Living in the tropics such as Indonesia should have become a habit to always wear sunglasses when the sun is hot. Sunglasses powerful enough to protect the eyes from ultraviolet radiation. These rays can be very damaging, even if the eye in a short time.
Quoted from HealthDay, Tuesday (08/24/2010), the risk of short-term damage that could be prevented with sunglasses include burning eyes (photokeratitis). Damage is characterized by inflammation of the cornea, which if left unchecked can cause cell death in that section.
Such inflammation can also occur on the conjunctiva, the white part of the eye. Although painful, inflammation in both parts could still be and easy to cure.
As for the long term, damage from ultraviolet rays can accumulate and lead to more serious disorders. Among these are as follows:
Pterygium
Is an abnormal growth of the conjunctiva or white part of the eye, which can be caused by too much exposure to sunlight. This abnormal growth will damage the cornea, which interfere with vision.
There is no other way to overcome these problems except by surgery. And even then still leaves a chance of recurrence, because that is damaged conjunctiva basically difficult to regenerate.
Cataract
In patients with cataracts, the lens color is clear turn into turbid thereby blocking the incoming light. Ultraviolet rays emitted by the sun thought to be one major cause of this disorder.
Setbacks function of the macula (macular degeneration)
Ultraviolet rays can also damage the retina, the thin layer at the back of the eye that serves catch the light. The damage also affects the macula functions, namely the center of the retina as well as central vision.
Cancer
The surface of the eye can develop melanoma, a type of malignant cancer caused by ultraviolet light which requires surgery to fix. Whereas in the eyelids, the sun also causes the risk of basal cell carcinoma.
source: (http://www.detikhealth.com/read/2010/08/24/121634/1426575/766/kerusakan-mata-akibat-tidak-pakai-kacamata-hitam)