Cataracts are a condition in which the lens of the eye (crystalline lens) becomes cloudy or opaque. It becomes difficult to focus on objects and things seem dark to the person.
The whitish or opaque appearance indicates a change in the lens fibers. It is similar to the change in color of an egg white when it is cooked.

Symptoms : progressive loss of vision, no pain but some sensitivity to light.
Sometimes you can see a radiance around points of light.

Causes : The most common causes are :

• Diabetes and the combination of drinking large quantities of milk and not being able to process galactose, which is a sugar abundant in milk.
• Deposits of calcium and cholestrol in the capillaries of the eyes which reduce blood circulation to the eyes.
• They can also be caused by a blow or injury to the eye, and by inadequate nutrition.
• Too much sun tanning can cause cataract since the sun's ultrviolet rays cloud the crystalline lens causing opacity of the lens. The effect light produces on the lens is similar to that of heating an egg white, it becomes opaque. Cataracts also seem to be part of the normal aging process. Also, exposure to X-rays can cause them.

It is the result of high pressure inside the eye. It normally occurs in adults.

There are two types of glaucoma :
Acute glaucoma is when there is suddenly a strong pain inside the eye. Vision becomes cloudy and the eye turns red. The pupil of the affected eye becomes larger than the one of the good eye and the eye feels very hard to the touch. If the pain does not stop within 24 hours, seek an opthalmologist's help. Surgery may be required in order to drain the eye and relieve the pressure.

Chronic glaucoma occurs slowly and it's symptoms are not generally felt. It's symptoms are : Gradual loss of eye sight usually affecting the peripheral vision first.
This is a dangerous disorder which may cause blindness, therefore immediate medical care is recommended.

Causes may be due to diabetes, arterisclerosis or high blood pressure.