LASIK and Vision Surgery
- Corneal Inlays and Onlays
- Corneal Transplant
- Corrective Eye Surgery Basics
- LASIK - Criteria for Success
- Are your eyes healthy? If you have any condition that can affect how your eyes respond to surgery or heal afterwards, wait until that condition is resolved. Examples include chronic dry eyes, conjunctivitis ("pink eye") and any eye injury. Some conditions, such as cataracts, keratoconus and uncontrolled glaucoma, may disqualify you completely.
- Are you an adult? You need to be at least 18 years of age to have LASIK. (Younger patients can sometimes be treated as an exception. Discuss this with your surgeon.)
- Is your vision stable? Many teenagers and young adults experience changes in their prescription for eyeglasses or contact lenses from year to year, especially if they are nearsighted. Make sure your prescription is stable for a 12-month period before having LASIK. If it's not and you proceed anyway, you may need another surgery next year!
- Are you pregnant? Hormonal changes during pregnancy can cause swelling in your corneas, changing your vision. Dry eyes are also common when you're pregnant. Also, eye medications (antibiotics and steroids) used during and after LASIK may be risky for your baby, whether unborn or nursing. Wait a few months after your baby is born before having LASIK.
- Certain systemic and autoimmune diseases may be disqualifiers, too. Examples include rheumatoid arthritis, type 1 diabetes, HIV and AIDS. Basically, if your body has any trouble with healing, your corneas may not heal properly after LASIK. Opinions vary among surgeons as to which diseases are automatic disqualifiers and which ones might pose acceptable risks in certain cases.
- Your prescription must be within certain limits. For example, very high amounts of myopia, which would require removal of too much corneal tissue, may preclude LASIK or make another type of refractive surgery a better option. For example, many surgeons feel a phakic IOL procedure provides a better visual outcome and poses less risk than LASIK for nearsighted prescriptions higher than -9.00 diopters.
- LASIK Risks and Complications
- Surgery for Presbyopia
How to Cope With Low Vision
Low vision is the term used to describe reduced eyesight - either blurred vision (usually 20/70 or worse) or an incomplete field of view - that cannot be fully corrected with eyeglasses, contact lenses or eye surgery. The primary causes of low vision are eye diseases, such as macular degeneration, glaucoma and diabetic retinopathy. But low vision also can be inherited or caused by an eye or brain injury.
A person with low vision is not blind: they have some useful sight. But the degree of their visual impairment can make daily tasks, such as reading and driving, difficult or impossible.
Though children as well as adults can be visually impaired, low vision is mostly a problem that afflicts seniors. Vision loss after a lifetime of good eyesight can be very traumatic, leading to frustration and depression.
Many people who develop eye problems that cause low vision lose their jobs. According to the U.S. Census Bureau's American Community Survey of 2010, the employment rate for visually disabled Americans ages 21-64 (working age) was only 37.2 percent, and the full-time/full-year employment rate was only 24 percent.
Not being able to drive safely, read quickly, or easily see images on a television or computer screen can cause people with low vision to feel shut off from the world. They may be unable to get around town independently, earn a living or even shop for food and other necessities. Some visually impaired people become completely dependent on friends and relatives, while others suffer alone.
Thankfully, in many cases, people with impaired vision can be helped by low vision devices, which include eyeglass-mounted magnifiers, handheld magnifiers and telescopes, and stand-alone magnifiers. There are many ingenious low vision devices and strategies that can help visually impaired individuals get the most out of their remaining sight and, in many cases, continue to live independently.
If you have hazy or blurred vision, light sensitivity, loss of peripheral vision, night blindness, a need for more light than before, unusual floaters or spots, or difficulty reading, your first step is to see an eyecare professional for a complete exam. These could be the first signs of a serious eye disease such as macular degeneration, glaucoma, or retinitis pigmentosa. Or, they could mean you are developing a cataract that needs removal. Whatever the case, it's wise to take action before further vision loss occurs.
If your eye doctor finds you have vision loss that cannot be corrected with eyewear, medical treatment or surgery, you will be referred to a low vision specialist. Usually an optometrist, a low vision specialist can evaluate the degree and type of vision loss you have, prescribe appropriate low vision aids, and help you learn how to use them.
The low vision specialist can also recommend non-optical adaptive devices, such as large-print publications, audio books, special light fixtures and signature guides for signing checks and documents. If necessary, your eye doctor or low vision specialist can also refer you to a counselor to help you cope with your loss of vision.
Article ©2015 Access Media Group LLC. All rights reserved. Reproduction other than for one-time personal use is strictly prohibited.
A corneal transplant - also called keratoplasty (KP), penetrating keratoplasty (PKP), or corneal graft - is the surgical removal of the central portion of the cornea (the normally clear front surface of the eye) followed by replacement with a donor "button" of clear corneal tissue from an eye bank.
Corneal transplants are performed when, because of disease or injury, the cornea becomes scarred or damaged in such a way that it causes vision problems that cannot be corrected with eyeglasses, contact lenses, or refractive surgery such as LASIK.
The National Eye Institute estimates that approximately 40,000 corneal transplants are performed each year in the United States. The success rate for keratoplasty is quite high, but up to 20% of patients may reject their donor corneas. When signs of rejection occur, aggressive medical treatment with steroids can often overcome the reaction and save the cornea. Some studies report keratoplasty success rates of 95% to 99% at five to 10 years after surgery.
Reasons for Corneal Transplants
A common cause for keratoplasty is keratoconus, a degenerative condition in which the cornea becomes thinner and bulges forward in an irregular cone shape. In mild cases, keratoconus can be treated with rigid gas permeable (GP) contact lenses. But in advanced stages of the condition, the contact lenses can no longer be tolerated on the eye. According to the National Keratoconus Foundation, 20% to 25% of patients with keratoconus will require corneal transplant surgery to restore vision.
Other indications for keratoplasty include traumatic injuries to the eye and corneal scarring from infections, chemical burns or other causes. A corneal transplant also may be required in cases of corneal degenerative diseases and corneal ectasia (thinning and bulging of the cornea that is similar to keratoconus) after LASIK or other laser vision correction surgery.
The Corneal Transplant Procedure
Typically, corneal transplants are performed on an outpatient basis, meaning you will not need overnight hospitalization. Local or general anesthesia is used, depending on your health, age and whether you prefer to be asleep during the procedure. The surgeon uses a trephine (an instrument like a cookie cutter) or a laser to cut and remove a round area of damaged or diseased tissue in the center of your cornea, and replaces it with the clear donor tissue.
The donor "button" is attached to your remaining cornea with very fine sutures (less than half the thickness of a human hair). These sutures stay in place for months or even years, until the eye is fully healed and stable.
Recovering from a Corneal Transplant
The total recovery time for a corneal transplant may be up to a year or longer. Initially, your vision will be blurry and the site of your corneal transplant may be swollen and slightly thicker than the rest of your cornea. Eye drops to promote healing and help your body accept the new corneal graft will be needed for several months.
You should keep your eye protected at all times after surgery by wearing a shield or a pair of eyeglasses so that nothing inadvertently bumps your eye. As your vision improves, you will gradually be able to return to your normal daily activities.
Vision After Keratoplasty
Some patients notice improvement in their vision the day following surgery. However, large amounts of astigmatism are common after a corneal transplant. Your vision and eyeglasses prescription will fluctuate for several months after surgery, and vision changes may persist for up to a year.
Gas permeable contact lenses usually provide the best vision correction after keratoplasty, as some irregularity of the corneal surface is common. Glasses with polycarbonate lenses should be worn over the contact lenses for eye protection.
After healing is complete and the sutures are removed, it may be possible to have LASIK or some other laser vision correction procedure to reduce astigmatism and enhance your ability to see without glasses or contact lenses.
Article ©2015 Access Media Group LLC. All rights reserved. Reproduction other than for one-time personal use is strictly prohibited.
Corrective Eye Surgery Basics
Tired of wearing glasses or contact lenses? Today, several surgical methods can correct your eyesight and give you the freedom of seeing well without corrective lenses.
Approaches to corrective eye surgery range from laser reshaping of the eye's surface in procedures such as LASIK and PRK to surgical insertion of artificial lenses to correct eyesight. Here's a brief summary of several refractive surgery options:
PRK (photorefractive keratectomy) was the first laser vision correction procedure approved in the United States, receiving FDA approval in 1995. It soon became a popular alternative to radial keratotomy (RK), which was the only viable surgical treatment for nearsightedness available at the time. PRK promised to reduce or eliminate many of the complications of RK, including fluctuating vision, glare, halos around lights, infection, unpredictable outcomes, decreased visual acuity and regression (return of nearsightedness).
Like LASIK, PRK uses an excimer laser to remove corneal tissue to reshape the eye and correct vision. But with PRK, the laser treatment is applied directly to the surface of the cornea, rather than under a flap of corneal tissue as in LASIK. Visual outcomes after PRK are comparable to those after LASIK. But the eye is uncomfortable for a couple of weeks after PRK, until the thin outer protective layer of the cornea (the epithelium) grows back. Also, vision can be quite blurred for a week or two after PRK until the eye heals.
The number of PRK procedures declined sharply when LASIK was introduced, because there is usually little or no discomfort after LASIK and vision recovers faster. However, PRK has made a comeback in recent years due to more effective pain management techniques and because it poses less risk of certain complications. Recent studies also indicate that PRK and LASIK produce similar outcomes.
LASIK (laser-assisted in situ keratomileusis) is like PRK, except that a thin, hinged flap is made on the cornea prior to the laser treatment. This flap is lifted and folded back, and laser energy is applied to the underlying corneal tissue to reshape the eye. Then the flap is replaced, acting like a natural bandage. LASIK's main advantage over PRK is that there is little or no discomfort immediately after the procedure, and vision is usually clear within hours rather than days.
LASEK (laser-assisted sub-epithelial keratomileusis) is a modification of LASIK in which the corneal flap is thinner, containing only epithelial cells. The delicate epithelium is removed by loosening it from the underlying cornea with an alcohol solution. It's then pushed to the side and the laser treatment is applied. The epithelial "flap" is then replaced and covered with a bandage contact lens until it reattaches to the underlying cornea. In most cases, there is less post-operative discomfort with LASEK compared to PRK, and vision recovery may be faster. LASEK is sometimes preferred over LASIK in cases when the patient's cornea is judged to be too thin for a safe LASIK procedure.
Epi-LASIK is very much like LASEK, except a special cutting tool is used to separate the epithelium from the underlying cornea prior to the laser treatment. This eliminates the possibility of an adverse reaction to alcohol placed on the eye and may quicken the healing process after surgery, compared with LASEK. Like LASEK, epi-LASIK is sometimes preferred over LASIK if there are concerns about corneal thickness.
Bladeless, All-Laser LASIK
Blade-free LASIK involves the use of another laser rather than a mechanical cutting tool to create the flap in LASIK. Sometimes called IntraLASIK, iLASIK or femto LASIK, this procedure eliminates the risk of certain complications that can occur when the flap is created with a microkeratome.
Wavefront LASIK or PRK
Wavefront (or "custom") LASIK or PRK means the laser treatment is determined by a computerized mapping of the power of your eye called wavefront analysis. Wavefront-guided procedures are more precise than ablations determined by using only an eyeglasses prescription, and they can correct subtle optical imperfections called "higher-order aberrations" that regular ablations can't treat. Several studies show wavefront-guided ablations provide sharper vision than conventional (non-wavefront) LASIK or PRK, and may reduce the risk of nighttime glare and halos.
CK (conductive keratoplasty) is a non-laser refractive surgery that uses a hand-held instrument to deliver low-heat radio waves to a number of spots in the peripheral cornea. This causes the corneal tissue to shrink in these areas, which increases the curvature of the cornea, thereby correcting mild amounts of farsightedness or restoring usable near vision to people over 40 who have presbyopia.
CK for presbyopia is called NearVision CK, and it can be used to correct presbyopia for people who previously had LASIK surgery.
Phakic IOLs (intraocular lenses) are small lenses inserted inside the eye to correct vision problems. The lenses can be placed in front of or behind the pupil. "Phakic" refers to the fact that the eye's natural lens remains in the eye during the procedure.
Phakic IOL implantation can correct higher amounts of nearsightedness than LASIK. But because it's an internal eye procedure, there are more risks. Cost of the procedure is also significantly higher.
Refractive Lens Exchange
Refractive lens exchange (or RLE) is another non-laser, internal eye procedure. RLE is much like cataract surgery. But instead of removing the eye's natural lens that has grown cloudy, the surgeon removes a clear natural lens and replaces it with an artificial lens of a different shape, usually to reduce or eliminate high amounts of farsightedness.
RLE has a higher risk of complications and is more expensive than LASIK. Also, removing the natural lens of a young patient will eliminate near focusing ability, which means reading glasses are required. For these reasons, RLE typically is used only in cases of severe vision correction needs.
Yes, even cataract surgery can be considered a refractive procedure. New lens implants can partially restore a person's near vision in addition to correcting nearsightedness and farsightedness. These lenses, called multifocal IOLs or accommodating IOLs, currently are being used by many cataract surgeons, with promising results.
While Medicare and health insurance will cover basic costs of cataract surgery, you can elect to pay out-of-pocket for the extra costs of these more modern lenses that potentially can restore a full range of vision.
Article ©2015 Access Media Group LLC. All rights reserved. Reproduction other than for one-time personal use is strictly prohibited.
LASIK, short for laser-assisted in situ keratomileusis, is the most popular refractive surgery available today. Each year, more than one million LASIK procedures are performed in the United States.
LASIK has become the premier surgery for vision correction because it's quick and painless, there is little or no discomfort after the procedure and vision recovery is rapid - some patients already see 20/20 the following day.
LASIK can correct nearsightedness, farsightedness and astigmatism. With a special technique called monovision, it can also reduce the need for reading glasses among patients over age 40 who wear bifocals.
Am I a Good Candidate for LASIK?
To be a good candidate for LASIK, you should be at least 18 years old, have healthy eyes, and have adequate corneal thickness, since LASIK corrects your vision by removing tissue from your cornea to reshape your eye.
Chronic dry eye problems, corneal diseases and other abnormalities may disqualify you from having LASIK surgery. In order to know for sure if you are a good candidate, a comprehensive eye exam is required. For your convenience, we are happy to provide LASIK pre-operative exams and consultations at our office. Call us for details.
Important considerations when deciding whether to have LASIK are your expectations and your ability to accept a less-than-perfect outcome. LASIK can reduce your dependence on glasses and almost always gives you the ability to function well without the need for glasses or contact lenses. But there are no guarantees, and LASIK doesn't always create perfect vision. In some cases, your vision after LASIK may be permanently less clear than it was with glasses before the procedure. You have to ask yourself if you're willing to accept the risk of such an outcome before you decide to have LASIK surgery.
Remember: LASIK is an elective procedure, not a required one.
The LASIK Procedure
LASIK is an ambulatory procedure. You walk into the surgery center, have the procedure and walk out again. The actual surgery usually takes less than 15 minutes for both eyes, but expect to be at the surgery center for an hour or more.
LASIK is a two-step procedure. In the first step, the surgeon creates a thin, hinged flap of tissue on your cornea with an instrument called a microkeratome or with a laser. This flap is folded back and the second step - the laser reshaping of your eye - begins. After the laser treatment, which usually takes less than a minute, the flap is repositioned and the surgeon moves on to your other eye.
What Is Wavefront LASIK?
Wavefront LASIK (also called wavefront-assisted, wavefront-guided or custom LASIK) means the laser treatment (or "ablation") is determined by a computerized mapping of the power of your eye called wavefront analysis. Wavefront-guided procedures are more precise than ablations determined by using only an eyeglasses prescription, and they can correct subtle optical imperfections of the eye called "higher-order aberrations" that regular ablations can't treat. Several studies show wavefront-guided ablations provide sharper vision than conventional, non-wavefront LASIK and may reduce the risk of nighttime glare and halos.
After LASIK Surgery
After the procedure, your surgeon or an assistant will apply medicated eye drops and clear protective shields over your eyes. You can open your eyes and see well enough to walk without glasses, but you must have someone drive you home.
You will be expected to use medicated eye drops several times a day for a week or so to protect your eyes from infection and help them heal properly. You will also be told to use artificial tears frequently to keep your eyes moist and comfortable.
You should rest and not use your eyes much when you get home from surgery that day. You may also be more comfortable if the lights in your house are dimmed.
The following day, you should be seeing well enough to drive and can resume most activities. Be careful, however, not to rub your eyes until your eye doctor tells you it is safe to do so.
Usually, you will be asked to return to the surgery center the following day so your surgeon or another eye doctor at the center can check your vision and make sure your eyes appear as they should. At this visit, you typically will be given additional instructions about using eye drops and artificial tears, and you will be able to ask the doctor any questions you have.
From this point forward (and sometimes for this "day one" visit as well), your post-operative care may be performed by an eye doctor other than your LASIK surgeon. When your post-operative care is provided by a doctor other than your surgeon or another doctor at the surgery center, it's called co-management. We are happy to provide post-operative care for you at our office through a co-management agreement with your surgeon. Call our office for details.
What If My Vision Is Still Blurry After LASIK?
Though most patients see quite clearly in a matter of days after LASIK, it can take several months before your eyes are completely stable. Until then, improvements in your vision can still occur. But if several months pass and your vision is still blurred, see your LASIK surgeon. Usually a second LASIK surgery (called an enhancement) can sharpen your eyesight further.
If for some reason an enhancement is not indicated or desired, eyeglasses or contact lenses may help. We will be happy to examine your eyes and discuss the different options with you.
Eyewear After LASIK
Keep in mind that, even if your vision seems perfect after LASIK, you still need eyewear.
When outdoors, it's important to protect your eyes from the sun's harmful rays with sunglasses that provide 100% UV protection. If you play sports when wearing sunglasses, make sure the lenses have polycarbonate lenses for extra protection. And anytime you're working with power tools or doing anything else when an eye injury is possible, you should wear safety glasses with polycarbonate lenses.
If you're over 40 (or soon will be), it's likely you'll need reading glasses after LASIK. Also, many LASIK patients can benefit from a pair of prescription eyeglasses for night driving. Though these lenses may have only a mild prescription, they often can make your vision sharper for added safety and comfort.
Eye Care After LASIK
And don't forget to continue to have routine eye exams after LASIK. Even if your vision is perfect, you still need to have your eyes checked for glaucoma and other potential problems on a regular basis. Routine exams also help you make sure your vision stays stable after LASIK.
LASIK - Criteria for Success
Laser eye surgery isn't for everyone. Here are six guidelines to help you decide if LASIK is right for you:
LASIK Risks and Complications
If you are considering LASIK and worry that something could go wrong, you might take comfort in knowing that it's very rare for complications from this procedure to cause permanent, significant vision loss. Also, many complications can be resolved through laser re-treatment.
Selecting the right eye surgeon probably is the single most important step you can take to decrease any risks associated with LASIK. An experienced, reputable surgeon will make sure you are a good candidate for LASIK before a procedure is recommended. And if problems develop during or after the procedure, the surgeon should work closely with you to resolve them.
How Common Are LASIK Complications?
Public confidence in the LASIK procedure has grown in recent years because of a solid success rate involving millions of successful procedures in the United States. With increasingly sophisticated technology used for the procedure, most LASIK outcomes these days are very favorable.
The U.S. military also has adopted the use of refractive surgery, including LASIK, to decrease troops' reliance on prescription eyewear. As of 2008, more than 224,000 military personnel had undergone laser vision correction, with most seeing 20/20 or better after the procedure without corrective eyewear. The rate of complications among military has also been low. In fact, according to one study, only one in 112,500 patients required medical disability retirement due to complications from laser vision correction.
LASIK Complication Rates
Experienced LASIK surgeons report that serious complication rates can be held well below 1 percent if surgical candidates are screened and carefully selected. You may be eliminated as a candidate, for example, if you are pregnant or have certain conditions such as diabetes that may affect how well your eyes heal after LASIK. Discuss any health conditions you have with your eye doctor during your LASIK consultation or pre-operative exam.
Large pupil sizes also might be risk factors for LASIK complications, because pupils in dark conditions could expand beyond the area of the eye that was treated. Again, make sure you discuss any concerns about these or other matters with your eye surgeon.
Other Considerations About LASIK Risks
While the great majority of LASIK outcomes are favorable, there is still that fraction of less than 1 percent of people who experience sometimes serious and ongoing vision problems following LASIK. No surgical procedure is ever risk-free.
Some LASIK patients with excellent vision based on eye chart testing still can have bothersome side effects. For example, it's possible a patient may see 20/20 or better with uncorrected vision after LASIK but still experience glare or halos around lights at night.
When you sign the LASIK consent form prior to surgery, you should do so with a full understanding that, even in the best of circumstances, there is a slight chance something unintended could occur. Even so, most - but not all - problems eventually can be resolved.
Common LASIK Complications
When LASIK complications occur, they are sometimes associated with the hinged flap that's created in the cornea (the clear front covering of the eye) in the first step of the LASIK procedure. This flap is lifted prior to re-shaping the underlying cornea with a laser, and is then replaced to form a natural bandage.
If the LASIK flap is not made correctly, it may fail to adhere correctly to the eye's surface. The flap also might be cut too thinly or thickly. After the flap is placed back on the eye's surface, it might begin to wrinkle. These types of flap complications can lead to an irregularly shaped eye surface.
Studies indicate that flap complications occur in from 0.3 percent to 5.7 percent of LASIK procedures, according to the April 2006 issue of American Journal of Ophthalmology. But inexperienced surgeons definitely contribute to the higher rates of flap complications. Again, remember that you can improve your odds of avoiding LASIK risks by selecting a reputable, experienced eye surgeon.
Some problems associated with LASIK flap complications include:
Irregular astigmatism. Irregular astigmatism can result from a less than smooth corneal surface or from laser correction that is not centered properly on the eye. Resulting symptoms may include double vision or "ghost images." In these cases, the eye may need re-treatment (also called an "enhancement").
Diffuse lamellar keratitis (DLK). Also nicknamed "sands of the Sahara," DLK is inflammation that can occur under the LASIK flap after surgery. In rare cases, DLK leads to corneal scarring. Potentially permanent vision loss can occur without prompt treatment with therapies such as antibiotics and topical steroids. The flap also might need to be lifted and rinsed to remove inflammatory cells and prevent tissue damage.
Ectasia (or keratectasia) is bulging of the cornea that can occur from a flap being cut too deeply, when too much tissue is removed from the cornea during LASIK, or when the cornea was initially weakened as evidenced from corneal topography mapping prior to LASIK. Resulting distorted vision likely cannot be corrected with laser enhancement, and rigid contact lenses or corneal implants (Intacs) may be prescribed to hold the cornea in place.
Other, more commonly reported LASIK complications include:
Dry eye. Almost half of all patients report problems with dry eye in the first six months following LASIK, according to the April 2006 issue of American Journal of Ophthalmology. These complaints appear related to reduced sensitivity of the eye's surface immediately following the procedure. If you have this problem, temporary remedies such as artificial tears or prescription dry eye medication may be needed along with oral flaxseed oil capsules.
After about six months to a year, however, most of these types of complaints disappear when healing of the eye is complete. People who already have severe dry eye usually are eliminated as LASIK candidates.
Significant undercorrection, overcorrection, or regression. An overcorrection or undercorrection of your vision problem means your vision may remain slightly blurred from residual nearsightedness, farsightedness or astigmatism. Regression is when your eyesight is optimal at first after LASIK, but then begins to deteriorate over time (due to a return of some nearsightedness, for example). These problems can usually be corrected with an enhancement LASIK procedure.
Eye infection or irritation. In some rare cases, you may develop an eye infection, inflammation, or irritation that requires treatment with eye drops containing antibiotics or anti-inflammatory medication such as steroids.
Vision Changes Unrelated to LASIK
If you have LASIK in your 20s or 30s, be aware that your reading vision will change as you get older. This has nothing to do with your LASIK surgery - it's caused by a normal age-related loss of focusing ability called presbyopia. Because of presbyopia, most LASIK patients (like anyone else who sees well without glasses in younger years) will need reading glasses after age 40.
Surgery for Presbyopia
Presbyopia is the normal age-related loss of near focusing ability. If you're over 40 and have to move the newspaper farther away to read it, you are beginning to experience presbyopia.
Even if you've had your vision corrected with LASIK surgery in your 20s or 30s, you'll still experience reading vision problems from presbyopia in your 40s, 50s and beyond.
When the time comes, most people deal with presbyopia by wearing reading glasses or eyeglasses with bifocal or progressive ("no-line bifocal") lenses. But if you want greater freedom from glasses after age 40, there are surgical options for the correction of presbyopia as well:
Monovision is a presbyopia-correcting technique where your eye doctor prescribes lens powers for one eye to see clearly across the room (leaving it slightly blurred up close) and the other eye to see well up close (making it slightly blurry far away). The two eyes still work together as a team, but one eye does more of the work for your distance vision, and the other supplies more of your near vision.
Though it may sound odd, monovision contact lens fittings have been done for years, and most presbyopes who try monovision adapt to it quite well. Reading glasses may still be needed for very small print or sustained reading, but a person can usually be glasses-free most of their day with monovision.
Recently, LASIK surgeons have begun using this monovision technique as well, and success rates should be as good as or better than monovision with contact lenses. Before you commit to monovision permanently with LASIK surgery, however, try it with contact lenses first. If it works for you with contacts, you can then proceed with monovision LASIK with greater confidence (provided you meet the other criteria of a good candidate for LASIK).
Monovision CK (NearVision CK)
CK (conductive keratoplasty) uses a hand-held probe to deliver controlled radio-frequency energy to specific spots in the periphery of the cornea. This shrinks the corneal tissue in these spots and steepens the central cornea, making the eye more nearsighted.
NearVision CK, the version of CK for presbyopia, uses a monovision approach and is performed on one eye only. NearVision CK is less invasive and less expensive than LASIK, and is a good option for someone who only needs reading glasses - that is, someone who is presbyopic but has no nearsightedness or astigmatism.
The effects of CK tend to fade over time. So at some point, additional procedures may be needed. As with monovision LASIK, it's a good idea to first try monovision with contact lenses to make sure you're comfortable with it before proceeding with NearVision CK surgery.
Multifocal IOLs and RLE
Multifocal intraocular lenses (IOLs) are a variation of the lens implants that have been used for years in cataract surgery. But instead of having just one lens power to correct nearsightedness or farsightedness, these new lenses have multiple powers to correct vision at all distances.
Multifocal IOLs can be used in cataract surgery to replace the eye's cloudy natural lens, or they can be used to replace a clear natural lens that has just lost its ability to change shape for reading due to presbyopia. This second procedure is called refractive lens exchange (RLE).
Because both cataract surgery and RLE are intraocular procedures, they have more associated risks than less invasive procedures like LASIK and CK. Possible complications of IOL procedures include glaucoma and retinal detachment.
Accommodating IOL (Crystalens®)
Another type of IOL that's used in the same manner as a multifocal IOL is the "accommodating" IOL. This intraocular lens has just one lens power, but the central optical portion of the device is supported by structures called haptics that enable the lens to move slightly forward and backward inside the eye in response to focusing effort. In this manner, an accommodating IOL restores some of the eye's ability to change focus on demand.
The accommodating IOL is approved for use in the United States as part of cataract surgery, and has the same risks as other intraocular lens surgeries.
Multifocal LASIK (PresbyLASIK)
PresbyLASIK is a multifocal variation of LASIK that is available in Europe and Canada, but is not yet FDA approved in the U.S. In PresbyLASIK, the excimer laser creates concentric rings of different powers on the cornea (much like the alternating powers on a multifocal soft contact lens) to provide good vision at all distances.
Studies show presbyopic patients are quite pleased with the overall performance of PresbyLASIK, though many of them still need to wear eyeglasses for some activities. Also, though near vision after PresbyLASIK is usually good in bright light, reading glasses are usually required in low-light situations.
Corneal inlays are another surgical solution for presbyopia. In this procedure, a very small, circular device is implanted within the cornea to improve near vision. The surgery is less invasive than procedures involving larger implantable lenses that are placed deeper in the eye, so it may include fewer risks for many people.