Most of common eye diseases of the world , Cataracts are one of them. Cataracts are the most common cause of vision loss in people over age 40. It is the principal cause of blindness in the world. It may develop after eye injuries, inflammation, and some other eye diseases.
What is Cataract ?
Any opacity of the lens or its capsule, causing visual impairment is called Cataract
Classification of Cataract : No classification of cataract is entirely satisfactory. It may be classified as follows:
· Senile Cataract
· Traumatic Cataract
· Childhood Cataract
· Complicated Cataract
Senile Cataract : The ageing lens tends to become apaque after the age of 50 years, and by the age of 70 . Over 90% of the population show some evidence of cataract. It occurs equally in men and women , and is usually bilateral, but often develops earlier in one eye than the other .
Traumatic cataract : May be either due to a concussion or penetrating injury.
Childhood cataract : It means cataract that presents at birth, or develops soon after the birth.. So it is two kinds :
1.Congenital cataract
2.Developmental cataract
Complicated cataract: Complicated Cataract results from a disturbance of the lens metabolism due to inflammatory or degenerative disease of the eye, such as iridocylitis, choroiditis, high myopia, retinitis pigmentosa, retinal detachment etc.
Others cataract :
Anterior polar cataract : It is sharply demarcated opacity of the anterior lens capsule and usually the size of pins head .
Posterior Polar cataract ; This is due to delayed formation of the anterior chamber, during development of the lens.
Coronary cataract : This is the type of development cataract accruing of puberly.
Zonular cataract : It may be congenital or occurs within the first year after birth.
Rubella cataract ; Rubella infection during pregnancy may cause wide spread ocular and systemic defects.
What Causes Cataracts?
· Prolonged use of corticosteroid
· Prolonged exposure to sunlight or radiation
· Eye Injury
· Diabetes
· Smoking
· Excess alcohol use
Symptoms: · People with cataracts may have the following symptoms:
· Blurry, shady, or hazy vision
· Glasses need to be changed more frequently
· Eventually wearing glasses turns out to be less compelling
· Vision may be influenced by little spots or dots.
· The patient sees small patches that blur parts of the field of vision
· Vision worsens when lights are dim
· Vision is sometimes worse when there is very bright light, or glare
· Some people with cataracts also comment that colors appear less clear and blurred
· Rarely, the person may see a radiance around bright objects, for example, auto headlights or road lights, or have double in one eye.
Treatment: The cataract is removed by surgical operation, called extraction of lens. This surgery is a routine operation nowadays and the most common kind of eye surgery.