LASIK is a laser eye surgery that reshapes your cornea to correct nearsightedness, farsightedness, and astigmatism. The procedure takes about 15 minutes for both eyes, and more than 90 percent of patients end up with 20/20 vision or better. It’s the most common elective vision procedure in the world, with a 96 percent patient satisfaction rate.
How LASIK Corrects Your Vision
Your cornea is the clear, dome-shaped front surface of your eye. It bends incoming light so it lands on the retina at the back of your eye, which is how you see a focused image. In nearsightedness, the cornea bends light too much. In farsightedness, not enough. In astigmatism, it bends light unevenly. All three problems come down to the cornea’s shape not matching the length of your eye.
LASIK uses an ultraviolet laser to vaporize a precise, microscopic layer of corneal tissue, permanently changing the cornea’s curvature. This reshaping redirects light so it focuses cleanly on the retina. The cornea ends up slightly thinner afterward, which is why your surgeon will measure corneal thickness beforehand to confirm there’s enough tissue to work with safely.
What Happens During the Procedure
The surgery has two main steps: creating a flap in the outer cornea, then reshaping the tissue underneath.
First, your surgeon creates a thin, hinged flap on the surface of your cornea. This can be done with a precision blade (called a microkeratome) or with a femtosecond laser. The femtosecond laser works by firing ultrashort pulses of energy that create thousands of tiny microscopic bubbles at a specific depth in the cornea. These bubbles define a separation plane, essentially outlining the flap without a blade. The blade method is faster, taking less than 30 seconds, while the laser method offers more precise control over flap thickness and placement.
Once the flap is folded back, the excimer laser removes tissue from the exposed inner cornea in a pattern customized to your prescription. The flap is then laid back into position, where it adheres naturally without stitches. The entire process is painless because numbing drops are applied beforehand, though you may feel mild pressure.
Who Qualifies for LASIK
LASIK can correct up to about 12 diopters of nearsightedness, 6 diopters of farsightedness, and 6 diopters of astigmatism. Your prescription also needs to have been stable for at least a year before surgery. People in their early 20s or younger often don’t qualify because their vision is still changing.
Several conditions can rule you out. Keratoconus, a condition where the cornea progressively thins and bulges, is a firm disqualifier. Autoimmune diseases like lupus or rheumatoid arthritis, immunodeficiency conditions like HIV, and diabetes can all interfere with healing. Certain medications, including steroids and retinoic acid, pose similar risks. If you’re pregnant or breastfeeding, hormonal fluctuations can temporarily shift your prescription, so you’d need to wait.
Other factors that raise red flags include thin corneas (removing tissue from an already-thin cornea risks serious complications), chronic dry eyes (LASIK tends to make them worse), a history of eye infections like herpes simplex involving the eye, glaucoma, and previous eye surgeries. Large pupils can also be a concern because they increase the chance of halos and glare at night. Your initial consultation will include detailed measurements of your corneas, pupil size, and overall eye health to determine if you’re a good candidate.
Recovery Timeline
Most people notice dramatically improved vision within hours of surgery, but full stabilization takes longer. In the first day or two, you’ll wear a protective eye shield, especially while sleeping, and return to your surgeon for an exam within 24 to 48 hours. Light non-contact activities like jogging can resume within one to three days.
For the first two weeks, avoid lotions, creams, and makeup around your eyes to reduce infection risk. Contact sports like football, boxing, or martial arts are off-limits for at least four weeks. Swimming, hot tubs, and whirlpools should wait one to two months.
Your vision may fluctuate during the first few months. It typically takes three to six months for your eyesight to fully stabilize, which is why surgeons wait at least three months before considering any touch-up procedure.
Side Effects and Risks
The most common side effects are dry eyes and visual disturbances like halos and glare around lights. An FDA study found that up to 28 percent of people who had no dry eye symptoms before LASIK reported them at three months post-surgery. Up to 40 percent of people who had no halos before surgery experienced them at the three-month mark. For most patients, these symptoms improve over the following months as the eyes heal.
Serious complications are rare. Less than 1 percent of participants in the FDA study reported “a lot of difficulty” performing everyday activities without glasses due to visual symptoms like starbursts, ghosting, halos, or glare after surgery. The more consequential risks, such as infection, chronic pain, or significant vision loss, occur in a very small fraction of cases.
Long-Term Results and Regression
LASIK delivers strong results that hold up well, though your eyes can still change over time. A 10-year follow-up study found that about 36 percent of treated eyes eventually needed a retreatment (called an enhancement). This doesn’t mean the original surgery failed. Natural age-related changes in the eye, separate from the reshaped cornea, can gradually shift your prescription. The initial correction from the study remained largely intact at the 10-year mark, with only a slight decrease from the best results measured at one month.
Presbyopia, the age-related loss of near-focus ability that typically starts in your 40s, will still happen regardless of LASIK. It’s a stiffening of the lens inside your eye, not a corneal issue, so LASIK doesn’t prevent it. Most people who had LASIK in their 20s or 30s will eventually need reading glasses.
Types of LASIK Technology
Not all LASIK treatments use the same laser programming. The main approaches differ in how they customize the reshaping pattern to your eye.
- Wavefront-optimized LASIK corrects your basic prescription while minimizing the introduction of new optical imperfections. This is the most widely available version.
- Wavefront-guided LASIK goes a step further by also correcting subtle pre-existing optical imperfections unique to your eye, not just your glasses prescription.
- Topography-guided LASIK maps the surface irregularities of your cornea and smooths them out in addition to correcting your prescription. It tends to use slightly less tissue, which can be an advantage for people with thinner corneas.
Clinical comparisons show that for straightforward prescriptions like mild to moderate nearsightedness with astigmatism, all three approaches produce similar safety and visual outcomes. Topography-guided treatments take slightly longer during the laser phase, but the end results are comparable. Your surgeon will recommend a specific technology based on your eye measurements and prescription complexity.
Cost of LASIK
The national average cost is about $4,500 for both eyes, or roughly $2,250 per eye. This price typically includes the surgery itself, pre-operative diagnostics, follow-up visits, and sometimes even enhancement procedures if needed later.
You may see advertisements for LASIK at dramatically lower prices, sometimes under $1,000 per eye. These deals usually apply only to very mild prescriptions and may not include follow-up care, medications for healing, or the most current laser technology. When comparing prices, ask what’s actually included: pre-surgical testing, the specific laser platform being used, post-operative visits, and whether enhancements are covered.
LASIK is considered elective, so most health insurance plans don’t cover it. Many practices offer financing plans, and some employers provide flexible spending or health savings accounts that can be used toward the cost.