LASIK — Types of Surgery
Many people think that LASIK is the only type of refractive surgery, and today LASIK is the most commonly performed corrective eye surgery in the United States, but in truth, there are many different procedures to choose from. Refractive surgery, also known as corrective eye surgery, encompasses a multitude of procedures designed to treat and correct refractive errors including nearsightedness, farsightedness and astigmatism. In each of these procedures, a laser is used to reshape the cornea to alter the way light rays enter the eye to achieve focus. The process used, however, differs from surgeon to surgeon.
LASIK
Figure 1
Figure 2
Figure 3
Laser in situ keratomileusis, or LASIK, is the most commonly performed refractive surgery procedure today and is the primary procedure of choice at Wolfe Eye Clinic. LASIK has advantages over other procedures, including a relative lack of pain and the fact that good vision is usually achieved almost immediately or in a very short period of time. Those with nearsightedness, farsightedness and astigmatism can benefit from LASIK. During LASIK surgery, a thin flap of tissue is created on the center of the cornea (Figure 1). This flap is then lifted back to expose the internal tissue, or stroma, of the cornea. An excimer laser is then used to reshape the cornea and correct the refractive disorder (Figure 2). The flap is then layed back over the cornea where it heals itself in a very short period of time (Figure 3).
With LASIK, the instrument used to create the flap varies. Most surgeons use an instrument called a microkeratome. A microkeratome is a device that uses a very sharp oscillating blade to cut the flap. Other surgeons, including those at Wolfe Eye Clinic, prefer a more advanced bladeless technique, using a very precise laser to create the flap instead. Wolfe Eye Clinic surgeons use the IntraLase laser to create the flap during LASIK surgery.
PRK
Photorefractive keratectomy, or PRK, was the first refractive procedure that utilized the excimer laser to reshape the front surface of the cornea. It was initially envisioned in 1983 and, after a long series of clinical trials, was approved by the FDA in 1995. PRK however is primarily used to correct mild to moderate cases of nearsightedness and astigmatism. After the eye has been anesthetized with topical eye drops, your doctor prepares the eye by removing the surface layer of the cornea called the epithelium. This layer naturally regenerates itself every few days. Pulses of laser light are then applied to the surface of the cornea to reshape the curvature of the eye. Postoperatively, patients typically wear a bandage contact lens for the first three to five days to reduce postoperative pain and irritation. Anti-inflammatory eye drops are used in a decreasing dose for several months. Vision is usually blurry initially and starts to clear over the first several weeks, while continuing to improve for up to one year.
LASEK
Laser Epithelial keratomileusis, or LASEK, is a laser procedure that is used mostly for people with corneas that are too thin or too flat for traditional LASIK. It was developed to reduce the chance of complications that occur when the flap created during LASIK is not the ideal thickness or diameter. In LASEK, the epithelium, or outer layer of the cornea, is cut not with the microkeratome blade or laser used in LASIK, but with a blade called a trephine. Next, the surgeon covers the eye with an alcohol solution for around 30 seconds. The solution loosens the edges of the epithelium. After sponging the alcohol solution from the eye, the surgeon uses a tiny tool to lift the edge of the epithelial flap and fold it back out of the way. Then the surgeon uses an excimer laser, as in LASIK or PRK, to apply pulses of laser light that sculpt the corneal tissue underneath. Afterward, the epithelial flap is placed back on the eye. There is a possibility of a reaction to the alcohol that may kill some of the epithelial cells. Patients typically wear a bandage contact lens for around four days and may feel eye irritation during the first few days afterward. The time it takes to recover good vision is up to four to seven days longer than with LASIK.
Epi-LASIK
Epi-LASIK is a cross between LASIK and LASEK. During Epi-LASIK, a flap is cut in the cornea’s outer layer, just as in LASIK and LASEK. However, with Epi-LASIK the surgeon uses a blunt, plastic oscillating blade. Instead of the alcohol that is used in LASEK to loosen the epithelial sheet, during Epi-LASIK the surgeon uses the blunt plastic blade, called an epithelial separator, to scrape the sheet across the eye. Next, the surgeon uses an excimer laser, as in LASIK, LASEK or PRK, to apply pulses of laser light that sculpt the corneal tissue underneath. Afterward, the epithelial flap is placed back on the eye. Then, a special contact lens is placed on the eye to keep the flap in place while it re-epithelializes. Vision will probably be cloudy or variable at first, unlike traditional LASIK. Some patients report good vision within a week or two, while others take three to six months to reach their final result. These recovery times are significantly longer than with LASIK, which usually allows people to achieve good vision from the same day up to a few weeks later and to drive by the day afterward.
Lens Implants — An Alternative to LASIK
LASIK surgery is not an option for everyone. A very high refractive error, thin corneas or severe dry eye may prohibit someone from being a good LASIK candidate. Fortunately, implantable lenses may provide an alternative. Examples of these lenses include the Verisyse™ Intraocular Lens, Visian’s Intraocular Collamer Lens, Alcon’s Acrysof® ReSTOR® Intraocular Lens and the ReZoom™ multi-focal Intraocular Lens. Unlike LASIK, which reshapes the outer part of the eye, lens implants are inserted inside the eye. Once in place, the lens stays in place indefinitely and should require no maintenance.
All options will be discussed during the LASIK evaluation to determine which technology is most appropriate for you.
To schedule a LASIK evaluation at any of Wolfe Eye Clinic’s seven main offices in Ames, Cedar Falls, Cedar Rapids, Fort Dodge, Marshalltown, Waterloo or West Des Moines, call Wolfe Eye Clinic’s LASIK hotline at 1-800-237-5393 to speak with our LASIK Patient Service Representative.
