Photorefractive Keratectomy (PRK)
Photorefractive Keratectomy - PRK
PRK, or Photorefractive Keratectomy, is approved to treat low to moderate amounts of nearsightedness, farsightedness, and astigmatism by removing tissue from the surface of the cornea. The outcome of PRK is similar to that of LASIK, and most people achieve 20 20 or better vision with PRK; however, it has been argued that LASIK is safer than PRK because there is less risk of corneal scarring. Here at Chicago Cornea Consultants, our surgeons use Mitomycin-C to treat and prevent corneal haze following PRK, so patients can feel confident and at ease with their decision to undergo surgery.
During the PRK procedure at Chicago Cornea Consultants, the patient s eye is numbed using a topical, or eye drop, anesthesia. Then, the surgeon removes the epithelium, a thin layer of protective skin that covers the cornea. This may be done with a blade, a brush, or even the excimer laser, but most commonly is performed with a diluted alcohol solution. During the actual PRK procedure, the patient stares at a fixation light. In less than a minute, the laser removes the precise amount of tissue while it reshapes the surface of the cornea.
Immediately after PRK, a soft contact lens is placed on the eye while the cornea heals. Because the epithelium was removed, patients may experience blurry vision for three to five days after PRK and a moderate amount of discomfort until the epithelium heals and covers the treated area. Various eye drops and oral medications are effective in reducing this post operative discomfort. Final visual results after PRK may not be fully realized anywhere from several days to a few weeks or more as the surface heals in accordance to each individual s healing tendencies.
If you want to learn more about PRK, contact Chicago Cornea Consultants in Chicago, Highland Park and Hoffman Estates to schedule a consultation.
A problem that has plagued PRK in the past has been corneal scarring following PRK for very high amounts of nearsightedness. The surgeons of Chicago Cornea Consultants, Ltd. pioneered the internationally accepted strategy for the treatment and prevention of corneal haze following PRK, utilizing Mitomycin-C (MMC).
Mitomycin-C is an antibiotic chemotherapeutic agent that is used to treat patients who suffer from corneal scarring after PRK. Mitomycin-C can also be used during PRK to prevent corneal haze after the procedure. Mitomycin-C works by inhibiting DNA synthesis, helping to reduce corneal haze after PRK.
Before PRK, the Mitomycin-C is placed in a disposable contact lens vial. A corneal light shield, or sponge, is placed in the Mitomycin-C solution, and after PRK is complete, the sponge is placed on the central cornea and left in place for up to a minute.
Although Mitomycin-C is an effective treatment for corneal haze and scarring, there is no guarantee that haze will not develop after PRK. It is important that you discuss all of your options with us before making a decision. To learn more about our publications relating to Mitomycin C, please view the information and/or bibliographies on Randy Epstein or Parag Majmudar.
The History of Refractive Surgery Ophthalmic surgeons have been performing refractive surgery for the treatment of myopia (nearsightedness), hyperopia (farsightedness), and astigmatism (irregular shaped cornea) for approximately 100 years, but the past decades have produced rapid change and growth by means of refined techniques and the emergence of laser vision surgery. In 1978 a refractive procedure called Radial Keratotomy (RK) was introduced in the United States. RK involves making of a number of cuts in the cornea to change its shape and correct refractive errors. Following the introduction of RK, doctors routinely corrected nearsightedness, farsightedness, and astigmatism using various applications of incisions on the cornea. In the 1980s a new type of laser called the excimer laser was developed. Though originally used to etch computer chips, ophthalmologists began using the excimer laser successfully in refractive surgery techniques to remove very precise amounts of tissue from the eye's surface. Excimer lasers revolutionized refractive surgery by providing a degree of safety and precision that was previously unattainable with other techniques.