Long Term Visual Outcomes

LONG TERM VISUAL OUTCOMES: Technology does not yet allow us to predict a person's speed and degree of corneal healing, both of which affect the final visual outcome.

Undercorrection.This means the cornea gets less effect from the laser than desired, due to overhydration of the cornea intraoperatively or, more likely, from too aggressive of a healing response afterward. The eye is left with a slight residual prescription. This result is more common with high prescriptions. If necessary, once the vision is stable, usually at about 3-4 months, the flap can be relifted and touched up with the laser.

Overcorrection.This means the cornea gets more effect from the laser than desired, due to dehydration of the cornea intraoperatively or, more likely, from too slow of a healing response afterward. The eye is left with a slight unintended overcorrection. However, if you have a higher prescription, you will be intentionally overcorrected at first, because your vision will drift more as you heal.

Possible Loss of Best Corrected Visual Acuity.If you are correctable to 20/20 or 20/15 before the surgery, you will likely be correctable to the same afterwards. However, in rare circumstances, the best visual acuity attainable (with lenses) afterwards can be less than before, but not to a degree as to interfere with daily activities. Statistically, over 99% of patients that are correctable to 20/20 see at least 20/20 after. Approximately 3-4% actually see a line or two better. Less than a fraction of 1% lose ability to see a line or two, but most commonly these are patients who saw 20/15 before surgery and "only" see 20/20 after. Since both eyes work together, this is rarely a perceptible loss, and definitely not an impediment to activities.