AMBYLOPIA MANAGEMENT IN CHILDREN

AMBYLOPIA MANAGEMENT IN CHILDREN

Amblyopia is a reduced corrected visual acuity without evidence of organic eye disease. It is caused by abnormal visual experience during a sensitive period of visual development in early childhood, most commonly from squint or from visual deprivation caused by unequal refractive errors. It affects upto 3.5% of children and is the most common cause of uniocular visual impairment in children and adults. Occlusion therapy with patching of the sound eye has been the mainstay of amblyopia treatment. However, opinion vary on the numbers of hours of daily patching that should be prescribed for moderate amblyopia , ranging from as little as 1or 2 hours to 24hours per day. No prior study has provided conclusive data on the optimal number of patching hours. To address this clinical issue, we conducted a randomised clinical trial to compare 2 hours vs 6 hours of daily patching for moderate amblyopia in children younger than 7 years who were able to complete visual acuity testing.

CAUSES OF AMBLYOPIA

Normal vision develops during the first few years of life. At birth , infants have very poor vision. As infants grows and use their eyes ,the vision improves as the vision centre in the brain develop. If the children are not able to use their eyes , the vision centre in the brain do not develop properly and the vision is decreased. Amblyopia may occur despite normal appearance of the eye structure.

The most common cause is:

Refractive error: It can happen in one or both eye and if it not corrected early in childhood resulting in poor development of the visual function in the affected eye, this is called refractive amblyopia.

Strabismus Amblyopia: It is another cause of amblyopia in children due to the deviation of eyes.

Deprivation amblyopia : Rarely there is a structural Anamoly that impairs vision like a droopy eyelids or an opacity in the eye, such as a cataract or corneal scar. This is called deprivation amblyopia.

SYMPTOMS

Signs and symptoms of lazy eye include:

· An eye the wanders inward or outward

· Eyes that appear to not work together

· Poor depth perception

· Squinting or deviation of eye.

· Head tilting

· Abnormal result of vision screening

DIAGNOSIS

A doctor will conduct an eye exam , checking for health, a wandering eye, a difference in vision between the eyes or poor vision in both eyes. Eyedrops are generally used to dilate the eyes. The eyedrops cause blurred vision that lasts for several hours or a day.

· Preverbal children: A lighted magnifying device can be used to detect cataracts. Other test can assess an infants or toddlers ability to fix his or her gaze and to follow a moving objects.

Children age 3 and older: Tests using pictures or letters can be assess the child vision. Each eye is covered in turn to test the other eye.

COMPLICATION:

Blindness: If untreated, the patient may eventually lose vision in the affected eye. This vision loss is usually permanent.

Eye turn: Strabismus , where the eyes are not properly aligned, can become permanent.

Central vision: If amblyopia is not treated during childhood , the patients central vision may develop correctly. The problem may affect their ability to do certain tasks.

RISK FACTOR

A child might be more likely to have lazy eye if they have:

· Were born earlier(premature baby)

· Were smaller than average at birth

· Have a family history of amblyopia or other eye condition

TREATMENT

It’s important to start treatment for amblyopia as soon as possible. Depending on the cause, it might involve:

Correcting any underlying vision problems such as near sightedness, far sightedness or astigmatism. Most kids with amblyopia also need glasses to help their eyes focus.

Surgery, if a cataract is blocking light from their eye or if strabismus keeps their eyes from moving together the way they should

Wearing a patch over the strong eye to force their brain to use the weak one. At first, child will have a hard time seeing. Their vision will get better, though it might take weeks or months. After that, they won’t have to wear the patch all the time. But sometimes, when kids go back to using both eyes, they lose some vision in the weak eye. If that happens, they might have to wear the patch again.

Eye drops with a medication called Atropine , which blurs the strong eye so your child won’t need to wear a patch. This also forces their brain to use the weak eye.

A Bangerter filter worn over the eyeglass lens of the stronger eye to blur their vision so they have to use the weak eye.

CONCLUSION

Amblyopia may be reversible with appropriate visual stimulation. The detection and management of amblyopia should begin as early as possible. It has been seen that older children and adults with amblyopia also respond to amblyopia treatment. Thus, treatment should be attempted in older children.

Amblyopia should be treated in a stepwise manner. Prescribing an appropriate refractive correction is an initial step when treating amblyopic patients. Patching for 2 hours each day or pharmacologic penalization may be considered as an additional treatment option for amblyopia. If there is no improvement between two consecutive visits, increasing the prescribed patching duration to 6 hours per day could be a reasonable option. Good compliance with prescribed amblyopia treatment is critical for a successful visual outcome. Compliance with amblyopia therapy may be improved by educational programs, direct communication with children and their parents, and increasing the frequency of follow-up visits. Treatment should be tapered and then discontinued with monitoring for amblyopia recurrence. Follow-up visits are required after the treatment to detect any deterioration of vision and provide prompt re-treatment, if necessary.

REFERENCE

1. A Randomized trial of patching regimens for treatment of moderate amblyopia in children.

2. Amblyopia (Lazy Eye), National Eye Institute.

3. Amblyopia- American Association for Pediatric Ophthalmology and Strabismus.

4. Amblyopia: Lazy EYE Diagnosis And Treatment – American Academy Of Ophthalmology.