subject: An Outline of Kinds of Refractive Errors and Their Treatments [print this page] An Outline of Kinds of Refractive Errors and Their Treatments
Refractive errors in modern society are a rather commonly seen eyesight problems. You could even find 7 to 8 people having one refractive error out of 10. Then what is a refractive error? It is a condition of the eye in which a clear image fails to focus on the retina due to optical causes. They briefly include myopia, hyperopia and astigmatism.
Myopia, or nearsightedness we usually referred as, results from the out focus of light rays on retina. Myopia patients would feel hard to see objects clearly in the distance, but there is no problem to view object at near clearly. Hyeropia, or farsightedness, is opposite to myopia. Patients concerned would have a clear vision at the distance but blurred vision at near. The light rays do not converge or focus by the time they reach the retina. Astigmatism is different from the former two, patients with astigmatism would find it hard to view both far and near, and double images are possible. Other symptoms may include difficulty in reading or seeing up close and crossing of the eyes in children. It can be classified into regular one, mixed one and irregular one.
Up to now, the most effective treatment for those refractive disorders should be Lasik, an eye surgery performed by a special laser. It achieves to correct nearsightedness, farsightedness and astigmatism by reshaping the shape of cornea. When you get into the operating room, the surgeon would firstly ask you to lay on the operating table and then give some anesthetic eye drops to your eye, so that you will feel no pain during the procedure. After the anesthetic works, the surgeon would use a microtome to create a thin corneal flap so that the laser would sculpt layers of the remaining cornea to change its shape. How much tissue will be removed depends on the degree of nearsightedness, for example, that is being corrected. After the reshaping procedure, the surgeon will put back the flap. Don't be worry that any scar will be left, for the flap is created in the cornea and it conforms to the underlying surface.
One of the biggest advantages of Lasik is that the patients would see clearly immediately after the surgery, and they can go back home after some time's rest. This is one of the reasons why Lasik is so popular now in refractive errors correction.
