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Advancements in ophthalmology have made it safer than ever before to undergo laser vision correction. The technology used in LASIK (laser-assisted in situ keratomileusis) surgery has continued to evolve steadily since the advent of the procedure, making it more reliable and effective over the years. In fact, the American Academy of Ophthalmology (AAO) states more than 90 percent of LASIK patients achieve between 20/20 and 20/40 vision. Advanced software, three-dimensional corneal mapping technology, and the use of lasers instead of blades have reduced the risks associated with LASIK eye surgery.
If you are ready to reduce or eliminate your need for glasses and contact lenses, it is important that you become fully acquainted with the criteria for candidacy, the procedural steps, and the technology used during the surgery. It is equally important that you understand the risks associated with LASIK, as well as the measures that both you and your ophthalmologist can take to minimize these risks.
Leading ophthalmologists spend considerable time explaining the many advanced safety measures taken during LASIK surgery. If the patient feels apprehensive even after gaining a full understanding of these safety protocols, some doctors offer the option of undergoing the procedure while under intravenous (IV) sedation. This will help the patient to feel calm and relaxed during surgery.
LASIK: The Basics
In order to grasp how technology has made LASIK the safe and effective treatment it is today, it is important to understand the fundamental principles of LASIK. Irregularities in the shape of the cornea, the dome-shaped surface of the eye, can result in nearsightedness or farsightedness, with or without astigmatism. Glasses and contact lenses have specific contours, or correction, that compensate for these irregularities, helping the patient to see more clearly.
LASIK is a procedure in which an excimer laser is used to correct corneal irregularities, which in turn reduces or eliminates the need for corrective eye wear. Every patient's corneal surface is as unique as a fingerprint, and today, wavefront technology is used to create a three-dimensional digital map of the cornea to identify even the smallest irregularities and guide treatment. This method is more sophisticated than traditional methods of determining the extent of treatment needed.
During surgery, a hinged flap is created in the epithelium (outer layer) and superficial stroma (outermost portion of the inner layer) of the cornea, granting access to the inner portion of the stroma. Traditionally, a blade has been used to create the flap. However, many modern practices now offer all-laser LASIK, in which a femtosecond laser is used to create the flap. Once the flap has been created, the excimer laser makes the necessary refinements to the cornea. Finally, the corneal flap is replaced.
Advanced Precautionary Tools
Innovations such as iris registration and automatic centering reduce the risk of inaccuracies during LASIK to a minimum. Iris registration is a process of designating reference points on the iris, the colored ring surrounding the pupil that distinguishes an eye as being blue, brown, green, or other colors. Using advanced technology, an ophthalmologist can digitally “mark” points on the cornea. Some practices use the VISX Star S4™ laser, which actively tracks the position of these points 4,000 times per second using ActiveTrak automatic centering, and will not discharge or continue to discharge the laser if these points move.
In the old days, before automatic tracking, it was much more common to be a little off-center with the correction. Today, iris registration and automatic centering make LASIK treatment accurate and safe.
Thorough Screening: A Crucial Step in Minimizing LASIK Risks
One of the surest ways a surgeon can prevent LASIK complications is to make certain that the patient is a suitable candidate for the procedure. In fact, New York State Ophthalmological Society President Gary S. Hirshfield, M.D., F.A.C.S. says the initial consultation can play the most significant role in reducing the risks of LASIK.
The greatest risk lies in inadequate pre-operative evaluation and informed consent
"The greatest risk lies in inadequate pre-operative evaluation and informed consent," he said. "The surgeon must rule out conditions like dry eye syndrome in order to accomplish proper patient selection, and must educate the patient in what can be accomplished, and what the risks are."
You should expect your surgeon to conduct a meticulous review of your medical history, as well as an in-depth eye examination. Patients may not be candidates for LASIK if they have been diagnosed with conditions including:
- Glaucoma: Excessive pressure can build within the eye when fluid cannot properly drain. This condition is called glaucoma, and it can cause damage to the optic nerve and retina, potentially resulting in blindness. Intraocular pressure (IOP) increases during LASIK surgery, and this could increase the risk of damage to the retina and optic nerve if a patient is already experiencing high IOP. Many patients with controlled glaucoma can safely undergo LASIK, but others cannot.
- Keratoconus: Those suffering with keratoconus experience a change in the shape of the cornea from the normal dome-like shape to a protruding cone-like shape. The inherent instability of a cornea affected by keratoconus precludes a patient from undergoing LASIK.
- Other Corneal Diseases: Conditions such as Fuch's Endothelial Dystrophy, which involves the deterioration of the inner surface of the cornea, also cause corneal instability. If you have been diagnosed with this or other corneal diseases, you may not be a good candidate for LASIK.
Reducing LASIK Risks by Choosing an Outstanding Ophthalmologist
While ophthalmologists carry the ultimate responsibility of delivering safe LASIK treatment, patients themselves can take many measures to reduce the risk of complications. Patients should take time to research different practices in their area, and choose a surgeon who uses advanced technology and has a reputation for providing excellent results.
When it comes to some products and services, choosing a bargain makes a lot of sense. Laser vision correction is not one of those services.
When it comes to some products and services, choosing a bargain makes a lot of sense. Laser vision correction, especially custom LASIK, is not one of those services. Be discriminating when it comes to the surgeons you consider, and choose the best surgeon based on their experience, track record, and technology, not on the price of their work.
Side-effects during LASIK Recovery
All surgery requires a recovery period, and the same holds true for LASIK. For the first month or so following surgery, it is common for vision to fluctuate to some degree. Your eyes may feel a bit irritated immediately following surgery, but this usually subsides quickly. Your eyes may also feel a little dry, but this should not be confused with dry eye syndrome.
Your ophthalmologist should schedule follow-up appointments to monitor your recovery and make certain that you are not experiencing any complications. Some doctors provide patients with antibiotics to reduce the risk of infection, and steroids to reduce the risk of inflammation. Certain activities, such as swimming, should be avoided for about two weeks or so.
While some dryness, irritation, and fluctuation in vision can be expected, it is important to understand that sophisticated innovations in LASIK surgery have made the risk of complications like dry eye syndrome, glare and halos, and infection low when the procedure is performed by a skilled surgeon using advanced technology.
Dry Eye: A Rare Side-effect
Dry eye is something rarely seen anymore, mostly because advanced technology allows doctors to take a minimally invasive approach to creating the corneal flap. Using a laser instead of a blade leaves more of the cornea intact, allowing the eye to maintain its natural reactions to dryness. Basically, instead of a flap taking up 95 percent of a cornea, a flap created with a laser takes up only about 50 percent.
Dry eye occurs when the tears are unable to keep the eye adequately moist. This can happen either because the composition of the tears (water, oil, and mucus) is out of proportion, or because the lacrimal glands fail to produce enough tears.
With older tools and techniques, LASIK always involved large, inconsistent flaps, and this made dry eye a much bigger risk. There are nerve endings on the surface of the cornea, including the fifth cranial nerve. Studies have indicated that when a large flap is created, this crucial nerve can be severed. As a result, the eye can no longer tell when it is dry, and cannot act accordingly. By using lasers to create the corneal flap, doctors disrupt as little tissue as possible, preserving the ability to produce tears as needed.
Halos, Glare, and Night Vision
The advent of intralase has also lowered the risk of LASIK patients developing higher order aberrations. Lower order aberrations refer to the corneal imperfections that cause nearsightedness, farsightedness, and astigmatism. Higher order aberrations, on the other hand, are tiny imperfections in the cornea that can result in halos (bright rings surrounding street lamps and other light sources at night), glare (compromised vision in the presence of bright light, such as car headlights or direct sunlight), and compromised night vision. Everyone experiences higher order aberrations to some degree, but they can be quite pronounced in some individuals.
In the past, when blades where the only available method of creating the corneal flap, LASIK patients ran a greater risk of developing higher order aberrations. The blades created meniscus flaps, which were thinner in the center than on the outer edges, which would often induce higher order aberrations. Laser technology allows us to not only create less invasive flaps, but also to create flaps that do not induce higher order aberrations.
Infection and Inflammation
The AAO reports that infection rates are extremely low in LASIK patients, and can easily be cleared up with medications.
Everybody heals differently. Some patients can be more inflamed than others following surgery. Therefore, it is important to undergo follow-up appointments with your laser eye surgeon. Medications may have to be adjusted, and other measures may be recommended, but an experienced and reputable surgeon can help you through any inflammation you experience so you can heal comfortably and begin enjoying the full benefits of laser eye surgery as soon as possible.
According to the AAO, studies indicate that less than one percent of all patients who undergo all-laser LASIK surgery develop an ingrowth of epithelial cells between the corneal flap and the stroma. The condition can lead to compromised vision, glare and halos, and other symptoms. The AAO reports that epithelial ingrowth occurs in only about one percent of LASIK procedures performed with a blade, but again, research indicates that patients wishing to minimize their risks should choose a surgeon who provides intralase.
Over-correction and Under-correction
When some people hear about over-correction or under-correction, they assume a procedure has failed, but in reality, this just means the patient is one of a small percentage who needs a touch-up.
Everyone responds differently to LASIK. These rates can be compared to a bell curve. Ninety-six percent of LASIK patients will respond the same way, while two percent of patients have corneas that respond more to the laser than others, resulting in over-correction. The remaining two percent of patients have corneas that are less responsive, resulting in under-correction. This is why many practices have some kind of commitment on enhancements. Some surgeons offer a lifetime commitment of touch-up procedures at no charge. When choosing an ophthalmologist to perform your procedure, you should ask if the doctor has this policy.
LASIK Recovery: Reducing Risks by Following Pre- and Post-operative Instructions
Patients can further reduce the risks of LASIK by adhering to their ophthalmologist's instructions during recovery. Leading up to surgery and afterward, patients can help ensure a successful outcome by following simple steps.
When it comes to LASIK, these steps include taking medication and using eye protection as directed, avoiding rubbing the eyes, ceasing use of lotion and makeup, and avoiding sunlight. It is usually recommended that patients stay home from school or work for at least two days, and make sure to attend scheduled follow-up appointments. The U.S. Food and Drug Administration recommends that patients avoid strenuous contact sports, such as football or boxing, for at least four weeks to protect the eyes from getting bumped.
Case Study: Helping Anthony Live and Work Free of Glasses and Contacts
Technology goes a long way in providing safety - and peace of mind - for many patients.
[My doctor] and I spent a long time talking about the procedure. He was really on point about letting me know about the risks up front, and about how the technology he uses reduces those risks
Anthony, an operations manager at a local fitness center, is a patient who recently underwent LASIK surgery. He spends most of his work day on his feet, and was eager to be able to go about taking care of work orders and other tasks without having to deal with glasses. He had been wearing corrective eye wear since the second grade, and was also looking for a way to stop spending money on glasses and contact lenses.
Anthony said when he attended his initial consultation, he had little apprehension about the risks of the procedure.
“I had known about LASIK for a long time, and my mother had also had it done,” Anthony said. “[My doctor] and I spent a long time talking about the procedure. He was really on point about letting me know about the risks up front, and about how the technology he uses reduces those risks. The fact that the procedure is bladeless made me feel a lot more confident.”
After surgery, Anthony reported experiencing minimal side effects.
“There was no dry eye, no halos,” he said. “At first, my vision was a little hazy, and there was a little irritation that first night as I was trying to sleep, but the next day, I was fine. Anyone considering LASIK should know that when your doctor is using the best technology, it’s painless and very quick. When something that has been limiting you for so long can be changed instantly, it’s life-changing.”
Safe Refractive Surgery Is within Your Reach
LASIK has helped many to enjoy a greater quality of life, free from the restrictions of corrective eye wear. No surgery is entirely free of risk, but you can take simple steps to ensure that your treatment is safe and effective. Spend time talking to anyone you know who has undergone LASIK, and do your homework online to identify excellent ophthalmologists using advanced technology in your area. With ample preparation, you can expect to undergo a safe and beneficial procedure.
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