Page 56 - NAME OF CONDITION: REFRACTIVE ERRORS

NAME OF CONDITION: CATARACT

I. WHEN TO SUSPECT/ RECOGNIZE?

a) Introduction:
Cataract is the commonest cause of blindness and visual impairment in India. It affects a

significant number of elderly people’s quality life and economic productivity. This age
related condition usually presents with gradual dimness of vision in both eyes. In the earlier
stages, patients may experience glare, especially while driving at night. There may be
monocular diplopia or polyopia, reduced contrast sensitivity and altered colour perception.
Over a period of time, the cataracts can advance and can cause total blindness.
Very rarely, children can also have cataract. These children are born with this disorder or
develop it at a very early age. The definitive treatment is always surgery with a very
favourable risk reward ratio. In fact, cataract surgery is one of the most cost-effective
public health interventions worldwide.

b) Case definition:
A cataract is any opacity of the crystalline lens or its capsule leading to degradation of its
optical quality, thereby causing decreased quality of vision.

II. INCIDENCE OF THE CONDITION IN OUR COUNTRY

In India cataract has been reported to be responsible for 50-80% of the bilaterally blind in
the country .Data from a population based longitudinal study of randomly selected
communities in Central India have for the first time provided direct estimates of age

specific incidence of blindness from cataract. It estimated that 3.8 million persons become
blind from cataract each year in India. The absolute number of cataract blind which was
7.75 million in 2001 is likely to reach 8.25 million in 2020 due to a substantial increase in
the population above 50 years in India over this period.

The 60+ population which stood at 56 million in 1991 will double by 2016.This increase in
population means that the population 'at-risk' of blinding cataract will also increase
tremendously. The economic loss due to blindness and visual disability from cataract is
enormous. Cataract blind people are unable to work and thus due to lack of productivity,
the economic impact is a staggering 4.5 million rupees per year of every million population.
Cataract in children, although rare, can still happen. The prevalence of blindness among
children in different regions varies from 0.2/1000 children to over 1.5/1000 children with a
global figure estimated at 0.7/1000. In India this figure is approximately 1 per 1000

children. The proportion of blindness in children due to cataract varies considerably
between regions from 10%-30%. Children who are blind have to overcome a lifetime of

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