Causes of blindness

A serious eyesight disorder - blindness has many causes:

Eye diseases

Sight disorder is usually caused by diseases and malnutrition. Majority of general causes of blindness in the world are:

• Cataracts – (43%)
• Glaucoma – (15%)
• Trachoma – inflammation of conjunctivas or cornea (11%)
• Avitaminosis – vitamin deficiency in children under 5 years (2%)
• Coloboma – congenital hole in specific eye tissues (3%)

People in developing countries suffer from eyesight disorder more often due to the conditions which could be prevented. Whereas eyesight disorder is everywhere more common in people older than 60 years, the children from poor regions will suffer a lot more from eye diseases than the children living in developed countries.

The connection between poverty and treatable eyesight disorder is expressed finely when we compare the regions. The most of eyesight disorders in adults from North America and Western Europe arise in connection with senile macular degeneration and diabetic retinopathy. Even though both of these diseases can be treated with medicine, at the moment none of them is curable.

Abnormalities and injuries

Eye injuries, which are the most common in people under 30 years of age, are the main cause of monocular blindness (the loss of sight in one eye). Injuries and cataracts affect the eye itself. Abnormalities (e.g. optic nerve hypoplasia) affect the nerve bundle, which transmits signals from the eye to the posterior part of the brain, and can lead to the decrease of vision sharpness. Injuries of the occipital lobe can cause blindness even when the eyes or optic nerves are not damaged.

Genetic defects

People with albinism often suffer from the eye disorder in such extent that many of them are practically blind even though only couple of them is completely without the sight.