The doubly convex, transparent body situated behind the iris in the eye that focuses the image of outside objects on the retina, is called a crystalline lens. Cloudiness of this lens for any reason is called cataract.

Cataract can be:

1. congenital

2. traumatic

3. due to diseases of the eye

4. due to systemic disease

5. caused by medication

6. or simply from old age.

Most cataracts can be taken care of, and a good, clear can be vision restored. Although there are rare complications which can occasionally be quite serious, advanced technology make it possible for well-trained ophthalmologists to perform surgery with satisfactory results. Traumatic and congenital cataracts or those that are caused by intra-ocular pathology can be challenging to the surgeon and in some cases visual outcome will not be as good as senile cataract.

In senile cataract, the process leading to cloudiness of the lens is a natural one. The central structural fibers of the lens are gradually pushed towards the center, becoming compressed and dense (nuclear sclerosis) and the lens will look yellowish or even brown-ish, making the lens less transparent. Along with this change there may also be coagulation of the proteins of the lens to further reduce the clarity. All these changes, of course, will make the lens less clear and cause blurry vision. Everybody will develop cataract if they live long enough. Minimal clouding of the lens or the more peripherally located opaque spots in the lens may not cause visual problems and need not cause apprehension.

The remedy for the cataract, except in some rare cases, is surgery. The time for surgery in old-age cataract is relative to the progression of the disease and the nature of the person’s visual demands. Usually when the visual acuity of the person deteriorates to the level of 20/40, most eye surgeons recommend surgery, but depending on the person’s visual requirements, surgery can either be performed earlier or be postponed. The eye doctor will discuss the situation with the patient and then he or she, mutually, will decide when to go ahead with the surgery. Very advanced and dense cataracts are harder to chip and remove, therefore timely surgery is recommended. The surgeon will take ultrasound measurements of the eyeball to determine the prescription of the implant to be inserted during surgery.

Cataract surgery is the most common surgery done in the world. The technique of surgery uses fine ultra-sound vibration to fragment the lens into very small pieces, and irrigating/suctioning with a pump until the whole lens material is out of the eye . For fragmentation of lens material different techniques can be used. Next an artificial lens is inserted through a small opening in the cornea by a syringe into the space (bag) behind the iris .
The procedure Is painless, and usually takes about half an hour to complete, and the patient can go home the same day. Usually eye doctors check the eye one and three days after the surgery to make sure there is no elevated pressure, no sign of infection, retinal detachment or bleeding, which can occur sometimes. If the pressure has spiked, eye drops will be used, and in majority of cases, pressure will subside within one or two weeks. The most worrisome complication is the infection inside the eyeball and the treatment of this condition is a real challenge for the surgeon. The infection will result to some degree of vision loss, but this complication (endophthalmitis) is very rare.

Sometimes, months after surgery the bag into which the implant is inserted becomes cloudy due to opacification of its posterior membrane. This will cause fogging of the vision noticeable to the patient, and the eye doctor will suggest putting laser to the cloudy membrane to polish and sharpen the vision again.