In most cases, you should expect that your vision will improve after the surgery and your need for corrective lenses will be decreased or eliminated.
On average, with the LASIK procedure, there is a 90 to 98% chance of achieving 20/40 vision or better. To legally drive without glasses in most states you will need at least 20/40 vision.
There is about a 60% chance of achieving 20/20 vision and about an 85% chance of achieving 20/25 following LASIK. Whether or not this is achieved depends on your current level of correction, your healing response, and if you have had past eye disease, infection, trauma or were born with eye problems.
In general, how well your vision is corrected with contact lenses or glasses is usually the level of correction that LASIK attempts to achieve. It will not achieve a greater level than this.
Some patients do have vision quality problems following a LASIK procedure, such as difficulty seeing in dim light, sensitivity to light, glare, starbursts or halos at night. And some people may be at a higher risk for these symptoms. Your healthcare provider will discuss your situation with you prior to surgery. However, even patients at low risk may notice symptoms after surgery.
These symptoms are most common and noticeable during the first few months following surgery. They tend to diminish over time, and in many patients may not completely go away.
Finally, if you and your doctor are unhappy with your level of vision after LASIK, an enhancement surgery, which is a second surgery, may be performed. This will increase the odds of achieving good functional vision. This is usually necessary in about 10-18 patients out of 100. Patients with high degrees of nearsightedness, farsightedness or astigmatism may be at a higher likelihood of needing an enhancement procedure to achieve their best possible vision.
Because individual situations can vary, if you have any questions about your expected results, you and your doctor can discuss your particular situation. It is important that your expectations match those of your doctor.