at birth, including any corneal disease that prevents light from entering the eye or an injury to the cornea as a child
- Occlusion amblyopia is caused by ptosis or eyelid drooping or some disorder that cause the upper eyelid to occlude a child’s vision.
Amblyopia is a developmental problem in the brain and less as an organic neurological dysfunction in the eyeball. Direct brain examination of amblyopic patients confirms that the part of the brain receiving or processing the images from the weak eye fails to develop its intended visual function. The associated vision brain cells are not properly stimulated to mature normally. In effect, the brain favors one eye over another
Dealing with Amblyopia While Young
Treating strabismic amblyopia or anisometropic amblyopia involves correcting the deficit by forcing the child to use the weak eye. Covering or patching the stronger eye, using glasses to blur the good eye or instilling topical atropine in the good eye has been known to force the weak eye to get stronger with regular application. The child need not wear those corrective glasses and eye patch all the time and treatment can last for weeks or months. Severe amblyopia cases may take years. But this treatment should be monitored at frequent intervals to ensure that over-penalizing the good eye does not happen. Otherwise, the child faces the risk of reverse amblyopia in the good eye.
Amblyopia involving cataracts require immediate medical intervention as soon as possible to clear up the corneal opacity and get reinforced thereafter with patching the good eye to stimulate the weak eye.
In either case, treatment is best done to the amblyopic child before age 6 and before the child's visual prowess reaches full development, typically around age 9 or 10. The earlier the treatment is initiated, the greater chances of attaining 20/20 vision and lesser psychological distress. Later treatment will take longer with lower chances of success. An amblyopic child who does not get treated may have a poor vision for life. After treatment, be sure to schedule regular medical eye checks as amblyopia can recur even after successful correction.
Treating Amblyopic in Adults
While the best treatment results can be achieved in children before they reach age 5, recent studies show that all is not lost to amblyopic kids older than 10 as well as adults. Amblyopic kids between 7 and 12 who undergo vision therapy wearing eye patches have shown two-line improvements on an 11-line Snellen chart over similar amblyopic kids who have not received treatment. Adolescents from 12 to 17 have also exhibited improved though in a smaller degree.
Virtual reality games using 3D goggles that send different visual signals to each eye for the player’s brain to combine to navigate through the game promises to improve monocularity in the weak eye and binocularity as well.
A recent research study suggested that transcranial magnetic stimulation done repetitively may provide temporary improvement in spatial perception and contrast sensitivity in the weak eye of amblyopic adults.