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In modern LASIK eye surgery, serious complications are rare. Several large studies have demonstrated LASIK complication rates of less than 1 to 1.8 percent. However, there are some potential problems to know if you are considering LASIK.
LASIK, which stands for laser-assisted in situ keratomileusis, is a refractive eye surgery. This procedure can correct astigmatism, nearsightedness (myopia), and farsightedness (hyperopia).
Also, not everyone is a good candidate for LASIK. If you have any of the following medical conditions, laser eye surgery is likely not an option:
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Common complications of LASIK surgery that are low risk include:
This means your vision is not entirely corrected. However, having a small overcorrection or undercorrection is not uncommon. If you are satisfied with your vision and can see clearly, retreatment is not necessary.
However, if you are not happy with your vision, the surgeon may be able to retreat you or prescribe glasses and contacts to correct your vision.
Regression occurs when your vision worsens after receiving LASIK. Regression is related to changes in your eye, such as your natural lens or the length of your eyeball.
Only 1 to 2 percent of patients require an enhancement procedure during the first year after LASIK. Studies show that about 10 percent of patients experience some regression after ten years. Also, keep in mind that normal age-related changes may affect your vision.
Irregular astigmatism is an unequal curvature of your cornea, which causes visual distortion. Common symptoms include glare, halos, starbursts, and ghosting or shadows around images. A second procedure may be necessary to correct irregular astigmatism.
Decentration is when the laser is not centered correctly on the eye during surgery. This can cause irregular astigmatism and may require retreatment. There is a higher risk of this complication with traditional microkeratome LASIK than with bladeless LASIK.
Higher risk complications of LASIK eye surgery include:
Epithelial ingrowth occurs when the tissue from the outer layer of your cornea (epithelium) starts to grow underneath the LASIK flap. This complication presents in 0 to 3.9 percent of LASIK procedures, although the rate goes up in retreatment (touch-up) cases.
Mild cases of epithelial growth do not need treatment. Severe epithelial growth may cause pain, light sensitivity, and blurred vision. These cases require the surgeon to lift the flap and remove the ingrowth.
Corneal ectasia is a rare but visually-devastating LASIK complication resulting in significant corneal thinning. Some studies reported an incidence rate between 0.04 to 0.6 percent of LASIK procedures.
You may need a procedure called collagen cross-linking to strengthen your cornea or corneal implants to improve your vision. One of the biggest risk factors for corneal ectasia is keratoconus. This eye disease causes gradual steepening and thinning of the cornea. If your eye surgeon observes early signs of keratoconus, they usually recommend against laser eye surgery.
Diffuse lamellar keratitis (DLK) is a type of inflammation that occurs under the LASIK flap. This complication typically occurs a few days post-surgery. Mild cases of DLK are self-limiting, and most patients are asymptomatic. Severe cases appear as waves of sand in your cornea, which is why they are nicknamed “Sands of the Sahara.”
Severe DLK is treated with frequent doses of steroid eye drops and may require the surgeon to lift the flap and rinse the inflammatory cells out. Bladeless LASIK has a higher risk of DLK versus traditional LASIK.
Infection requires prompt treatment with antibiotics, and in some cases, the surgeon lifts the flap and applies antibiotic underneath it. Symptoms include pain, redness, and light sensitivity. Overall, infection is rare because the LASIK flap provides protection, and you are prescribed antibiotic eye drops to prevent infection after surgery.
Flap complications include wrinkles and dislocation of the corneal flap created during LASIK. These problems can happen if patients accidentally rub their eyes after receiving LASIK. A flap dislocation or significant flap wrinkles require the surgeon to reposition the LASIK flap.
Most dislocations occur within 24 hours of surgery, but some are seen months to years later, usually due to trauma. A review of 41,845 LASIK patients found a flap dislocation rate of only 0.012 percent.
However, studies comparing only traditional LASIK (not including bladeless LASIK procedures) found a higher flap complication rate of 5 percent. Bladeless LASIK also creates more consistent corneal flaps, which helps with healing.
Overall, the risk of blindness with LASIK is very low. Over 99 percent of people reach 20/40 visual acuity or better, while 90 percent of LASIK patients achieve 20/20 vision or better. Rarely, serious complications can cause significant vision loss. Following post-surgical care instructions and seeing your eye doctor for scheduled follow-up visits are essential to prevent vision-threatening complications.
Although most people obtain good visual acuity post-LASIK, side effects can affect the overall vision and comfort after surgery. The most frequent symptoms include:
Dry eyes after LASIK is one of the most common side effects. Approximately 30 percent of patients experience LASIK-related dry eye. Most dry eye symptoms are mild and resolve within six months of surgery, although a small percentage of people develop chronic dry eye.
However, severe dry eye problems usually occur in people who have dry eyes before LASIK and may be influenced by other factors such as age, hormones, and diet. A traditional LASIK procedure is more likely to cause dry eye versus bladeless LASIK. Artificial tear drops can be used to treat severe cases of dry eye.
Glare, starbursts, or halos are light-related side effects that can affect your night vision. These symptoms are typical during the healing process and subside within a few months or may require an enhancement surgery.
Patients with large pupils are more likely to experience problems. Customized procedures such as wavefront-guided LASIK help minimize these side effects.
Blurry distance or near vision may be related to undercorrection, overcorrection, or regression. The vision can be corrected via an enhancement procedure or an eyeglass prescription.
In rare cases, a patient may lose a couple of lines of vision on a Snellen chart. However, this not going to cause legal blindness.
Monovision LASIK is a procedure to correct near vision for people who need reading glasses. The surgery involves correcting one eye to see distance and the other eye to see up close. Although this option is convenient for patients who do not want to wear glasses, monovision comes with some potential side effects:
Generally, the recovery time across most LASIK procedures (including traditional and bladeless LASIK) is similar.
Here is a general overview of what to expect during your recovery.
The total healing time usually takes about six months. However, if you have a high prescription, your eyes may take a bit longer to heal. Your vision typically stabilizes during this time. If your vision is still blurry, the surgeon can evaluate you for an enhancement procedure or prescribe eyeglasses.
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