Is Lasik more effective on short or farsighted patients?
LASIK is predominantly a treatment for near/short-sightedness, i.e. blurry vision far off. While it is possible to treatment certain types of farsightedness (difficulty with vision up close), LASIK does not directly treat the most common type (presbyopia). Rather it makes an "end run" around it by putting the focus of one eye up close and the other far off. LASIK treats only the cornea, while presbyopia is caused by age-related changes of the natural lens inside the eye. Furthermore, the beneficial effects of LASIK on farsightedness are not nearly as long-lasting as for nearsightedness because the natural lens continues to age, undermining whatever effect was originally achieved.