Cataract

What is a cataract? 

A cataract is an opacification of the natural lens. this can happen as natural process due to aging, or it can happen because of trauma to the eye. it can be congenital (some children are born with a cataract), or be due to a systemic, metabolic process (for example, people with Wilson's disease, who cannot metabolize copper, have copper-associated "sunflower cataracts")

a cataract is "visually significant" if you cannot do your activities in life because of the cataract. for example, your vision is so blurred that even with glasses, you cannot drive, or read. at this point, the cataract needs to be surgically removed.

There are two types of surgery that are predominantly done. the most common form in the US is phacoemulsification. In this kind of surgery, a small incision is made in the cornea (the front part of the eye), and a hole is made in the anterior capsule of the lens. the cataract is then divided into small pieces and removed using ultrasound energy. an artificial lens is then placed in where the old lens resided.
if you have significant astigmatism, you may be a candidate for an astigmatism correcting lens.

the other type of surgery is called small incision cataract surgery, which is the most common form South Asia and East Africa. here, a 6-7mm scleral tunnel is made, an opening is made in the anterior capsule, and the lens is removed in its entirety using a lens loop or similar instrument. an artificial lens is placed where the old lens resided.