Cataract



Visual field with cataract


A cataract occurs when the crystalline lens opacifies, which prevents light from passing through. Vision gets blurred, the perception of colors is dulled, and the eye becomes very sensitive to light. It generally appears in persons aged over 60. This disease may also affect young children; in such cases the cataract is said to be congenital.

Symptoms

    • Reduction in contrast 
    • Sensation of glare 
    • Discomfort engendered by luminous halos at night 

Did you know?
> Cataract is number 1 cause of blindness, accounting for 16 million people worldwide(1).
> 3 million cataracts cases worldwide may be caused by sun exposure(1).

> 80% of a person's lifetime UV exposure is received before the age of 18(1).

Sun exposure and cataract

Many studies show a strong correlation between cataracts and UV exposure (2)(3). 
 
Moreover with the depletion of the Ozone, we should expect an increase of UVB and an increase in cataracts. A 10% decrease in Ozone leads to an increase of 1.6 – 1.75 million cataract cases(4)


The best line of defense against UV for photo-induced eye disease is still the wearing of eyeglasses with 100% UV protection.(5)

(1)Muller A Hugh R., Sun Protection in children and adolescent knowledge vs behaviortaylor Point de Vue 56, (2007), 9.
(2)Tomany S.C., Cruickshanks K.J. Klein R., Klein B.E. Kundston M., Sun Light and the 10 year incidence of age related maculopathy Arch Ophtalmol 122, (2004), 750.
(3)Taylor H.R., Ultraviolet Radiation and the eye an epidemiologic study, Tr.Am.Opht Soc. (1989), 802
(4)Protecting children from ultraviolet radiation Fact sheet Nr 261 Geneva, WHO (2001).
(5)Barker FM, Point de Vue 59 (2008) 27.