Most focusing problems are due to the shape of the eye. If the cornea is too steep or too flat in curvature, this can create short-sightedness or long-sightedness and other distortions in vision.
What we do with laser vision correction, is use a special laser to smooth off and reshape the surface of the eye to correct those focusing problems.
Although it may seem rather inconsequential, it is in fact a highly organised tissue. Unlike most tissue in the body, the cornea contains no blood vessels to nourish or protect it against infection. Instead, the cornea receives its nourishment from tears and the aqueous humor (a fluid in the front part of the eye that lies behind the cornea). Small scratches or minor injuries it can handle.
However more serious injuries, some allergies, a few inherited conditions and a raft of diseases with increasingly bizarre names may make surgical intervention (corneal transplantation) necessary.