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II. INCIDENCE OF THE CONDITION IN OUR COUNTRY

There are not many reports available from India about the prevalence of strabismus. One
population based study from South India reported the prevalence as 0.43% among
children. Another study in North India among school children reported it as 2.5%. The
presence of strabismus is not a cosmetic issue only. Its presence says that the child is
unable to use both eyes together and there could be some other ocular problem that is
undetected.
Different studies from developed countries on amblyopia have an estimated prevalence in
childhood of 1.2% to 4.4% depending on the defining criteria.

III. DIFFERENTIAL DIAGNOSIS

Strabismus

 Pseudostrabismus
 Nystagmus
 Facial asymmetry
Amblyopia
 Nutritional/Toxic optic neuropathy
 Malingering

 Cortical blindness

IV. PREVENTION AND COUNSELING

Recent studies have shown that early detection and treatment of amblyopia are highly cost
effective when compared with other interventions in health care. The earlier amblyopia is
detected and properly treated, the higher the likelihood of visual acuity recovery. Starting

treatment at a young age also may increase the likelihood of compliance and the rate of
vision recovery. The Amblyopia Treatment Study demonstrated that more than 75% of
amblyopic children younger than 7 years can have significant improvement in the
amblyopic eye (to 20/30 or better) as the result of treatment. The purpose of periodic eye
and vision screening is to detect pediatric eye disorders, especially amblyopia, at a
sufficiently early age to allow effective treatment. All children should undergo eye and
vision screening, because screening is most effective when performed periodically
throughout childhood.

In addition, children with risk factors for amblyopia should have a comprehensive
ophthalmic evaluation. Some risk factors include family history of amblyopia or strabismus,
childhood cataract or glaucoma, premature birth of less than 30-week gestation or 1,500
grams, and delayed visual or neurologic maturation of unclear etiology. Reduction or

prevention of risk factors such as premature birth and detrimental prenatal environmental

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