Astigmatism is the inability to focus clearly at any distance. With astigmatism the cornea is shaped more like a football than a basketball. LASIK
corrects this oval shape, making the cornea more round and achieving clear vision.
Nearsighted people see close objects clearly – but not distant objects. In nearsightedness, the curve of the cornea is too steep and images are focused in front of the retina. LASIK
corrects this condition by flattening the curve of the cornea.
Farsighted people see distant objects clearly, but all other objects are blurred. In farsightedness, the shape of the cornea is too flat and light rays are focused behind the retina. LASIK corrects this condition by shaping the cornea so that it focuses correctly.