Freedom from the dependency of glasses and contact lenses can be for many individuals a very liberating experience. Athletic and leisure pursuits are enhanced without the encumbrance of these devices.
Several refractive surgical options are available to treat a variety of refractive errors. Discussed below are LASIK Surgery and the STAAR Visian ICL.
Laser Assisted Stromal in Situ Keratomileusis is a type of refractive surgery that incorporates the technology of advanced lamellar keratoplasty with the Excimer Laser. It has been performed clinically since 1991 world-wide, with millions of patients having undergone this procedure with excellent results. The surgery is designed to eliminate or reduce your dependency on glasses or contact lenses. LASIK can correct nearsightedness (myopia), farsightedness (hyperopia), and astigmatism. To understand how LASIK offers certain advantages among a variety of refractive procedures, it is important to understand the structure of the cornea. The human cornea is comprised of five layers: Epithelium, Bowan's Membrane, Stroma, Descemet's Membrane, and Endothelium.
More than 90% of the cornea is made of Stroma, a series of parallel collagen lamellae arranged in perfect molecular registration to provide optical clarity. In addition, the cornea has an intrinsic curvature which works in conjunction with the crystalline lens behind the iris to focus light on the retina. If light rays can focus on the retina without the aid on an optical device, the eye is considered Emmetropic for distance. However, if light naturally focuses in front of the retina, the eye is Myopic. If light focuses behind the retina the eye is Hyperopic. And if two planes of light 90 degrees apart do not focus on the retina, then Astigmatism is present.
LASIK is a refractive surgical procedure having as its hallmark the creation of a corneal flap followed by laser ablation of the underlying tissue to change the refractive power of the eye. The procedure is initiated with a microkeratome, an instrument analogous to a carpenter's plane, to create a partial corneal flap (called a partial keratectomy) which retains the Epithelial layer, Bowman's membrane and a portion of anterior Stroma. The suction ring is first placed on the cornea. The ring has dove tails which are engaged by the microkeratome to allow it to track very smoothly and accurately across the cornea generating a hinged flap similar in dimensions to that of a hard contact lens: 9.0 mm in diameter by 130-140m in thickness (0.130 - 0.140 millimeters). The design of the ring allows the hinge to be placed at any clock hour; however 99.9% of the time the hinge is positioned superiorly creating an up-down flap. Since the Moria C-B Microkeratome has five suction rings with different curvatures, an optimally-sized flap can be generated no matter what the curvature of the cornea is.
The flap is then reflected upward and the underlying stroma is ablated with the computer generated excimer slit-scanning beam. The flap is then returned to its original orientation.
To determine if you are a candidate for LASIK Surgery you will require a series of measurements that will be performed in the office. These tests will determine the amount of refractive error that needs to be corrected, the corneal thickness, the degree and uniformity of your corneal curvature as well as the general health of your eye. The gold standard used to acquire this information is the Pentacam, a device that takes Scheimpflug slit photographs of the eye to create important diagnostic corneal maps of thickness and elevation, as well as generating other important corneal data. In addition, the Nidek OPD-Scan is used to generate wave front information for custom cornea ablation. We are currently using a custom corneal ablation profile that reduces one of the major corneal aberrations and at the same time limits the amount of tissue removed.
However, if your corneal thickness as determined by the Pentacam is thin, it still may be possible to achieve excellent vision using a new technology: the STAAR Visian ICL . The STAAR Visian ICL is an implantable lens designed for those individuals who are not suitable candidates for LASIK Surgery. More than 30,000 of these lenses have been implanted worldwide. The FDA has recently granted approval for the use of this lens in the U.S. for refractive errors of -4.00 diopters to -20.00 diopters.
The STAAR Visian ICL is made of a soft biocompatible co-polymer designed to be easily implanted through a small self-sealing corneal incision. The ICL is engineered to be positioned behind the iris, vaulting over the natural crystalline lens of the eye.
Dr. Rubman is one of the most experienced refractive surgeons in the United States, particularly in the use of the microkeratome, having used this instrument in thousands of lamellar procedures since 1983. LASIK Refractive Surgery is performed in the office under topical anesthesia using the Nidek EC-5000 Excimer Laser, using slit-scanning technology to provide an extremely smooth photoablation.
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