Lasik can effectively correct up to 4.00 dioptres (400 degrees) of farsightedness. Farsightedness is the optical opposite of myopia (nearsightedness). It is caused by a shorter than normal eyeball length or flatter than normal cornea curvature.However, it is important not to confuse normal farsightedness with an aging condition called presbyopia or middle-age farsightedness. This is a different condition that afflicts those past the age of 35 years. Presbyopia is caused by the reduced ability of the eye to focus for near as a person grows older. Lasik will NOT do away with the need to wear reading glasses for this condition. In fact, those 35 years and above may find that after Lasik, while they can now see perfectly well for distance, reading glasses may be required for reading
