You may still need glasses or contact lenses after surgery. If you used reading glasses before surgery, you will still need reading glasses after surgery. Results are generally not as good in patients with very small or very large refractive errors. Results may not be lasting. The level of improved vision you experience after surgery may be temporary, especially if you are farsighted or currently need reading glasses.
Some patients lose vision.
Some patients lose lines of vision on the vision chart that cannot be corrected with glasses, contact lenses, or surgery as a result of treatment. Some studies suggest that patients do not see as well in situations of low contrast, such as at night or in fog, after treatment as compared to before treatment. Therefore, patients with low contrast sensitivity to begin with probably should not have a refractive procedure. It is important for you to know that not all eye centers test contrast sensitivity, and that when it is tested, it should be done in a dark room. Some patients may develop severe dry eye syndrome.