LASIK

Refractive Errors of the Eye

Laser vision correction surgeries are designed to correct refractive errors of the eye, including nearsightedness (myopia), farsightedness (hyperopia), presbyopia, and astigmatism. These refractive errors appear when light entering the eye is focused improperly by the cornea and crystalline lens before being projected onto the retina.

Myopia, or nearsightedness, is a condition that occurs when the eye is longer or has a steeper cornea than a normal eye. For myopic individuals, close objects can be seen clearly, while objects at greater distance appear blurry.

Hyperopia, or farsightedness, occurs when the eye is shorter or has a flatter cornea than a normal eye. For hyperopic individuals, far-away objects are seen more clearly than objects close by.

Astigmatism describes a condition in which the eye is irregularly curved, which causes light rays to be focused inconsistently depending on their angle of origin with respect to the eye. Astigmatism may be to blame for blurry vision, headaches, eye pain, fatigue, and double vision.

Presbyopia describes the natural degradation of vision with age. It typically manifests around age 45, when the crystalline lens begins losing its focusing ability. Individuals experiencing presbyopia have to hold reading material further away or must rely on reading glasses. Conductive Keratoplasty® is an FDA approved procedure to correct presbyopia.

Laser vision correction involves reshaping the cornea to improve visual acuity using a high-energy laser known as the excimer laser. With the aid of this computer-controlled laser, Dr. Julie Lee is able to remove tissue from the cornea with extreme precision. The two laser eye surgeries performed most frequently by Dr. Julie Lee are laser in-situ keratomileusis (LASIK) and photorefractive keratectomy (PRK).

LASIK involves removing tissue from the middle layers of the cornea using the excimer laser. LASIK can be used to treat myopia, presbyopia, and astigmatism. There are two steps to the LASIK procedure. First, a corneal flap is created, which is lifted to expose the inner cornea for step two, tissue ablation by an excimer laser. Once the cornea has been reshaped, the flap is repositioned, at which point the procedure is complete. LASIK is popular because it is extremely effective, with very low incidence of complications. LASIK patients generally recover very quickly, with little discomfort reported following the procedure.

PRK differs from LASIK in that it uses the excimer laser to reshape the front surface of the cornea, rather than the interior layers. Part of the epithelium, a layer of cells on the outer surface of the cornea, is removed to expose the corneal tissue itself. Once the cornea has been reshaped, the procedure is complete. Because it takes several days for the epithelium to heal, PRK patients will have to wear a soft contact lens to protect the cornea. Dr. Julie Lee often recommends PRK to patients who are not good candidates for LASIK. PRK patients generally take longer to recover, and are required to use steroid eye drops for some time after the procedure to facilitate proper healing of the cornea.

New developments in laser vision correction technology have made LASIK even safer, more accurate, and more effective than ever before. These technologies are known as the IntraLase Method™, or “bladeless LASIK,” and CustomVue™, or “custom LASIK.” Both of these technologies have revolutionized laser vision correction by making completely customized procedures a reality.

he IntraLase® FS laser introduced the concept of blade-free LASIK in 2001, representing the first improvement in the procedure’s first step – creation of the corneal flap. In the IntraLase Method™, a laser is used to create the corneal flap during LASIK, rather than the conventional microkeratome blade. Rapid, precise laser pulses applied to the cornea cause bubbles to form beneath the surface. Once the bubbles have formed, Dr. Julie Lee will separate the affected tissue to create the corneal flap.

This technique allows the dimensions of the flap to be set precisely according to the individual structure of the patient’s eye, and it avoids potential irregularities that are sometimes caused by even the sharpest blade. These irregularities can negatively impact post-operative visual acuity. Although the blade method is safe and precise, the IntraLase Method™ has been proven to further improve the outcome for LASIK patients. Clinical studies have shown that patients treated with the IntraLase Method achieve vision that is significantly better than that of patients treated with the conventional microkeratome blade. In particular, IntraLase® patients are better able to see in low light and other visually demanding situations.

The principle advantages of IntraLase® in comparison to the conventional LASIK procedure are fourfold. First, the procedure virtually eliminates most severe LASIK complications. Second, clinical studies show that IntraLase® reduces dry eye symptoms by 72%. Third, IntraLase® reduces the prevalence of irregularities from blade cutting that sometimes cause astigmatism and other problems. Finally, because the procedure uses a thinner flap, patients with thin corneas who would not be good candidates for the conventional microkeratome surgery can now have LASIK.

Facts About IntraLase®

• More IntraLase® patients achieve 20/20 vision
• Patients report better overall vision quality, particularly in low light conditions
• Because IntraLase® allows Dr. Julie Lee to precisely tailor each corneal flap, it improves results for both standard and custom LASIK procedures
• The IntraLase Method™ is preferred by leading doctors, hospitals, and four out of every five patients
• There have been about a million successful IntraLase® procedures performed
• The IntraLase® procedure takes about the same amount of time as the microkeratome procedure – sometimes less
• In a clinical survey of patients who underwent traditional microkeratome LASIK in one eye and IntraLase® in the other, 75% of patients who expressed a preference preferred the IntraLase®-treated eye

During the CustomVue™ procedure, also known as custom LASIK, Dr. Julie Lee uses the WaveScan Wavefront® System, created by VISX®, to create a detailed three dimensional image of the cornea before performing the LASIK procedure. The WaveScan® technology produces a WavePrint® map much like a fingerprint, which is unique to your eye. The WaveScan® digital information is then transferred to the VISX® STAR S4 excimer laser, allowing Dr. Julie Lee to reshape the cornea with an unsurpassed level of accuracy and precision.

The VISX® STAR S4 excimer laser system has both active and passive tracking mechanisms that allow Dr. Julie Lee to deliver this level of accuracy and precision. The ActiveTrak™ system tracks the eye’s movements in three dimensions throughout the procedure, allowing fine-tuned mid-surgery adjustments that make precise results possible. Additionally, iris registration technology records unique landmarks on the iris in order to align the laser properly for treatment. The eye can rotate several degrees between mapping and surgery, but with iris registration this is no longer a concern.

The results from custom LASIK are impressive. This level of accuracy and precision provides you with the potential to achieve a level of vision that very often surpasses what can be achieved with glasses or contacts. With the CustomVue™ procedure, 98 percent of patients are able to achieve 20/20 vision or better without contacts, according to FDA studies.

Most individuals 18 years of age if strictly myopic and over 21 years old with myopia, hyperopia, and/or astigmatism are candidates for laser vision correction. A patient’s vision must be stable for at least a year before undergoing laser vision correction.

Individuals who have degenerative or autoimmune diseases, or who have a condition that slows healing, are not good candidates for laser vision correction. Pregnant women and nursing mothers should wait until they are no longer pregnant or nursing before having laser vision correction. Patients with severe dry eyes or with a previous history of herpes corneal infection are not good LASIK candidates.

If you are interested in reducing your dependence on contacts or glasses, contact Dr. Julie Lee today for a comprehensive evaluation.