By Dr. Neil F. Martin
Special thanks to Gazette
Laser vision correction is the most technologically advanced method available today for treating the common visual problems or farsightedness, nearsightedness and astigmatism. During the last decade, millions of these procedures have been performed in more than 50 countries.
LASIK is an advanced form of laser vision correction that allows for the correction of most degrees of farsightedness (hyperopia), nearsightedness (myopia) and astigmatism. It has largely replaced photorefractive keratectomy (PRK) as the procedure of choice for laser vision correction.
In LASIK (laser in-situ keratomileusis) the surgeon creates a thin, hinged flap in the cornea with an automated surgical instrument called a keratome. A predetermined micro-thin layer of tissue from the exposed corneal surface is then shaped with a cold, invisible beam of laser energy. The flap is replaced and self-adheres by natural suction without the need for sutures or bandages.
LASIK is an improvement over the decade-old PRK. PRK is performed by removing the epithelium surface cells of the cornea and lasering the exposed surface. The epithelium regenerates itself in several days to a week.
LASIK and PRK are completely different from radial keratotomy (RK). RK, a largely abandoned procedure, requires deep freehand surgical corneal incisions that give limited and less predictable vision correction of nearsightedness. LASIK relies on computerized automated instrumentation to achieve more reproducible results.
LASIK is painless and can be performed in outpatient facilities, using eye drops for anesthesia. The procedure takes seven to 10 minutes per eye.
While the flap is being created, the patient is aware of pressure and dimmed vision for less than a minute. The patient then focuses on a target light. The invisible beam of light energy from the excimer laser is guided by the ophthalmologist surgeon. The flap is repositioned and it self-adheres.
Patients can see immediately after the procedure, but vision may be misty for a few hours. Although the eyes are usually gritty for a few hours, pain is unusual. Most patients can drive to the doctor for their checkup visit the next day without glasses and return to work on subsequent days.
LASIK results depend on the patient's degree of nearsightedness or farsightedness. Uncorrected 20/20 vision can be achieved in more than 80 percent of cases and driving vision of 20/40 is achieved in 95 percent of patients. If necessary, the results can be improved by lifting the flap and relasering at a later date.
Short-term postoperative effects may include light sensitivity, poor contrast in dim illumination and periods of blurred or hazy vision. Complications of flap healing such as infection or corneal clouding require another corrective procedure. No cases of blindness have been reported from the procedure. Long term results are difficult to predict.
LASIK has provided permanent correction for most degrees of nearsightedness and astigmatism for years and is now available for farsightedness. As with any medical or surgical procedure, a patient should consult an eye doctor for a careful individual evaluation and detailed discussion of the benefits and risks of LASIK as a means of vision correction.
Aging eyes may benefit from laser correction
By Dr. Neil F. Martin
Special thanks to the Gazette
Q: Can lasers correct presbyopia?
A: Hyperopia is often confused with presbyopia. Presbyopia is a condition that occurs as a normal part of the aging process. The lens in the eye begins to lose flexibility, making it difficult to read. This typically occurs between the ages of 40 and 50, requiring the use of reading glasses or bifocals. The laser has no effect on the lens or the focusing muscle attached to the lens. Patients with hyperopia often develop presbyopia early and greatly benefit from hyperopic laser vision correction. In general, patients who wear bifocals prior to the procedure will only need reading glasses (non-bifocals) after the procedure.
Many patients choose to have"monovision" which allows for good distance vision in one and reading vision in the other, further reducing the need for reading glasses.
Q: Does the procedure hurt?
A: The procedure is painless and usually takes about 10 minutes. There are no needles and anesthetic drops are used to numb the eye at the time of surgery. After surgery most patients experience irritation for a few hours. Dryness in the eyes can last up to a few days. Very rarely will a patient experience pain. Most patients are able to resume activities within a few days.
Q: Is LASIK covered by insurance?
A: Most insurance companies do not cover LASIK, but you are encouraged to check with your provider. Although LASIK may be deemed elective and not covered, it may be tax deductible or covered in a cafeteria or defined benefit plan.
Q: Who is a good candidate for hyperopic LASIK?
A: A good candidate is someone who has been dependent upon glasses or contact lenses for distance and near. He wants to decrease dependency on glasses or contact lenses and is willing to accept the possibility that corrective lenses may be necessary occasionally. Although not all patients achieve 20/20 uncorrected vision, the vast majority of patients can drive without glasses. A good candidate for LASIK accepts good but not necessarily perfect vision without glasses. He understands that some vision could be lost postoperatively. The patient also understands that the need for near vision correction is a normal part of aging and that although the amount of lens power required for reading may be reduced, reading glasses likely will be needed sometime between the ages of 40 to 50. Many LASIK candidates are contact lens intolerant or have contact lens problems. Some may consider LASIK for employment eligibility requirements. Some people desire LASIK to enhance their participation in sports or other vigorous activities. A poor candidate is a patient who demands perfect vision without correction forever, who expects LASIK to cure other life-related problems or who is unable to evaluate the benefits, risks and alternatives of a surgical laser procedure.