Laser Eye Surgery

Opticians

2007-05-31T04:20:00.002-07:00

Employers usually hire individuals with no eye care educational background as an optician or those who have worked as ophthalmic laboratory technicians. The employers then provide the required training.

Most dispensing opticians receive training on the job or through apprenticeships lasting 2 or more years. Some employers seek people with postsecondary (beyond high school) training in the field. In the 21 States that require dispensing opticians to be licensed, individuals without postsecondary training work from 2 to 4 years as apprentices. Apprenticeship or formal training is offered in most States as well. Formal training in the field is offered in community colleges and a few colleges and universities.

Dispensing opticians may apply to the American Board of Opticianry (ABO) and the National Contact Lens Examiners (NCLE) for certification, which must be renewed every 3 years through continuing education.

Training usually includes instruction in optical mathematics, optical physics, and the use of precision measuring instruments and other machinery and tools.

Under the supervision of an experienced optician, optometrist, or ophthalmologist, apprentices work directly with patients, fitting eyeglasses and contact lenses.

Optometrists

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Optometrists, also known as doctors of optometry, or ODs, provide most primary vision care. Most optometrists complete a four-year bachelor's degree before beginning the four-year program at a college of optometry leading to the doctor of optometry (O.D.) degree. About 10 percent complete an additional resident or post-graduate program in a particular area of interest, according to the American Optometric Association (AOA). Optometrists do not attend a medical school, and they are not medical doctors.

Optometrists examine people’s eyes to diagnose vision problems and eye diseases, and they test patients’ visual acuity, depth and color perception, and ability to focus and coordinate their eyes. Optometrists prescribe eyeglasses and contact lenses and provide vision therapy and low-vision rehabilitation. Optometrists analyze test results and develop a treatment plan. Optometrists often provide preoperative and postoperative care to cataract patients, as well as patients who have had laser vision correction or other eye surgery. They also diagnose conditions due to systemic diseases such as diabetes and high blood pressure, referring patients to other health practitioners as needed. Most optometrists are in general practice, according to the BLS.

Optometrists administer drugs for diagnostic and therapeutic purposes, privileges they have obtained largely through legislative efforts over the past two decades. Some of their professional societies are seeking permission from state regulatory authorities to perform surgical therapies.

Ophthalmologists

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It takes many years of education and training to become a physician: 4 years of undergraduate school, 4 years of medical school, and 3 to 8 years of internship and residency, depending on the specialty selected.

Premedical students must complete undergraduate work in physics, biology, mathematics, English, and inorganic and organic chemistry. Students also take courses in the humanities and the social sciences.

The minimum educational requirement for entry into a medical school is 3 years of college; most applicants, however, have at least a bachelor’s degree. Acceptance to medical school is highly competitive.

Students spend most of the first 2 years of medical school in laboratories and classrooms, taking courses such as anatomy, biochemistry, physiology, pharmacology, psychology, microbiology, pathology, medical ethics, and laws governing medicine.

Ophthalmologists also learn to take medical histories, examine patients, and diagnose illnesses. During their last 2 years, students work with patients under the supervision of experienced physicians in hospitals and clinics, learning acute, chronic, preventive, and rehabilitative care. Through rotations in internal medicine, family practice, obstetrics and gynecology, pediatrics, psychiatry, and surgery, they gain experience in the diagnosis and treatment of illness.

Following medical school, almost all M.D.s enter a residency-graduate medical education in a specialty that takes the form of paid on-the-job training, usually in a hospital.

Physicians are licensed by the states. To be licensed, physicians must graduate from an accredited medical school, pass a licensing examination, and complete 1 to 7 years of graduate medical education. To maintain their license, they must fulfill continuing medical education requirements each year.

M.D.s seeking board certification in a specialty may spend up to 7 years in residency training, depending on the specialty. A final examination immediately after residency or after 1 or 2 years of practice also is necessary for certification by the American Board of Medical Specialists. There are 24 specialty boards, one of which is in ophthalmology. For certification in a subspecialty, physicians usually need another 1 to 2 years of residency. Surgeons are physicians who specialize in the treatment of injury, disease, and deformity through operations. Using a variety of instruments, and with patients under general or local anesthesia, a surgeon corrects physical deformities, repairs tissue after injuries, or performs preventive surgeries on patients with debilitating diseases or disorders.

Although a large number perform general surgery, many surgeons choose to specialize in a specific area, one of which is ophthalmology. Like primary care and other specialist physicians, surgeons also examine patients, perform and interpret diagnostic tests, and counsel patients on preventive health care.

Short glossary

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Astigmatism
A refractive error caused by an irregular shape of the cornea (much like a football). Astigmatism is measured in terms of diopters, cylinder meridian or axis. Uncorrected astigmatism may produce ghosting or double images.

Automated lamellar keratoplasty (ALK)
A procedure in which the surgeon first creates a flap in the uppermost layer of the cornea using a device called a microkeratome. Then the surgeon makes an optical cut after removing additional tissue with a second pass of the microkeratome.

Cornea
The outer part of the eye that provides 70% of the eye's refractive power. The cornea is approximately 500 microns thick (.5 millimeter) and consists of 5 layers epithelium, Bowman's membrane, stroma, Descemet's membrane and endothelium.

Diopters
A measurement of refractive error. Hyperopia is measured in terms of positive diopters. Myopia is measured in terms of negative diopters. The most common refractive errors ranged between +6 to -6 diopters.

Endothelium
The innermost layer of the cornea. The endothelium is one cell layer thick (5-10 microns or .005-.01 millimeters) and provides hydration balance to maintain the cornea's transparency. The endothelium serves three main purposes it regulates the stroma's water content, provides a barrier to ingress of several constituents of the aqueous humor, and actively transports glucose.

Hyperopia
The ophthalmic term for farsightedness. In the hyperopic eye, images are focused in back of the retina. The hyperopic eye is often described as being too flat or too short.

Irregular astigmatism
A refractive error caused by an irregular shape of the cornea in which the curve on one side of the meridian or axis is not symmetrical with the curve on the other side.

Keratectomy
The portion of the LASIK procedure in which the surgeon raises a thin layer of the cornea - creates a corneal flap - with an instrument called a microkeratome, to expose the layer of the cornea called the stroma.

Keratoplasty
The replacement (transplantation) of the cornea. Keratoplasty can be lamellar (replacement of superficial layers) or penetrating (replacement of the full thickness of the cornea).

Laser
An acronym for light amplification by stimulated emission of radiation. A medical instrument that produces a powerful beam of light and can produce intense heat or cool vaporization when focused at close range. Lasers are often used in surgery to remove tissue.

LASIK
The acronym for laser assisted in situ keratomileusis. The name refers the use of a laser to reshape the cornea without invading the adjacent cell layers.

Myopia
The medical term for nearsightedness. Eye is too steep, too long, image is focused in front of the retina.

Presbyopia
The natural deterioration of near vision caused by loss of flexibility in the eye's lens as one ages.

PRK
The acronym for photorefractive keratotomy. A procedure involving the removal of the surface layer of the cornea (epithelium) by gentle scraping and use of a computer-controlled excimer laser to reshape the stroma.

Retina
Light processing membrane; converts light into electrical impulses that are transmitted to the optic nerve.

Quality of life improved with laser eye surgery

2007-05-31T04:05:00.000-07:00

The vast majority of Americans who had their vision corrected by laser surgery are highly satisfied with the results and said that the overall quality of their lives and daily routines has improved, according to the results of a Harris Interactive survey released by The Eye Surgery Education Council (ESEC), the public education arm of the American Society of Cataract and Refractive Surgery (ASCRS).

The survey is the first nationwide quality of life survey assessing life implications for laser eye surgery patients. The survey asked patients to evaluate the impact of their eye surgery on the quality of their family life, careers, and sports. These survey findings, along with the ESEC’s newly updated LASIK screening guidelines, can help interested patients make educated choices by weighing the benefits and risks of laser eye surgery.Of the approximately 3 million Americans who underwent laser eye surgery since 1995, more than 85 percent said the surgery improved their overall quality of life and 93 percent of patients said they were satisfied with the results.

Among the benefits of the procedure, respondents cited improvement in several specific aspects of vision, daily living and everyday activities, including:
Ability to see upon waking (seeing an alarm clock) (89%)
Freedom from glasses and contacts (83%)
Improvement in personal safety (69%)
Increased confidence in personal appearance (65%)
Better participation in sports or fitness activities (54%)

Specific to the surgery, 87 percent felt that the results met or exceeded their expectations and 73 percent of patients regretted that they did not have the surgery sooner. In addition to the high satisfaction rate, nearly half (47 percent) of the respondents said they began “a whole new life” after laser eye surgery.

Intraocular lenses

2007-05-31T03:55:00.000-07:00

Surgically implanted lenses, also called phakic IOLs (intraocular lenses), are a new option for people seeking more permanent correction of common vision errors such as myopia. These implants, which resemble contact lenses, are placed between the clear front covering of the eye and the (colored portion of the eye) or just behind the iris.

Implantable lenses are a surgical alternative to LASIK. Both procedures alter the way light rays enter the eye to achieve sharper focus. LASIK does this by removing tissue from the eye's cornea to change its shape; implantable lenses function like glasses or contact lenses, except they do it from within your eye. Implantable lenses do not require tissue to be removed from the eye as with LASIK; these lenses are effectively added to the eye.

Implantable lenses are similar to the intraocular lenses (IOLs) used in cataract surgery. However, implantable lenses are placed in eyes that retain their natural lens, unlike in cataract surgery where IOLs replace a natural lens that has turned cloudy.

Eye surgeons may consider implantable lenses for their patients when other vision correction procedures aren't a good option, such as in cases of thin corneas or myopia between -3.00 diopters and -20.00. With some patients receiving phakic IOLs, LASIK may be used as a follow-up to refine vision correction.

Insertion of the Verisyse phakic IOL.

Two Food and Drug Administration-approved implantable lenses now are available in the United States, including:

Verisyse (Advanced Medical Optics, Santa Ana, Calif. Marketed as the Artisan outside the U.S. by Ophtec, Groningen, The Netherlands) In September 2004, one phakic IOL known as the Verisyse received FDA approval for correcting nearsightedness in moderate to severe ranges of -5 to -20 diopters; patients must be 21 years or older. Made of a type of plastic known as PMMA, this lens has been marketed for a number of years in Europe under the trade name Artisan.

Visian ICL (Staar Surgical, Monrovia, Calif.) A second lens, the Visian ICL or Implantable Collamer Lens, received final FDA approval for marketing in the U.S. in late December 2005. The Visian ICL is made partly from a biocompatible material known as collagen. The ICL is foldable, which means smaller surgical entry incisions and potentially reduced recovery times. FDA approval is for patients older than 21 with nearsightedness in moderate to severe ranges of -3 to -20 diopters. Many years before FDA approval, the Visian ICL was approved and marketed in many countries outside the United States, including in Europe.

The Visian ICL (Implantable Collamer Lens).
Both the Verisyse and ICL implantable lenses are FDA-approved for treating nearsightedness only. Clinical trials for the two lenses are continuing for potential FDA approval for treating near vision defects. A version of the Visian ICL also is being studied for correction of higher levels of astigmatism.

How the Procedure Is Done

Prior to surgery, drops are placed in the eye to reduce pupil size. An instrument is attached to hold open the eyelids during the procedure, and a local anesthetic is given to numb the eye's surface. An incision then is made into the eye. The Verisyse phakic IOL is inserted and attached to the colored portion of the eye (iris). Tiny, dissolvable stitches are used to close the wound. An eye shield will need to be worn for a short time following the procedure, which lasts about 15-30 minutes.

The folded Visian ICL is inserted just behind the eye's iris and in front of the natural lens. After being placed through the microincision, the artificial lens then unfolds to its full width following implantation, which requires no sutures. Once inserted during about a six-minute procedure, the Visian ICL is invisible to the naked eye because of its location behind the iris. It can only be seen with a microscope during eye examinations.

What to Expect Immediately After Lens Implantation

After the procedure, vision often is instantly improved, though there may be a feeling of mild scratchiness. Patients should rest at home the remainder of the day and then return the next day for an eye examination in the office. Most patients are able to resume driving and return to work within a day. A series of routine, follow-up visits with the eye doctor also are required.
After the lenses are inserted, patients cannot feel them (unlike traditional contact lenses). Because these lenses are designed to be permanently added to the eye, they have the added advantage of never requiring removal for cleaning, as occurs with traditional contact lenses.

Expected Outcomes

In one study preceding FDA approval of the Verisyse lens, about 92% of 662 myopic patients who received an implant achieved 20/40 or better eyesight. FDA studies demonstrated that about 95% of 294 myopic patients receiving the Visian ICL implant achieved 20/40 or better vision, which enables driving without glasses if no other vision defects are present. Reversibility appears to be one of the procedure's main advantages over laser vision correction such as LASIK. The implant simply can be removed if the eye changes, complications occur, or the phakic IOL correction no longer is effective.

Risks of Lens Implantation

As with any surgical procedure, complications are rare but can occur following implantation of phakic IOLs such as increased chance of retinal deatachment, loss of cells in the thin layer covering the cornea, inflammation, infection, and cataracts. The FDA warns of other potential complications such as sometimes severe vision loss, problems with night driving that can include halos, increased eye pressure that can damage the eye's optic nerve, and inadequate lens power that may not properly correct vision.

PRK

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It may be hard to believe these days, when everything is "LASIK this" and "LASIK that," but PRK (photorefractive keratectomy) used to be the most common refractive srurgery procedure. Both are grouped under the umbrella "laser eye surgery," but each is a little different when it comes to advantages and disadvantages. LASIK patients have less discomfort and obtain good vision more quickly (with PRK improvement is gradual and over a few days or even months), but many surgeons prefer PRK for patients with larger pupils or thin corneas.

PRK was invented in the early '80s. The first FDA approval of a laser for PRK was in 1995, but the procedure was practiced in other countries for years. In fact, many Americans had the surgery done in Canada before it was available in the U.S.

PRK is performed with an excimer laser, which uses a cool ultraviolet light beam to precisely remove ("ablate") very tiny bits of tissue from the surface of the cornea in order to reshape it. When you reshape the cornea in the right way, it works better to focus light into the eye and onto the retina, providing clearer vision than before.

Both nearsighted and farsighted people can benefit from PRK. With nearsighted people, the goal is to flatten the too-steep cornea; with farsighted people, a steeper cornea is desired. Also, excimer lasers can correct astigmatism, by smoothing an irregular cornea into a more normal shape.

Before Surgery
If you are considering PRK, your first step is to choose a surgeon. Your doctor will examine your eyes to determine exactly what kind of vision correction you need and how much laser ablation is needed. A corneal topographer will be used; this is an instrument that photographs your eye and creates a kind of "map" of your cornea. No one has a perfectly rounded cornea, and the topographer will display the corneal irregularities and the actual steepness or flatness that the surgeon must address.

During Surgery
PRK is an ambulatory procedure; you walk into the surgery center, have PRK, and walk out again. In fact, the actual surgery usually takes less than a minute, and you're awake the whole time. Occasionally, the doctor will give a mild oral sedative beforehand.
Most people don't feel pain during PRK. Your eyes are first anesthetized with special drops. The doctor will have you lie down, then make sure your eye is positioned directly under the laser. (One eye is operated on at a time.) A kind of retainer is placed over your eye to keep your eyelids open — normally, this is not uncomfortable. It has a suction ring that keeps your eye pressurized and immobile.

LASEK eye surgery

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LASEK (laser epithelial keratomileusis) is a relatively new procedure that is technically a variation of PRK. Also called epithelial LASIK or E-LASIK, LASEK is used mostly for people with corneas that are too thin or too flat for LASIK. It was developed to reduce the chance of complications that occur when the flap created during LASIK is not the ideal thickness or diameter.

The LASEK Procedure

In LASEK, the epithelium, or outer layer of the cornea, is cut not with the microkeratome cutting tool used in LASIK, but with a finer blade called a trephine. Then the surgeon covers the eye with an alcohol solution (perhaps one part alcohol and four parts sterile water) for around 30 seconds. The solution loosens the edges of the epithelium.

After sponging the alcohol solution from the eye, the surgeon uses a tiny hoe to lift the edge of the epithelial flap and gently fold it back out of the way. Then he or she uses an excimer laser, as in LASIK or PRK, to sculpt the corneal tissue underneath. Afterward, the epithelial flap is placed back on the eye with a kind of spatula.

After LASEK

In many ways, what you can expect from LASEK is similar to what you can expect from LASIK, but there are some differences. According to doctors who perform LASEK, the flap edge heals in about a day, though patients usually wear a bandage contact lens for around four days. You may feel eye irritation during the first day or two afterward. Also, the time it takes to recover good vision is often longer — up to four to seven days. Of course, it varies from one person to the next.

If you are considering LASIK, but your doctor says you need LASEK instead, ask why. It's not for everyone, but many surgeons who perform LASEK consider it a better option for some patients who will probably not do very well with LASIK. Also, LASEK in some studies has been associated with faster recovery of sensation or nerve function in the eye's surface (cornea) compared with LASIK.

Epi-LASIK

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Epi-LASIK is a new laser eye surgery procedure that was developed to solve some of the potential problems with LASIK and LASEK. It's kind of a cross between the two, but differs in a few key areas.

LASIK involves cutting a flap in the cornea with either a sharp blade or a laser; with LASIK also comes the risk of cutting the flap too thickly. LASEK involves cutting the cornea's outer layer, the epithelium, in a thin sheet that retains its hinge on the eye. This is done in Epi-LASIK too, but the surgeon uses a blunt, plastic oscillating blade instead of LASEK's finer blade. Also, instead of the alcohol that's used in LASEK to loosen the epithelial sheet, in Epi-LASIK the surgeon uses the plastic blade, called an epithelial separator, to separate the sheet from the eye. This avoids the possibility of a reaction from the alcohol, which can kill epithelial cells.

Because it is more difficult to create the epithelial flap in people with steeper corneas (who have higher amounts of myopia), the procedure is more appropriate for people with less steep corneas (who have low myopia).

After the epithelial flap is made, it is lifted and gently folded out of the way. An excimer laser is used, as in LASIK or PRK, to sculpt the underlying corneal tissue. Then the epithelial flap is placed back on the eye with a kind of spatula. A special contact lens is placed on the eye to keep the flap in place while it re-epithelializes. Surgeons use a high-Dk contact lens for this, which means it is very oxygen-permeable. The contact lens protects the surface of the eye and allows the epithelial cells to grow back properly.

If you have Epi-LASIK you'll likely experience some pain, which is manageable with over-the-counter painkillers. The pain is reportedly less than with PRK or LASEK.

After Epi-LASIK

By about the third day after surgery re-epithelialization has occurred, so the doctor may permit you to remove the contact lenses. Vision will probably not be perfect immediately: in three days many patients do have 20/40 or even 20/20 vision, but others take longer — possibly three or six months — to reach their final result. Usually people can drive in about a week after surgery.

These recovery times are significantly longer than with LASIK, which usually allows people to achieve good vision from the same day up to a few weeks later and to drive by the day afterward.

As with any laser eye surgery, after Epi-LASIK it is very important to follow your surgeon's instructions exactly, because the quality of the final vision you achieve is affected by how well your corneas heal. Don't neglect to use the eye drops or other medications you are prescribed, and don't miss any follow-up appointments.

Who Can Have Epi-LASIK

If you are considering LASIK, but your doctor says you need Epi-LASIK instead, ask why. It's not for everyone, but many surgeons who perform Epi-LASIK consider it a better option for some patients who will probably not do very well with LASIK. These include people who have thin corneas, with not enough tissue for a good LASIK flap. And those who have professions or hobbies that increase the chance of being hit in the eye (such as soldiers, police officers, boxers, and racquet sports enthusiasts) may find Epi-LASIK safer than LASIK because there's no risk of the flap being dislodged.

If you have Epi-LASIK, you will likely experience some discomfort after the procedure. This is usually manageable with over-the-counter painkillers. The discomfort after Epi-LASIK is reportedly less than that experienced after PRK or LASEK.

Which LASIK Laser Is Best?

2007-05-31T03:39:00.000-07:00

Excimer lasers, manufactured to perform laser-assisted in situ keratomileusis (LASIK), are, one and all, marvels of modern medicine. Many potential LASIK recipients, though, are interested in the subtle differences among the currently approved instruments.

But for most people, the choice of laser makes no significant difference. Most experts agree that surgeon skill and experience and the quality of care before and after LASIK are far more critical factors affecting final vision outcomes. Although all approved lasers meet safety and effectiveness criteria established by the U.S. FDA, certain patients may be better off with one type of laser over another.

When comparing lasers, the informed consumer naturally is drawn to the data gathered during FDA clinical trials. A number of important points can help keep the FDA data in perspective: Today's results are probably better than FDA data. By definition, FDA trials occur during the early period of a laser's life cycle. Manufacturers are allowed to and often do make technical improvements to the instruments, sometimes even while the lasers are still under investigation. This, together with increasing surgeon experience over time, means that results in actual clinical practice are often better than the initial FDA data.

FDA data in one study cannot fairly be compared to FDA data in another study. Manufacturers go to the FDA with various study designs, which often have differing endpoints and patient-enrollment criteria. Although all studies must answer certain basic questions regarding safety and effectiveness, they are not designed to be compared with one another. A true comparison of Laser A and Laser B would require randomized clinical trials (RCTs), in which patients would be randomly assigned to receive surgery by one laser or the other over the same time period by the same surgeons. FDA trials don't do that, although other studies sometimes do.

Studies don't cover every possibility. Just because you have a characteristic or condition that is not covered by the approved labeling of a laser doesn't mean that the laser won't work for people with your characteristic or condition. Neither does it mean that another laser approved to treat people with your characteristic will do a better job. Remember, these studies have differing designs, and people with your characteristic or condition may or may not have been included, or their results may or may not have been analyzed, or there may have been too few such people in the studies to determine statistical or clinical significance.

Once the FDA approves a laser, your surgeon can use it any way he or she deems appropriate. This is true of all FDA-approved drugs and devices. This is commonly referred to as "off-label" use of an FDA-approved drug, device, or laser. It's called a physician's practice-of-medicine prerogative, and there's nothing inherently wrong with it. In medicine, doctors often use one technology for a patient with a condition that was not in the FDA clinical trial. The use of that equipment in this regard is called "off-label," while characteristics included in the FDA study are "on-label." A common example of off-label use is a doctor recommending aspirin to reduce the risk of stroke, although aspirin originally was FDA approved for pain relief.

Eye surgery

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Also known as ophthalmic surgery or ocular surgery, is surgery performed on the eye or its adnea, typically by an ophthalmologist. Although most eye surgery can be performed by an experienced general ophthalmologist, more complex procedures are usually done by one who is fellowship trained.

LASIK prices

2007-05-31T03:27:00.000-07:00

After rising for several years, seemed to stabilize in 2006. Industry sources report that the average LASIK price in the second and third quarters of 2006 was about $1,950.

For comparison, in 2002 it was $1,550-$1,600; by October 2003 it had risen to $1,710; at the end of 2004, it was a little over $1,800; and in 2005 it was $1,965. These averages take into account procedures performed at surgeon-owned laser centers, institutions, and corporate laser centers.

A leading multi-center LASIK provider, TLC Laser Eye Centers, reported average fees per procedure in 2002 as $1,800. In the fourth quarter of 2004, TLC's average price was $1,957. In 2005 and into 2006, it's been around $2,000.

LASIK procedure

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LASIK is the most commonly performed refractive surgery procedure - actually short for "laser-assisted in situ keratomileusis."

LASIK has advantages over other procedures, including a relative lack of pain afterward and the fact that good vision is usually achieved by the very next day. An instrument called a microkeratome is used to create a thin, circular flap in the cornea.

The surgeon folds the flap back out of the way, then removes some corneal tissue underneath using an excimer laser. The excimer laser uses a cool ultraviolet light beam to precisely remove ("ablate") very tiny bits of tissue from the cornea to reshape it. When the cornea is reshaped in the right way, it works better to focus light into the eye and onto the retina, providing clearer vision than before. The flap is then laid back in place, covering the area where the corneal tissue was removed.

Both nearsighted and farsighted people can benefit from the LASIK procedure. With nearsighted people, the goal is to flatten the too-steep cornea; with farsighted people, a steeper cornea is desired. While this is not widely recognized by consumers, excimer lasers also can correct astigmatism by smoothing an irregular cornea into a more normal shape.

Refrctive errors

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Refractive errors are caused by an imperfectly shaped eyeball, cornea or lens, and are of three basic types:

myopia — nearsightedness; only nearby objects are clear.

hyperopia — farsightedness; only objects far away are clear.

astigmatism — images are blurred at a distance and near.

There's also presbyopia — "aging eye." The condition usually occurs between ages 40 and 50, and can be corrected with bifocals or reading glasses.

The facts

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Lasik is surgery to a very delicate part of the eye.

Hundreds of thousands of people have had Lasik, most very successfully.

As with any surgery, there are risks and possible complications.

Lasik may not give you perfect vision. The American Academy of Ophthalmology (AAO) reports that seven out of 10 patients achieve 20/20 vision, but 20/20 does not always mean perfect vision.

If you have Lasik to correct your distance vision, you'll still need reading glasses around age 45.
Lasik surgery is too new to know if there are any long-term ill effects beyond five years after surgery.

Lasik surgery cannot be reversed.

Most insurance does not cover the surgery.

You may need additional surgery — called "enhancements" — to get the best possible vision after Lasik.

Common Laser Procedures

2007-05-30T14:26:00.000-07:00

The two types of Excimer laser surgery performed commonly in Canada are PRK (Photo-Refractive Keractectomy), first introduced in the early nineties, and LASIK (Laser Assisted in situ Keratomileusis), introduced in the mid-nineties. There are also more recent procedures called LASEK (Laser Epithelial Keratomileusis) and Epi-LASIK.

PRK: The surgeon removes the outer layer of the cornea (epithelium) with a surgical blade or blunt instrument. The laser beam, guided by a computer, is then used to vaporize tiny amounts of tissue under the surface of the cornea. The procedure removes just enough tissue to reshape the cornea in a way that corrects vision. The initial healing process is complete in about a week.

LASIK: This surgery is more complicated. The surgeon first cuts a flap in the cornea with a very sharp blade or laser, and then lifts it and uses a computer-guided laser to remove calculated amounts of tissue from the inside layers of the cornea. Afterwards, the flap is put back and the eye heals more quickly than with PRK.

A recent advance in LASIK surgery is the use of Wavefront technology, which creates a detailed map of the eye. This helps the surgeon make even more precise correction to vision. Your eye surgeon can advise whether this is an option for you.

LASEK: This is a variation of PRK and LASIK. The surgeon cuts the outer layer of the cornea (epithelium) with a fine blade, and uses alcohol to loosen and lift it in a single layer. The laser beam is then directed at tissue under the epithelium, as with PRK. When the laser procedure is finished, the epithelium is put back in place. LASEK is best suited to vision problems that require minor correction. The healing process takes about two weeks.

Epi-LASIK: This is a modified LASEK in which the outer layer of the cornea is removed with a mechanical device using a blunt, rather than a sharp blade.

Benefits and Risks of Laser Eye Surgery

Laser eye surgery is performed by highly trained specialists, and in most cases, the results are satisfactory. Some patients feel their lives are vastly improved when their dependence on prescription glasses or contact lenses is reduced or eliminated. However, laser eye surgery also poses certain risks.

With PRK, the risks include: pain, ranging from moderate to severe, for the first few days;
hazy vision during the healing process, which usually clears up within the first week after surgery; and
regression, which in some cases can cause the eye to regress to its previous refractive error within about six months. If this happens, the patient may need a second operation (called an “enhancement”) or may need to start wearing glasses or contacts again.

With LASIK, there is less post-operative pain. However, since this procedure involves cutting into the cornea, there is a greater risk of complications, including the following:
dry eyes, which can range from mild to significant and can affect vision;
poor quality of night vision due to halos and glare, which could affect your ability to drive at night; and
a serious condition called corneal ectasia, which is a weakening and bulging of the cornea. Severe cases may need to be treated with a corneal transplant or implant.

A serious complication that may occur with both PRK and LASIK is corneal infection (infectious keratitis), which may result in significant loss of vision.

The more recent LASEK surgery shares some of the problems associated with both PRK (pain, haze and regression) and LASIK. However, the LASEK procedure reduces the risk of some of the complications associated with cutting a flap in the cornea, such as weakening of the eye and dry eyes.

The risks of laser eye surgery go up significantly for people with certain conditions or lifestyles. When weighing the risks, you should have a detailed talk with the surgeon about the following:
your medical condition (including family history) - especially regarding such conditions as lupus, diabetes and keloid formation, as well as any eye diseases (e.g., herpes simplex, glaucoma, dry eyes, eyelid infections or previous eye surgery);

whether or not you play sports where you are likely to be hit in the face - after LASIK, there is a risk for years that the flap could dislocate; and

your career plans - some occupations (e.g., police officer, pilot) have specific vision requirements that can be achieved with laser eye surgery. Still, it is a good idea to discuss your plans for surgery with current or future employers, as well as your surgeon, to make sure your plans do not affect your prospects for employment.

Correct vision problems

2007-05-30T14:21:00.001-07:00

Laser eye surgery is the most commonly practiced procedure to correct vision problems caused by refractive errors, including myopia (near-sightedness), hyperopia (far-sightedness) and astigmatism (distorted vision when looking at objects at any distance).

More recently, laser eye surgery has also been used to correct presbyopia (the inability to focus on nearby objects), which is part of normal aging and can be corrected by using reading glasses.
All of these conditions are caused by problems with the way the eye focuses an image on the retina, which is the light-sensitive layer at the back of the eye. A large part of the eye's ability to focus depends on the shape of the cornea, the clear front surface of the eye.

During laser eye surgery, a surgeon uses a laser device to make permanent changes to the shape of the cornea. The laser used most often is the Excimer laser, which produces a beam of ultraviolet light to vaporize tissue. Surgically altering the shape of the cornea can correct mild to moderate refractive errors in most people.

Eyes

2007-05-30T14:11:00.000-07:00

Eyes are organs of vision that detect light. Different kinds of light-sensitive organs are found in a variety of organisms. The simplest eyes do nothing but detect whether the surroundings are light or dark, while more complex eyes can distinguish shapes and colors.