Overcorrection
Overcorrection results when the refractive error is changed more than was intended. An initial, or temporary, overcorrection may occur and usually rights itself in the first month. After a treatment for farsightedness, an overcorrection would make you temporarily nearsighted. In this case, your distance vision would be somewhat blurred and your near vision rather good. Following the treatment for nearsightedness, an overcorrection would make it more difficult for you to see objects up close. Patients can manage a temporary overcorrection by wearing glasses until it resolves.
There are fewer permanent overcorrections than permanent undercorrections. A significant overcorrection can be treated with an enhancement procedure as well. An overcorrection enhancement is usually performed 3-6 months after the initial treatment, once the patient’s vision has stabilized.
Induced Astigmatism
In rare circumstances, significant astigmatism results after the initial LASIK surgery. Induced astigmatism causes blurred vision. Most people can tolerate small degrees of astigmatism. However, if your vision is blurred because of a refractive error after LASIK and does not meet your expectations, there is a 99% chance that it can be corrected with enhancement.
Dry Eye
As detailed in earlier posts, it is not uncommon for patients to experience a feeling of dryness or grittiness in the eye after LASIK. This is a common side effect from the surgery that will usually decrease over the first few weeks. The use of nonpreserved lubricating eye drops (artificial tears), punctal plugs, or a medication called Restasis will help alleviate the symptoms of dry eye.
LASIK makes eyes somewhat drier than before surgery. For most patients this is not a problem, because the eyes have more moisture than needed; so a little dryness is not bothersome. However, in rare cases patients develop more significant dryness after LASIK. These patients experience dryness throughout the day. You are more at risk for this if you have dry eyes before LASIK when wearing glasses. (Many people have dry eyes while wearing contact lenses, but this is not a risk factor if the dry eye is treated before the LASIK procedure.) An important part of the comprehensive examination is an evaluation of tears to ensure that your chance of experiencing post- LASIK dryness is minimal. If you do develop persistent dryness, a variety of treatments are now available. These include taking dietary supplements, using lubricating eye drops, using eye drops that improve tear production, and blocking your tear drainage canals with tiny plugs to retain more tears in your eyes.