A cataract is a clouding of the normally clear and transparent lens of the eye which is located behind the pupil. When the lens becomes cloudy from age, injury or a birth defect, less focused light reaches the inside of the eye and vision gradually fails.

Symptoms of cataract range from a barely noticeable loss of vision to virtual blindness. The first symptom may be difficulty in performing routine tasks. Fuzzy or blurred vision, frequent changes in glasses, double vision in one eye, problem in reading, decreased color perception and poor night vision are common symptoms. Night driving may be a particular problem. Vision may fluctuate from normal to almost complete blindness under bright light or glare conditions.

A medical eye examination, including a check for glasses (refraction), is necessary. In early stages of cataract, a change in glasses may be all that is necessary to improve vision. During the examination, your ophthalmologist will determine if there are other causes of vision loss. The usual test for vision, the letter eye chart, may not reflect the true extent of your visual loss.

Most Cataracts associated with ageing progress slowly. Some patients do not notice the extent of their visual loss because of the slow onset. Other Cataracts, especially in younger people and patients with systemic disease such as diabetes, progress rapidly over a few months and vision deteriorates quickly. It is not possible to predict exactly how fast cataracts will progress in any given patient.

Surgery is the only effective way to remove a cataract. When Cataract causes enough loss of sight to interfere with your work or lifestyle, it is time to remove it them. The ability to safely operate a motor vehicle is a consideration for some people. Your ophthalmologist and you should decide together when surgery is desirable.

Surgery is not necessary just because a cataract is present. Symptoms may be mild and well tolerated. On the other hand, there is seldom a need to delay surgery when vision loss from a cataract interferes with your daily activities. It is a misconception that cataracts need to be "ripe" before removing them. Surgery can be performed whenever visual needs require it. Surgery can be performed in any season.

The belief that winter is the best time for cataract surgery is a myth. It really does not matter whether it is summer, winter or monsoon. The belief probably started when large incisions were required for surgery and the patients had to lie immobile for many days.

Another misconception is that a cataract should only be operated after it is ripe. This was true with older techniques, but today with the modern phacoemulsification technique of cataract surgery, the opposite is true. Waiting too long for a cataract to mature can sometimes increase the risks of surgery.

Before intraocular lenses were invented, people had to use spectacles on an average of +10.0D for distance and +13.0D for near. The quality of vision with these spectacles was very poor. This grossly hampered the life style of these patients. With intraocular lenses, you will end up with a nominal near and distance power. Still, if you want to further reduce your dependence on glasses, multifocal intraocular lenses will give you good near and distance vision without glasses, and you will need glasses only for every fine work.

Cataract surgery is a highly successful procedure. Useful vision is restored in over 90% of the cases. However, it is important to understand that complications can occur. As with any surgery, a good result cannot be guaranteed always.

There may be other reasons for visual loss in addition to the cataract, particularly problems involving the retina or optic nerve. If these conditions are severe, removal of the cataract may not result in any visual improvement. An examination by an ophthalmologist can help to predict whether visual improvement is likely or not.

With Cataract Surgery the best second opinion is often your own, since you are in the best position to determine how much your cataract interferes with your daily activities. However, if a second medical opinion is required or you feel that recommended cataract surgery may not be necessary, a second opinion may be obtained from another ophthalmologist. Since the timing of cataract surgery is a personal matter, there is no right or wrong opinion, and ophthalmologists may have differing recommendations.

There are two circumstances in which removal of a cataract should be considered even though improvement in vision may not be expected.

A cataract may be so advanced that diagnosis or treatment of other eye disease cannot be performed properly. In this situation it may be best to remove the cataract so the interior of the eye can be examined.

It is also possible for a Cataract to become so advanced that the cataract itself causes other eye disease, particular inflammation; these are only ones in which cataract removal may be considered an emergency.

Because a Cataract is a clouding of, and not a film over, our lens, it cannot be treated with eye drops. Surgery is the only way to remove a Cataract. Surgery involves removal of a cloudy lens then replacing it with artificial Intra Ocular Lens. Previously a large incision was made (10-12 mm) and the cataract was removed. Now, a new technique known as phacoemulsification is done to remove the cataract and before cataract surgery, A-scan (Sonography) of both the eyes are to be done to measure the strength (power) of the artificial lens to be implanted.

On the day of the surgery, the patient will be instructed not to eat or drink anything for few hours. A mild sedative is to be given before surgery to help the patient relax. General anesthesia is given to children or those who require or request it. A local anesthetic is then given either as eye drop alone or in combination with injection around the eyeball. Patients are usually awake, relaxed and comfortable during the surgery. Cataractous lens is then removed by phacoemulsification and replaced by intraocular lens implant.