Modern LASIK eye surgery delivers excellent visual outcomes at an extremely high success rate. Of course, making sure you are a suitable candidate for LASIK is an essential part of a successful procedure.
Studies show that 99 percent of LASIK patients reach 20/40 vision, while 90 percent of patients achieve 20/20 vision.
Here are some general guidelines to determine if you are the right LASIK candidate. This list does not substitute a consultation with the eye surgeon but helps you understand some of the criteria the doctor checks for when evaluating your eyes.
Your overall eye health determines how well your eyes heal after surgery and whether or not you are at risk for certain complications. In general, any active eye infections, inflammation, or abrasions must be resolved before you get LASIK. If you have severe dry eye syndrome, LASIK can aggravate your symptoms. Working with your eye doctor to improve your dry eyes before surgery is crucial.
If you have a corneal disease such as keratoconus or corneal dystrophy, you are most likely not a good candidate for LASIK. Tell your surgeon if you have a history of herpes-related eye infections since LASIK can reactivate the herpes virus.
LASIK can also affect your eye pressure. If you have glaucoma or are at risk for glaucoma, your eye doctor can determine whether or not LASIK surgery is safe for you.
Before LASIK, your eye doctor dilates your eyes to examine your retina. If you are highly myopic (nearsighted), your retina tends to be thinner, and you may be at higher risk for retinal detachments. Although the overall risk of a retinal detachment after LASIK is low, the eye surgeon may recommend against LASIK if you have a history of retinal tears or other retinal conditions.
LASIK procedures can treat a wide range of prescriptions, including myopia (nearsightedness), hyperopia (farsightedness), and astigmatism. The treatment range varies between different types of LASIK procedures. Your eye surgeon can help you determine which type of LASIK is right for you.
If your prescription is too high, the surgeon may recommend an alternative procedure. A refractive lens exchange and phakic intraocular lens implant are two procedures that can correct higher prescriptions. They both involve the insertion of an artificial lens implant into your eyes.
The higher your prescription, the more corneal tissue the laser must remove to correct your vision. During LASIK, the surgeon cuts a flap on your cornea, then uses a laser to remove tissue underneath the flap. If your corneas are thin, LASIK can increase your chances of corneal ectasia, which is a vision-threatening condition that causes abnormal corneal thinning.
Modern LASIK techniques, such as bladeless LASIK, may require less corneal tissue. Photorefractive keratectomy (PRK), another type of laser eye surgery, is an alternative if you are not eligible for LASIK. Refractive lens exchanges and phakic intraocular lens implants are also potential options.
Typically, you must be at least 18 years old to have LASIK. However, it is best to wait until you are in your mid-20s, which is when your vision stabilizes for the most part.
There is no upper age limit for receiving LASIK, although there are some important considerations. After age 40, presbyopia begins to set in. This process affects your ability to focus up close and continues until about age 60.
LASIK does not correct your near vision unless you opt for monovision LASIK. Otherwise, most patients who receive LASIK need reading glasses once they are over 40.
Older age also increases your risk for dry eyes and other eye conditions that may affect your eligibility for LASIK.
If you have stable vision for at least 1-2 years before LASIK, this reduces your chances of regression and needing a touch-up procedure. Stable vision does not necessarily mean your prescription cannot change at all. In most cases, a change of 0.25 or 0.5 Diopters is acceptable. Diopters are the units used to measure your prescription.
Besides age, other factors that may cause your vision to fluctuate include hormones, diabetes, and certain medications.
If you are thinking about LASIK, getting a yearly eye exam is ideal. This way, your eye doctor can track vision changes from year to year.
Common post-LASIK symptoms include glare, halos, and starbursts at night. Previously, eye doctors linked these symptoms to pupils that were larger than the LASIK treatment zone, particularly in dim light. However, many studies show that with modern LASIK procedures and wider treatment zones, large pupils do not significantly affect visual outcomes.
The eye surgeon takes your pupil measurements into account when determining your LASIK treatment plan. Another thing to keep in mind is that your pupils are larger when you are young and get smaller over time.
Before having LASIK, you should consider the potential side effects and complications. If your job requires you to have precise vision, you may want to reconsider laser eye surgery in the event you experience any side effects.
Although LASIK success rates are very high, it may not be realistic to expect perfect vision. Even the surgeon cannot predict with complete certainty how your eyes will heal after surgery since everyone is different. Also, keep in mind the possibility of needing glasses after surgery, such as for reading or night driving.
Not everyone is a good candidate for LASIK. Some criteria can exclude you from getting LASIK altogether, while other criteria indicate you may be at higher risk for complications. Your eye surgeon can determine if any of your health conditions are contraindications for LASIK.
These are some conditions that may prevent you from getting LASIK:
Many women experience fluctuations in their vision during pregnancy related to hormonal changes. Also, the medications you may take for the LASIK procedure are not safe for the baby. It is best to wait until you have your baby and are finished nursing.
People with certain autoimmune or immunodeficiency diseases are at higher risk for healing complications and generally should not receive LASIK. Collagen vascular disorders, which are a group of autoimmune diseases, include rheumatoid arthritis, lupus, and Sjögren's syndrome. People with these conditions tend to have significant dry eye problems and are at risk for a complication called corneal melting.
Diabetic patients may experience delayed wound healing after LASIK and may experience visual fluctuations related to blood sugar changes. However, it may be possible to have LASIK if your diabetes is well-controlled, and you do not have any eye problems due to diabetes.
Age-related cataracts usually start to develop around age 60 and cause the lens inside your eye to become cloudy. Generally, LASIK is not recommended if you already have cataracts. LASIK cannot correct your vision entirely, and your vision will continue to change as the cataracts progress.
Most eye surgeons recommend waiting until you need cataract surgery. This procedure not only gets rid of your cataract but corrects your vision as well. The surgeon places an artificial implant in your eye that restores your eyesight.
If you engage in high-impact sports such as basketball or martial arts, consider your options carefully. Although this complication is rare, eye trauma can potentially dislodge the corneal flap, even long after your surgery.
When you consult an eye surgeon, make sure to discuss any activities that may put your eyes at risk. Your eye surgeon may recommend PRK instead of LASIK since the surgery does not involve creating a corneal flap.
Certain drugs are not safe to use if you are having a LASIK procedure. Immunosuppressants and anti-inflammatories can affect the healing process. Some medications that should not be taken before LASIK include steroids, isotretinoin (Accutane), and amiodarone. Your eye surgeon can advise you how long you need to discontinue the medications before surgery.
If you had an eye injury that left a significant corneal scar, you might not qualify for LASIK. Previous eye injury or eye surgery may increase your risk for LASIK complications, so be sure to give the eye surgeon your complete health history. If you already had laser eye surgery in the past, it might be possible to have a second enhancement procedure.
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