LASIK Risks & Side Effects

Risks and Side Effects

The overwhelming majority of patients who have had LASIK are extremely satisfied with their results and indicate they would undergo LASIK again if they had the choice. However, as with any surgical procedure, for certain patients the outcome of LASIK may not meet all their expectations. A small percentage of patients experience complications.
It is precisely for this reason that a thorough examination and discussion occur with the surgeon before the procedure. Each patient is informed of the risks and benefits of LASIKand needs to feel comfortable that they are making an educated decision based upon facts.
If you’re interested in LASIK surgery but are worried about the potential risks and side effects, Dr. Kelly will be happy to address your concerns. Please contact us to schedule a free, comprehensive LASIK vision correction consultation.

Important side effects to be aware of are as follows:


The excimer lasers that are used to perform LASIK are highly precise. However, in a small percentage of cases there may be residual nearsightedness, farsightedness or astigmatism after LASIK. Fortunately, these side effects are easily treatable with enhancement procedures typically performed as soon as 12 weeks after the first procedure. The enhancements are used to optimize the visual outcome. Rarely, there may be a mild long-term reduction in results known as regression. Regression may be treated with enhancements or a mild pair of glasses or contacts. On occasion, the cornea may not have sufficient thickness for an enhancement and glasses or contacts may have to be used to optimize vision. Dr. Kelly bases the need for an enhancement on patient satisfaction and relevant medical factors. An enhancement can be performed at almost any time beyond 12 weeks after the initial procedure. In general, the higher the initial degree of visual error the higher the probability of needing an enhancement.

Loss of Best-Corrected Vision:

LASIK cannot provide perfect vision to every patient. An extremely small percentage of patients do not see as well after LASIK as they did with their glasses or contact lenses before LASIK. This may be true even with the use of glasses or contacts or enhancements after LASIK. This may be due to loss of contrast sensitivity. Contrast sensitivity is the ability to distinguish individual objects from one another. It is the distinctness of vision. It usually improves over time. Bear in mind that almost everyone who has undergone LASIK finds their vision to be equal to or better than it was with glasses or contacts before LASIK.


Especially under dim lighting conditions some patients report that the aura around certain lights appears more noticeable after LASIK than before. This condition often improves throughout the healing period. Although highly unlikely, it can possibly affect one’s ability to function at night, such as when driving an automobile.

Dry Eye:

It is very common for the eyes to experience dryness after the LASIK procedure. Dryness is usually described as an uncomfortable scratchy and sandy feeling in the eyes. It is temporary in the overwhelming majority of cases but may be chronic in a tiny percentage. It is treated with artificial rewetting drops among other methods.


This is an age related vision change and not a LASIK complication. It is the gradual loss of ability to focus on near objects. Presbyopia typically begins at around age 40-45 and progresses into the 60s. LASIK does not correct presbyopia. Presbyopia is usually corrected with over-the-counter reading glasses to see near objects. Monovision is a technique that can be used with LASIK where one eye is corrected to see distant objects and the other eye is corrected to see near objects. It dramatically reduces a presbyopic person’s dependence on reading glasses. However, it usually decreases one’s depth perception and peripheral vision. Monovision is considered by many to be a viable compromise to correct distance and near vision for the person with presbyopia. Dr. Kelly usually has patients considering monovision undergo a trial with contact lenses before the procedure.

Fluctuating Vision:

It is common for vision to fluctuate during the first few weeks to months after laser vision correction. One may experience episodes of clear vision combined with intermittent episodes of blurry or hazy vision. Light sensitivity is common. All of these side effects diminish with time.

Red Patches:

It is also common for red spots to be present over the white parts of the eyes for a several weeks after LASIK. They completely resolve and are harmless.

Corneal Scarring:

This is one of the most dreaded complications after LASIK but is extremely rare. It can be the result of infection or flap problems. There have been cases where scarring has caused very poor vision requiring cornea transplant for treatment.
Please keep in mind that vision threatening complications are extraordinarily rare. Most side effects resolve over time and can be treated successfully.
The healing process is an important determinant in the final result. Everyone heals in an individual manner that is not always predictable. Healing determines, in part, the speed of recovery, the sharpness of vision, and the likelihood of the need for an enhancement. The medications Dr. Kelly prescribes assist in the healing process after LASIK should be used according to the instructions. As a general rule, the higher the initial visual error the longer the healing.
It is important that anyone considering laser vision correction have realistic expectations. People looking for perfect vision after LASIK run the risk of being disappointed. Dr. Kelly is proud that 99% of his patients achieve vision within 2 lines of 20/20. In his experienced hands, using the best technology, success is likely but not guaranteed.

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