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All About Vision

Cataracts

Cataracts are one of the leading causes of vision loss in people over 60. In fact, by the time we reach 80, more than half of us will have developed a cataract.

A cataract is a clouding of the eye lens which renders vision blurry and unfocused. Having this condition can be compared to looking through a dirty or foggy window.

While the majority of cataracts are a result of the aging process, there are also congenital cataracts that are present at birth, secondary cataracts that result from eye surgery, or diseases such as glaucoma or diabetes, and traumatic cataracts that result at any age from an eye injury.

Though you may be able to live with mild to moderate cataracts, severe cataracts need to be treated with surgery. The procedure involves removing the clouded lens and replacing it with an intraocular lens (IOL).

Cataract surgery is a common procedure that has a very high success rate in restoring vision to patients. Surgery is typically performed on one eye at a time.

Cataracts Signs & Symptoms

Cataracts don’t suddenly develop overnight. They tend to start off small and only noticeably affect your vision as they develop. The first symptom is blurred, hazy, or cloudy vision. You may become sensitive to light, colors may seem dim or faded, and you may notice halos around lights or double vision.

That said, the symptoms people experience may vary. Some individuals report a temporary improvement in near vision when a cataract first develops, a phenomenon known as “second sight”.

Here is a list of cataracts signs and symptoms:

  • Blurry or cloudy vision (that cannot be corrected with contacts or glasses)
  • Glare from lamps, sunlight, oncoming traffic when driving at night, or indoor lighting
  • Colors appearing dim and less vibrant
  • Halos around lights
  • Double vision
  • Poor night vision
  • Sudden improvement in near vision

If you experience any of these symptoms, visit your eye doctor immediately.

What Causes Cataracts?

Cataracts are part of the natural aging process of the eye. However, cataracts can also present at birth or appear following eye injury, surgery, or disease. Environmental, health, and behavioral risk factors can also play a role in cataract development, many of which can be avoided or prevented.

Here are the most common cataract risk factors:

  • Smoking and excessive alcohol consumption
  • Prolonged exposure to ultraviolet (UV) radiation from the sun or other sources
  • Obesity
  • Diabetes
  • Hypertension
  • Certain medications such as steroids or statin medications
  • History of eye injury or eye surgery
  • Family history

Cataract Surgery & Treatment

Cataract surgery is one of the most common surgeries performed in North America and has a 90% success rate (meaning the patient has improved vision, between 20/20 and 20/40 vision, following the procedure).

The surgery involves removing the clouded natural lens and usually replacing it with a clear, plastic intraocular lens (IOL) that becomes a permanent part of the eye. It is a relatively quick and painless procedure and you will not feel or see the IOL after the implant.

That said, being diagnosed with a cataract does not mean that you need to have surgery immediately, or ever. You may be able to live with symptoms of early cataracts for a while by using vision aids such as glasses, anti-glare sunglasses, magnification lenses, strong bifocals, or brighter lighting to suit your needs.

Surgery should be considered only once the condition has begun to seriously impair your vision to the extent that it affects your daily life, such as reading or driving, playing golf, playing cards, or watching TV.

Can Cataracts Be Prevented?

While the development of cataracts is largely associated with age, there are other factors that can increase the risk of developing the condition. Here are steps you can take to delay or prevent the development of cataracts:

  • Protect Your Eyes From the Sun: Ultraviolet radiation can be a factor in the development of cataracts. To protect your eyes from damaging ultraviolet rays, wear 100% UV protective sunglasses and a hat with a brim when under the sun.
  • Stop Smoking and Limit Alcohol Intake: Smoking regularly and consuming large amounts of alcohol have been shown to increase the chances of developing cataracts.
  • Eat Well: Research shows that getting the right nutrition can reduce the risk of age-related cataracts, particularly foods rich with vitamins A (beta-carotene), C and E, and Omega-3s.
  • Get Regular Eye Exams: If you’re over 50, have diabetes, or other eye conditions, it is important to get a comprehensive eye exam every year to check for signs of cataracts and other age-related eye conditions such as age-related macular degeneration or glaucoma. Early detection offers the best chance for successful treatment.

Intraocular Lenses (IOL)

During cataract surgery, the Intraocular lens (IOL) replaces the clouded natural lens. These lenses are typically made of plastic and most of them are monofocal lenses to correct for distance vision. Thanks to technological innovation, specialized IOLs continue to be developed to improve the ease and success of cataract surgery and to improve the patient’s vision. From multifocal lenses to IOLs that block UV and blue light radiation, patients today have greater options available to them.

Presbyopia-Correcting IOLs

The 3 common types of presbyopia-correcting IOLs are multifocal IOLs, accommodating IOLs, and extended depth of focus IOLs.

Multifocal IOLs allow patients to see all distances clearly. The varying optical powers on the lens allow one to see from a variety of distances to be in sharp focus.

It can take some time for people to adapt to multifocal IOL lenses because the focusing power the lenses provide is different from what people are accustomed to. Since the IOL relies on a different design than the bifocal or multifocal optical lenses used in eyeglasses, the brain might need time to adjust.

To ease the adjustment, most cataract surgeons recommend having multifocal IOLs implanted in both eyes, rather than just one.

Accommodative IOLs change focus from distance to near depending on the eye muscle movements.

Extended depth of focus IOLs provide a wider continuous range of high-quality vision, extending the focus from distance into intermediate and even into near range. One of the major advantages is that these lenses provide excellent intermediate vision, ideal for frequent digital device use.

Other Types of IOLs

IOLs that block out ultraviolet (UV) and blue light radiation are also available.

Other premium IOLs exist such as aspheric IOLs which, similar to your real lens, are aspheric in shape and can improve vision quality, especially in low light conditions or toric IOLS which are suitable for correcting astigmatism, nearsightedness, or farsightedness. Premium lenses such as these are more costly than standard monofocal IOLs and may not be right for everyone.

Selecting the right IOL for your eyes, lifestyle and vision is a decision that should be made together with a trusted eye doctor.

If you or a loved one has cataracts and you’d like to learn more or book your appointment, contact American Vision Center - Bloomington today.

 

    Corrective Eye Surgery Basics

    In recent years there have been tremendous advances in the field of vision correcting eye surgery which is also known as refractive or laser surgery. Corrective eye surgery offers patients clear vision without the use of glasses and contact lenses. There are a number of types of refractive surgeries that are able to correct different vision problems, so if you are considering surgery here are some of the options you should know about.

    LASIK

    LASIK (laser-assisted in situ keratomileusis) surgery is perhaps the most well-known refractive surgery today. LASIK can help patients with myopia (nearsightedness), hyperopia (farsightedness) and astigmatism. During the procedure, the doctor makes a flap in the outer layer of the corner to reach the underlying tissue and then uses a laser to reshape the tissue which allows the cornea to then focus light properly. The procedure is usually painless and vision is usually clear within a few hours.

    Recent advances in the field have developed subcategories of LASIK surgery such as Bladeless LASIK, which uses a laser rather than a mechanical tool to make the initial flap or Wavefront (custom) LASIK which uses computer mapping to guide the reshaping of the cornea and is able to create a much more precise visual correction for very subtle optical imperfections. There is also a procedure called Epi-LASIK in which following the procedure, the doctor applies a soft contact lens to protect the surgical area, holding the flap in place while it heals.

    PRK

    PRK (photorefractive keratectomy) also uses a laser to correct mild to moderate myopia, hyperopia and astigmatism. PRK was a precursor to LASIK which eliminated many of the complications of prior surgeries such as glare, seeing halos around lights, blurred vision and regression of vision. Unlike LASIK, the procedure only reshapes the surface of the cornea and not the underlying tissue. Consequently, there is often some discomfort for a couple of weeks until the outer layer of the cornea heals. Additionally, the patient may experience blurred vision during this period of healing. PRK does offer an advantage over LASIK in that there is less risk of certain complications. Wavefront technology is also available for PRK surgeries.

    Due to the increased comfort of LASIK there was a period that PRK saw a decline. Recent studies show however that LASIK and PRK have similar long-term success for improved visual acuity and with the assistance of newly developed effective pain medications, PRK has become more popular again as an option.

    LASEK

    In LASEK or laser-assisted sub-epithelial keratomileusis, the doctor creates a flap smaller but similar but to LASIK, and then uses an alcohol solution to loosen the tissue around the cornea which is pushed aside, and then a laser is used to reshape the cornea itself. In an Epi-LASEK procedure, the doctor may apply a soft contact lens to hold the flap in place to assist in reattaching to the cornea as the eye heals. Patients that undergo LASEK generally experience less discomfort and quicker vision recovery than PRK patients. LASEK may be preferred over LASIK as a safer option for patients with a thin cornea.

    Cataract Surgery

    Cataract Surgery is a very common refractive surgery that removes the clouded natural lens of the eye and replaces it with an artificial lens called an IOL (intraocular lens). Many patients these days will receive a lens that also corrects any refractive error they have such as nearsightedness, farsightedness or presbyopia.

    RLE

    RLE or refractive lens exchange is a non-laser procedure the replaces the natural lens of the eye. This is the same as the surgery that is used to treat cataracts, ,yet for non-cataract patients, RLE is used to correct severe nearsightedness or farsightedness. The procedure involves the doctor making a small cut in the cornea, removing the natural lens and replacing it with usually a silicon or plastic lens. It is particularly useful for patients with minor corneal problems such as thin corneas or dry eyes.

    RLE is more risky than the other procedures mentioned and can affect the patient’s ability to focus on close objects, possibly requiring reading glasses following the procedure. However, in cases of severe vision correction it is often the preferred method.

    PRELEX

    PRELEX or presbyopic lens exchange is for patients with presbyopia, the age-related condition in which you lose the flexibility of your lens and can no longer focus on close objects. Patients that prefer not to wear reading glasses or multifocals, can opt for a procedure in which the doctor removes the natural lens of your eye and replaces it with a multifocal artificial lens. This procedure is often done in conjunction with cataract surgery.

    Phakic Intraocular Lens Implants

    Phakic IOLs are implants that are used for individuals with very high nearsightedness who do not qualify for LASIK or PRK. The implant is attached to your iris or inserted behind your pupil, while the natural lens remains intact. Because this is a procedure that involves the inner eye, it is more risky than LASIK or PRK and is therefore also typically more expensive.

    Conductive Keratoplasty (CK)

    CK uses a hand-held radio wave device to shrink tissue on the cornea to reshape it. The procedure is typically used to treat mild farsightedness and presbyopia, particularly for patients who have already undergone LASIK.

    Any surgical procedure has risks and may have some side effects or complications that you should research before you decide to go ahead with the surgery. Nevertheless, as technology advances these complications are being significantly reduced making refractive surgery a great option for vision correction in many patients.

    LASIK

    LASIK or laser-assisted in situ keratomileusis is a refractive surgery that is used to correct myopia (nearsightedness), hyperopia (farsightedness) and astigmatism as an alternative to eyeglasses or contact lenses. LASIK is currently the most common of the refractive eye surgeries, largely because of the relatively low risk and the quick recovery and improvement in eyesight.

    Also known as laser eye surgery or laser vision correction, LASIK uses a laser to reshape the cornea which is responsible for clear vision. The procedure is quick and relatively painless and eyesight is usually improved to 20/20 vision within one day of the surgery.

    How Does LASIK Work?

    LASIK is an outpatient procedure, which takes about 15 minutes for the actual surgery on both eyes and an hour total with recovery. A topical anesthetic drop is used and there is no need for bandaging or stitches following the procedure. The doctor will start by stabilizing the eye and then making a small flap in the outer layer of the cornea. Then with access to the underlying tissue, he uses a laser to reshape the corneal tissue and re-closes the flap, which will heal on its own. The nature of the corneal reshaping depends on the type of refractive error.

    Wavefront LASIK

    Wavefront LASIK uses computer mapping technology to guide the laser treatment based on the precise shape of the cornea. This can correct very precise issues, provide much sharper vision than non-wavefront LASIK and can reduce complications such as halos, glare and problems seeing at night.

    What to Expect During and After LASIK?

    During the procedure you may feel some pressure on your eye while the laser is working. Immediately following you will likely experience some blurriness and may feel burning or itching (be sure not to rub your eyes!). For your journey home you will be given protective shields to guard your eyes and will need someone to drive you. You will also be prescribed medicated eye drops for a week or so to aid in healing and prevent infection. Your doctor may also recommend artificial tears to moisten the eyes and keep them comfortable in the days following the procedure.

    The day after the surgery you will be asked to visit your eye doctor (or the surgeon) for a checkup and to evaluate whether you are able to drive. Most people experience an improvement in vision by then, although for some it can take a few days or even a week. Your eyes may be sensitive to light for a day or two as well. You will likely be advised to rest for a day or two and to refrain from strenuous physical activity for about a week until further healing has taken place.

    Most people achieve at least 20/20 vision following the surgery, although this can vary and there are cases where 20/40 vision is obtained or where people continue to wear glasses or contacts with a much lesser prescription. Some patients have light sensitivity, particularly when driving at night, also suffering from seeing halos around lights or glare. There are glasses and lenses available to reduce this glare and assist with night driving.

    For some, it can take weeks or even months until the vision completely stabilizes. Occasionally, after a few months, patients who do not experience perfect results will schedule an enhancement or touch up surgery to correct the vision even further.

    Am I a Candidate for LASIK?

    The ideal LASIK candidate is a patient over 18 with generally healthy eyes. Since the procedure involves shaping the cornea by removing some of the tissue, it is not ideal for individuals with a thin cornea or any sort of corneal condition or disease. Patients with chronic dry eyes might also be disqualified as LASIK can often exacerbate these symptoms.

    During a comprehensive eye exam your eye doctor will assess your eligibility by looking at the general health of your eye including your cornea, your pupil, the moisture in your eye, the type of refractive error you have and whether you have any other eye conditions of concern.

    For the right candidate, LASIK can offer a lifestyle improvement in giving clear vision without the need for glasses or contact lenses, however, the results are not guaranteed. You and your eye doctor need to weigh the benefits and the potential risks based on your personal needs.

    LASIK Risks and Complications

    LASIK is the most common refractive eye surgery, partially due to the fact that the risks and complications are low. The majority of patients don’t experience any long term complications as a result of the surgery. Nevertheless, as with any surgical procedure there are some risks, however rare they are and it is important to know them and to discuss them with your eye doctor or surgeon prior to undergoing the surgery.

    Side effects of LASIK

    There are a number of side effects that are somewhat common immediately post-op and in some instances can last longer – sometimes indefinitely. Those include:

    Dry Eyes

    About half of LASIK patients experience dry eyes, which are usually a temporary side effect that resolves within 3-6 months after the surgery. Your doctor will likely prescribe artificial tears in the days and weeks following the surgery which should be continued as long as the symptoms persist. Because of this, it is usually recommended that patients with a history of chronic dry eyes opt for another type of refractive surgery such as PRK, another style of laser refractive surgery with reduced risk.

    Eye Infection or Irritation

    While not common due to the eye drops and checkups prescribed post surgery, there is a chance of developing an eye infection. If this does occur, it can be treated with antibiotic eye drops, anti-inflammatories or sometimes may require other treatment such as oral antibiotics. If you are experiencing symptoms of an eye infection such as redness, pain, discomfort, discharge or any change in vision, see your eye doctor immediately. As a precaution, it is imperative to follow your surgeon’s instructions for your post-operative care including prescription medications and doctor’s visits.

    Vision Issues

    Following surgery, you may experience certain vision issues such as such as poor night vision, double vision, halos around lights or glare. These side effects are common and can last up to a few weeks, but typically go away. Some patients report a lasting reduction in vision in low light conditions and may require vision aids for seeing better at night.

    Other risks of LASIK include surgical errors, many of which can be corrected by a follow-up surgery. These include:

    Overcorrection or Undercorrection

    The key to vision improvement in LASIK is accurate reshaping of the corneal tissue. If too much is removed or not enough is removed, your vision will remain imperfect and when possible may require a follow up procedure to obtain the clear vision being sought.

    Flap Complications

    Perhaps the greatest risk involved in LASIK is the accurate creation and healing of the flap of the cornea that is lifted to reshape the underlying tissue and replaced after. If the flap in the cornea is not made accurately, cut too thick or too thin and not carefully replaced back on the eye, it can cause complications in the shape of the eye surface and therefore clear vision. Studies indicate that these complications occur usually in under 6% of cases and the experience and skill of the surgeon play a large role.

    There can also be complications in the healing process of the flap which include infection or excessive eye tearing.

    Vision Loss

    There is a chance, albeit small that the surgery can result in a loss of vision or reduction in visual clarity due to complications with the surgery.

    It is quite rare for any permanent damage or vision loss to occur as a result of LASIK and usually any vision problems can be corrected by a follow-up procedure. However, as with any surgical procedure, there are risks, so it is important to reduce your risks by finding an experienced surgeon and carefully considering your suitability for the surgery in the first place.

    LASIK – How to Measure Success or Applicability

    Is laser eye surgery for everyone?

    Below are some guidelines to help you decide if LASIK is a good choice for you.

    • Vision stability: Young adults often experience annual changes in their prescription for eyeglasses or contact lenses. A 12-month period of maintaining the same prescription is highly recommended prior to LASIK. Otherwise there is a considerable risk of requiring repeated LASIK surgery in the future.
    • Healthy Eyes: Problems, diseases or conditions related to your eyes could cause increased risks to both the actual surgery and the healing process. If you have a condition that can be treated such as dry eyes, pink eye (conjunctivitis) or any eye injury speak to your doctor. It is probably best to wait until the condition is resolved to schedule your LASIK surgery. Conditions like cataracts, glaucoma, and other more serious conditions may disqualify you from LASIK altogether.
    • Age: 21 is the minimum age of consent for LASIK. Younger patients may be able to get special exemptions based on certain circumstances.
    • Vision prescription range: A very high degree of myopia may require removal of too much corneal tissue. This may exclude your candidacy for LASIK or make another refractive surgery a better option. For example, many surgeons conclude that a phakic IOL procedure provides better results and possesses less risk than LASIK for nearsighted prescriptions higher than -9.00 diopters.
    • Pregnancy: Normal hormonal changes of pregnancy may cause swelling of the cornea which can alter vision. Dry eye is also common during pregnancy. Additionally, medications (antibiotics or steroids) which are administered for LASIK could cause risk to the embryo or nursing infant. It is recommended to delay LASIK for several months after childbirth until the eyes stabilize and risks are reduced.
    • Systemic and autoimmune diseases such as rheumatoid arthritis, type 1 diabetes, HIV or AIDS may disqualify or delay candidacy for LASIK. If your body has trouble healing, your cornea may not heal properly after LASIK surgery. Opinions vary among professionals as far as which diseases automatically disqualify and which ones pose acceptable risks. Discuss this in depth with your doctor if applicable.

    PRK

    Photorefractive Keratectomy or PRK is a type of refractive laser eye surgery used to correct a patient’s vision to eliminate or reduce their dependence on glasses or contact lenses. PRK is the style of laser eye surgery that preceded LASIK, having been the former most common type of refractive surgery until LASIK came along.

    PRK is effective in correcting nearsightedness (myopia), farsightedness (hyperopia) and astigmatism and has very similar rates of success and outcomes as LASIK. PRK remains a common option for laser eye surgery.

    How Does PRK Differ From LASIK

    PRK and LASIK both permanently reshape the cornea to improve vision by using a laser (an excimer laser to be exact) to remove part of the tissue underneath the corneal epithelium. The epithelium first needs to be removed in order to get access to the tissue and how this is done is what differentiates the two procedures. While LASIK creates and lifts a flap on the outer corneal layer, reshapes the corneal tissue underneath and then replaces the flap, PRK removes the outer layer of the cornea completely. The outer layer will regenerate usually within a few days.

    Advantages of PRK

    Since PRK completely removes the outer corneal layer, there is a greater area of the cornea to work with. This is ideal for patients with a thin cornea who would otherwise be at risk with LASIK. It is also usually recommended for patients with chronic dry eyes. With PRK, there is also less risk of infection or issues having to do with the flap and the related healing process. This is an advantage for individuals who lead a lifestyle in which they are at risk for eye injuries (athletes, military, law enforcement etc.) which may subject the flap to injury or complications.

    So, Why Is LASIK More Popular?

    The main advantages that LASIK has over PRK are two-fold and mainly have to do with comfort and recovery time. First of all, PRK patients usually experience slightly more discomfort during the first couple of days of recovery, mainly because it takes time for the outer corneal layer to heal. They will be prescribed eye drops to be taken for several months to prevent infection, increase comfort and assist the healing process. LASIK patients on the other hand, typically experience less discomfort and if they do, it subsides very quickly.

    Additionally, vision recovery takes longer with PRK. While LASIK patients can typically see normally within a few hours after the surgery, with vision gradually continuing to improve within the next few months, PRK patients may experience blurred vision for up to three days and it can take up to six months until they achieve full visual clarity. While patients who undergo LASIK can usually drive and resume normal functioning within a day or two, PRK patients shouldn’t plan on returning to normal for at least several days until the outer layer of the cornea has grown back.

    Whether PRK or LASIK is a better option for you depends on a number of factors, including the health and structure of your eye. This is a decision that your eye doctor or surgeon will help you make. Rest assured however, that both procedures have been shown to be incredibly successful in correcting vision, with minimal complications.

    What You Need to Know About PRK

    Prior to any laser correction surgery, you will meet with a surgeon for a thorough exam to assess your eye health and determine whether you are a candidate and if so, which type of surgery would be best suited to your needs. During this exam it is essential to tell the doctor any relevant medical history (injuries, hospitalizations, diseases etc.) and existing conditions you have. The surgeon will determine if you are currently eligible for surgery and if not, if you will be at a future point, and whether you require any specialized care pre or post surgery.

    The surgery itself is an ambulatory procedure. It takes about 15 minutes or less for both eyes and you go home the same day. You will need someone to drive you home from the procedure.

    The first step in the procedure is that your eye will be anesthetized using numbing eye drops and then a device will be inserted to prop your eyelids open so you won’t blink. Once the eye is numb, the surgeon will remove the outer epithelial layer of the cornea to expose the underlying tissue. Then the surgeon will use the laser to reshape the corneal tissue. You may feel a small amount of pressure during this step. Lastly, the surgeon will apply medicated eye drops and place a temporary contact lens that is used as a bandage to protect the eye.

    Following the surgery you will be instructed to apply medicated eye drops multiple times each day to reduce the risk of infection and you may also be given prescription pain relievers to alleviate any pain or discomfort.

    As with any type of surgery, it is critical to carefully follow your surgeon’s instructions after PRK. Make sure that you take your medication as prescribed, get enough rest, and call your eye doctor immediately if you experience any problems.

    It is normal for it to take several days or even weeks for your vision to improve and up to 3-6 months for full recovery to clear and stable visual acuity. Usually, your doctor will require you to refrain from driving for a week and up to three weeks depending on how fast your vision recovers.

    Risks and Complications of PRK

    While serious complications are rare, like any surgery, there are some risks to PRK, and these happen to be very similar to any laser corrective surgery like LASIK. They include:

    • Dry eyes- this condition usually goes away within a couple of months, but there is a chance that it could become chronic.
    • Infection or Inflammation- the risk of infection is greatly reduced if you take proper care to follow your doctor’s instructions following the procedure.
    • Vision Problems- which can include glare, seeing halos around lights poor night vision and sometimes a general haziness.
    • Incomplete Vision Correction – sometimes an additional procedure might be needed to achieve optimal visual acuity.

    In general, PRK is considered to be a relatively safe and effective treatment for vision correction. If you wish to live a life without depending on your glasses or contact lenses, speak to your eye doctor about whether PRK is an option for you.

    Surgery for Presbyopia

    Presbyopia is a common age-related condition in which near vision worsens due to the hardening of the lens of our eye. It causes people to have difficulty reading and performing other tasks that require sharp and focused close vision.

    Symptoms begin around the age of 40 when you begin to see people with untreated presbyopia holding books, magazines, newspapers, and menus at arm’s length in order to focus properly and avoid eye strain. Other symptoms include headaches or fatigue when trying to focus on something at close range.

    Causes of Presbyopia

    During our youth, the lens of our eye and the muscles that control it are flexible and soft, allowing us to focus on close objects and shift focus from close to distant objects without difficulty. As the eye ages however, both the lens and the muscle fibers begin to harden, making near vision a greater challenge.

    Surgical Treatment for Presbyopia

    The most common form of treatment for presbyopia is wearing reading glasses, bifocals or progressive lenses. Bifocal and multifocals are also available in contact lenses for those who prefer to be glasses-free. A third option, however, is a number of surgical procedures that allow you the freedom of correcting your near vision without the use of glasses or contact lenses.

    LASIK

    Monovision LASIK

    Monovision is a technique that began with presbyopia-correcting contact lenses designed for individuals with presbyopia and nearsightedness or astigmatism. Each eye gets a different lens power – one lens is used in the dominant eye to correct for distance vision and the other for near vision. The eyes adapt to the two lens powers by learning to use the appropriate eye for the necessary distance power. Monovision LASIK surgery is based on the same principle of correcting each eye for a different refractive power and has shown just as high if not higher success rates than the contact lens technique. Usually, patients will try out monovision with contacts first to ensure that it works and that the eyes adapt properly.

    PresbyLASIK

    PresbyLASIK is a procedure that is currently available in Canada and Europe and undergoing clinical trials in the United States. As opposed to monovision LASIK, this procedure is a multifocal alternative in which different rings of refractive power are created on the cornea, similar to multifocal lenses. This provides vision correction at all distances simultaneously.

    Conductive Keratoplasty (CK)

    Conductive Keratoplasty uses radio waves via a hand-held instrument to mold the corneal surface to improve near vision. The procedure can be done on one eye using the monovision principle and is a good solution for those that do not need vision correction for nearsightedness or astigmatism. The effects of CK, however are not permanent and the improvement in near vision will diminish over time.

    Corneal Inlays or Onlays

    Corneal inlays and onlays involve surgically implanting a small lens into the eye to increase focus and near vision. The distinction between inlays and onlays is in where the lens is placed on the eye.

    Refractive Lens Exchange

    In refractive lens exchange the eye’s hardened lens is replaced with an artificial lens called an intraocular lens (IOL) to provide multifocal vision. This surgery is similar to and often done in conjunction with cataract surgery.

    Corneal Inlays and Onlays

    Corneal inlays and onlays are corneal implants that are used to correct presbyopia, a common condition for individuals over age 40 in which the eyes have difficulty focusing on near objects. Presbyopia occurs as the lens of the eye begins to age and weaken, reducing the ability to focus on close objects without the assistance of reading glasses or another visual aid.

    Corneal implants, such as inlays and onlays, offer a treatment solution to correct presbyopia as an alternative to using reading glasses or multifocals to obtain clear vision at a close range. Corneal inlays and onlays are like tiny contact lenses that are inserted into the cornea which reshape it to improve the refractive power and thereby improve near vision. Unlike corrective laser surgery such as PRK or LASIK the actual corneal tissue isn’t touched, but rather the shape of the cornea is changed by the transplanted lens.

    Corneal inlays are placed in the stroma, the middle layer of the cornea (thus the name “in-lays”), while onlays are implanted closer to the surface of the cornea, under the epithelium, which is the thin outer layer of the cornea. The procedures for both inlays and outlays are relatively simple and quick, with minimal recovery.

    Corneal Inlay and Onlay procedures are still in the early stages of development and with a number of clinical trials in progress, the technology should only improve in coming years.

    Corneal Transplants

    The cornea refers to the clear, front surface of your eye. When a corneal transplant is done, officially termed keratoplasty (KP), the central part of the cornea is surgically removed and replaced with a “button” of clear and healthy corneal tissue donated from an eye bank.

    According to the National Eye Institute, approximately 40,000 corneal transplants are performed annually in the United States. The overall success rate for keratoplasty is relatively high, yet up to 20% of patients may reject their donor corneas. Aggressive medical treatment with steroids is generally given in response to signs of rejection, and it is often effective at subduing the negative reaction and saving the cornea. At five to ten years after KP surgery, studies report an encouraging success rate of 95% to 99%.

    Why are corneal transplants done?

    Corneal transplants are typically done when the cornea becomes damaged or scarred in a way that uncorrectable vision problems occur. These types of vision conditions are not resolved by eyeglasses, contact lenses or refractive laser surgery (such as LASIK). Disease or injury is the usual culprit for the vision loss.

    Keratoconus is a common reason for needing a corneal transplant. In this degenerative condition, the cornea thins and bulges forward in an irregular cone shape. Rigid gas permeable (GP) contact lenses can treat mild cases by flattening the cornea, yet contacts are not effective when it comes to advanced stages of keratoconus. The National Keratoconus Foundation reports that 20% to 25% of people with keratoconus will require corneal transplant surgery to restore vision. Other corneal degenerative conditions will also result in a need for keratoplasty.

    Corneal ectasia is a thinning and bulging of the cornea that sometimes occurs after LASIK or other refractive vision correction procedures. In the event that this happens, a corneal transplant may be needed to restore vision.

    Corneal scarring, due to chemical burns, infections and other causes, is an additional reason that a corneal transplant may be indicated. Traumatic injuries to the eye are also commonly responsible.

    Corneal Transplant Procedure

    Keratoplasty is generally done on an outpatient basis, with no need for overnight hospitalization. Depending upon age, health condition and patient preference, local or general anesthesia is used.

    Using a laser or a trephine, this is an instrument similar to a cookie cutter, the surgeon cuts and removes a round section of damaged corneal tissue and then replaces it with the clear donor tissue.

    Extremely fine sutures are used to attach the donor button to the remaining cornea. The sutures remain in place for months (sometimes years) until the eye has recuperated, healed fully and is stable.

    Recovery from a Corneal Transplant

    The total healing time from keratoplasty may last up to a year or longer. At first, vision will be blurred and the site of the corneal transplant may be inflamed. In comparison to the rest of the cornea, the transplanted portion may be slightly thicker. For a few months, eye drops are applied to promote healing and encourage the body to accept the new corneal graft.

    A shield or eyeglasses must be worn constantly after surgery in order to protect the healing eye from any bumps. As vision improves, patients may gradually return to normal daily activities.

    What happens to vision post-keratoplasty?

    Some patients report noticeable improvement as soon as the day after surgery. Yet a great deal of astigmatism is common after a corneal transplant. A patient’s prescription for vision correction tends to fluctuate for a few months after the surgery, and significant vision changes may continue for up to a year.

    Hard, gas permeable contact lenses generally provide the sharpest vision after a corneal transplant. This is due to a residual irregularity of the corneal surface. Even with rigid contact lenses, eyeglasses with polycarbonate lenses must be worn in order to provide adequate protection for the eye.

    Once the sutures are removed and healing is complete, a laser procedure such as LASIK may be possible and advised. Refractive laser surgery can reduce astigmatism and upgrade quality of vision, sometimes to the point that no eyeglasses or contact lenses are needed.

    Controlling Nearsightedness in Children

    Childhood myopia or nearsightedness is a common condition that causes blurred distance vision and can usually be easily corrected with either glasses or contact lenses. Unfortunately, simply getting a pair of glasses doesn’t always solve the problem, because often myopia is progressive which means that every year the vision gets worse. This usually continues until sometime around the child’s 20th birthday when his eyes stop growing and eyesight levels off.

    It can be worrisome and quite disconcerting for both the parent and the child when each visit to the eye doctor results in a higher prescription. There could be a number of factors involved in progressive myopia, involving hereditary factors as well as possible environmental or behavioral factor such as frequent close-up tasks such as reading or using an electronic device. In fact, studies show that children that spend more time outdoors playing have a lower incidence of myopia. Much research is currently being done into treatments for slowing or stopping myopia progression in children. Here are some of the treatment options currently being offered:

    Orthokeratology (Ortho-k)

    Ortho-k is a process that uses specially designed rigid gas permeable contact lenses worn at night to gently reshape the cornea, eventually allowing clear vision during the day. The lenses are worn every night or every couple of nights depending on the results of the individual. Ideal for mild to moderate myopia, ortho-k usually takes a few weeks to show results, during which time the patient may need to temporarily continue wearing glasses or contact lenses.

    Studies show that the use of ortho-k can permanently reduce the progressive lengthening of the cornea which is responsible for nearsightedness and can therefore slow or stop the childhood progression of the condition. Therefore, in addition to being used for myopia correction, it is now also being offered as a therapeutic treatment to halt myopia progression in children.

    Multifocal Eyeglasses or Contact Lenses

    Bifocal or multifocal soft contact lenses or glasses have been shown in some studies to slow myopia progression. This therapy is based on the idea that the eye is strained from accommodating to see close up and that by providing multiple focusing powers, this allows the eye to relax when doing near work, which reduces the progression of the refractive error. This treatment has been shown to delay or slow the advancement of myopia in some children.

    Atropine Drops

    Treatment with atropine drops is another therapy that is used to relax the eye from “focusing fatigue” which may be a culprit in myopia progression. Research is still being done but some studies show that daily use of low doses of atropine drops do slow the progression of myopia. Atropine drops dilate the pupil which temporarily prevents the eye from being able to focus, thereby allowing this mechanism to relax. Research is still being done to determine dosages, but the results are promising.

    If your child has progressive myopia, seek out a pediatric optometrist who is knowledgeable about the options available. Finding the right treatment could give your child the gift of better eyesight for life.