New optical surgery seamlessly corrects vision

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    By Jessica Gleason

    Seen through the microscope just minutes after Jim Kasen’s eye surgery, the line of the incision on his left cornea is barely perceptible as he blinks.

    What little visible evidence there is of his surgery will be gone by morning, according to Dr. Randall Ellsworth, who performs, on average, three of these procedures every week.

    Though the incision won’t be healed until morning, the result of Kasen’s Lasik surgery is immediate. Although his vision will be watery for a few hours, he can see without the aid of glasses or contact lenses.

    Like nearly 70 million Americans, Kasen is nearsighted, but unlike most of those people, he will now see 20/20 when he wakes up every morning. Lasik surgery, less commonly known as laser in-situ keratomileusis, is the young offspring of two older procedures – Lamellar keratoplasty (LK), and photo-refractive keratectomy (PKR).

    From LK, Lasik takes the microkeratome. Sloped like a plywood skateboard jump, the microkeratome lifts a microscopic flap of cornea from the eye as it slides gently across the surface.

    While this hinged piece of cornea is lifted from Jim’s eye, the excimer laser originated with PKR vaporizes a disk of the inner cornea.

    The result, for naturally myopic (or nearsighted) people like Kasen, is a flatter cornea, and a much greater likelihood that the eye’s point of focus will be directly on the retina, instead of falling short.

    This surgery can also correct astigmatic corneas, which are not spherical, as most, but shaped more like a football. The different coordinates of these misshapen corneas result in two points of focus in the eye. A person with astigmatism sees a blurry outline around everything to varying degrees, depending on the severity of the condition.

    Lasik can correct astigmatism by part of the laser ray being disrupted with disks that allow the laser to penetrate deeper in some areas than in others, resulting in a rounded cornea.

    What sounds like a miracle to people who suffer from myopia and astigmatism may be an elusive one because of its price. The cost for Lasik surgery is around $4,000 for both eyes. This includes a facility fee to rent the equipment and a surgeon’s fee which, in Ellsworth’s case, includes pre-operative education and a year of post-operative check-ups.

    Most insurance companies consider this 20-minute surgery elective and don’t cover it, although some employee benefit programs allow refractive surgery to be paid for with pre-tax income.

    Kasen, a social worker at the dialysis center at Utah Valley Regional Medical Center, thought the surgery was worth the cost. Just before going into the operating room, however, he jokes about being nervous for his surgery, noting that there is no red and white cane dispenser in the waiting room.

    David Day, a friend of Kasen, had Lasik surgery in September 1997 and was at Kasen’s surgery to drive him home. The only sign of Kasen’s nervousness in the operating room was his shallow breathing while the microkeratome made its incision, and Day had to point that out.

    According to Day, the pressure of the microkeratome on the eye is the most worrisome part of the seven-to-10-minute procedure on each eye.

    When the microkeratome passes, Ellsworth has already marked the cornea with radial lines.

    “I made marks on the flap,” he tells Kasen, “so when it’s down, I’m sure it will line right up.”

    Once the lines are made and the microkeratome has made its pass over the cornea, the doctor begins to conversationally direct his patient and his nurse, Shannon Orozco, to prepare for the laser.

    “Do you see the green light now?” Ellsworth asks Kasen.

    “Here we go,” to the nurse, “50 percent.”

    Again to Kasen, “Find the green light now.”

    “75 percent.”

    The steady ticking sounds like a plastic card in the spokes of a bicycle as Orozco begins the laser again.

    “Find the green light; we’re almost done. This is where it’s easy to get a little lazy. Concentration.”

    After Kasen has kept his eye trained on the green light for 100 percent, there is the almost-imagined odor of singed flesh in the room, even though the excimer laser is non-thermal to insure that no damage is done to the surrounding optical tissue.

    “You look wonderful, James…close your eye…now open…open…and close.”

    After the flap has been replaced and properly aligned with a sponge-tipped swab, and Kasen has blinked away the antibiotic wash, Ellsworth explains each step of the procedure, pointing out that with Lasik, there is virtually no post-operative pain, because there are no nerve endings exposed to the air.

    According to Mary Fridell, the refractive coordinator at Central Utah Eye Associates, PC, where Ellsworth practices, the protective flap created by the microkeratome not only reduces post-operative pain, but decreases the risk of infection.

    It is Fridell’s job to educate prospective Lasik recipients of all possible effects of the surgery. Other advantages of Lasik over other refractive surgeries include: less risk of scarring, less corneal haze, more rapid visual recovery and a capability to treat a wide range of myopia.

    The surgery isn’t risk-free, and not everyone will recover to Kasen’s 20/20 vision, but according to Ellsworth, 90 percent of patients have at least 20/40 vision after their Lasik surgeries. That means that at 20 feet, they are able to see what a person without any vision problems – “normal” people – can see at 40 feet, and that is good enough to pass the drivers’ test in most states.

    Lasik for nearsightedness and astigmatism has been approved in the United States, and Fridell says the Food and Drug Administration is expected to approve a Lasik procedure to correct hyperopia – or farsightedness – within the next 6 to twelve months.

    A reversal of the procedure used for myopia, the laser eliminates an outer portion of the cornea in hyperopic patients, causing the inner part of the cornea to protrude and make the eye longer and the focusing point fall on the retina instead of beyond the back of the eye.

    Already, some clinics such as Vista Alliance Eye Care Associates in New York are able to offer FDA clinical trials to farsighted patients, and Lasik is being used to correct hyperopia in Mexico and Canada.

    Not everyone with vision problems is eligible for Lasik surgery, however. A candidate’s optical prescription must have become stable, which usually occurs after the age of 21. Women who are nursing or pregnant are not eligible for Lasik, because the cornea changes because of these conditions.

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