Cataract surgery involves removing the natural lens of the eye and replacing it with an artificial lens (intraocular lens implant or IOL). The plastic artificial lens is permanent, requires no care, and can significantly improve vision.ataract surgery is indicated when the cataract impairs vision to the extent that it interferes with normal daily activities. Cataract extraction is one of the most frequently performed surgical procedures in the world. A cataract is a cloudy or opaque area in the normally clear lens of the eye.
There are 640 acres in a square mile -- there is no such thing as a square acre. And just in case you are interested, 43560 square feet in an acre. idiot detector Â· 1 decade ago
It should not be confused with miles square, which refers to the number of miles on each side squared. For instance, 20 miles square (20 Ã 20 miles) is equal to 400 square miles; an area of 10 Ã 40 miles is likewise 400 square miles, but it is not 20 miles square. One square mile is equal to: 1  4,014,489,600 square inches. 2  27,878,400 square feet. 3  3,097,600 square yards. 4  640 acres. 5  2560 roods.