LASIK patients should make their doctor aware of certain eye problems including amblyopia (lazy eye), strabismus (muscle imbalance), severe dry eyes, previous eye surgery or injury, or any recurrent, residual or active eye conditions which may affect healing. Other conditions that should be related to the doctor include keloid scarring with previous surgical healing, back problems, claustrophobia or other psychological problems, which may affect the surgery or recovery.
It is critical that a potential laser vision correction candidate has obtained a stable ocular prescription for at least one year. Since hormones may affect the stability of your prescription, pregnant or nursing women are not eligible to pursue LASIK surgery until two menstrual cycles after nursing has been discontinued. This is to make sure that the best results are achieved with the surgery, and to try to limit fluctuations in prescription that can occur with hormonal shifts.
It is important that anyone considering LASIK has realistic expectations. LASIK allows people to perform most of their everyday tasks without corrective lenses. However, people looking for perfect vision without glasses or contacts run the risk of being disappointed. Over 90% of people who have LASIK achieve somewhere between 20/20 and 20/30 vision without glasses or contact lenses. If 20/20 vision is essential for your job or leisure activities, consider whether 20/30 vision would be good enough for you. You should be comfortable with the possibility that you may need a second surgery or that you may need to wear glasses for certain activities, such as reading or driving at night. LASIK cannot correct presbyopia, the age-related loss of close-up focusing power.
A type of refractive surgery to improve vision, conventional Lasik makes use of a small blade and a laser. The blade, known as a microkeratome, is used to make cut thin, circular flap in the cornea that is folded back out of the way. The surgeon then uses an excimer laser to reshape the cornea. An excimer laser is a precise cool ultraviolet beam that removes very small pieces of the cornea. Patients with myopia (nearsightedness), hyperopia (farsightedness), and astigmatism (abnormal curvature of the cornea) can all find improved vision with Lasik. Patients with myopia will have their corneas flattened, while patients with hyperopia will have their corneas steepened. Astigmatism is corrected by smoothing the cornea into a more regular shape.
In the Conventional LASIK and Bladeless LASIK laser vision correction procedures, a flap of corneal tissue must be created and then folded back. The cornea is the transparent dome-like structure that covers the iris and pupil of your eye. By creating a flap in the cornea, the LASIK surgeon is able to perform the laser vision correction treatment on the inner layer of the cornea and allows for a rapid visual recovery.
With Bladeless LASIK, the LASIK surgeon uses a laser to create the corneal flap. This technology enables the LASIK surgeon to customize the corneal flap for every patient. In recent studies done by IntraLase, this technology may now make it possible to treat those who were previously dismissed as non-candidates due to thin corneas.
Photorefractive Keratectomy has been performed since 1986. Prior to LASIK, PRK was the most commonly performed laser vision correction procedure. PRK differs from LASIK as no flap is created during the PRK procedure. PRK may be suitable for people with larger pupils, thin corneas, have other corneal issues, or dry eyes.
For the PRK laser vision correction procedure, no scalpels are used and no incisions are made. Prior to the procedure, an extremely detailed map of your eyes’ surface is created by a computer and then used by your PRK surgeon to calibrate the excimer laser to your exact prescription.
To accomplish the reshaping, the surgeon first removes the protective surface layer (epithelium) from the cornea. The epithelium is regenerated within three to five days.
Your PRK Surgeon will then smooth the area and proceed with applying computer controlled pulses of cool laser light to reshape the curvature of the eye. Deeper cell layers remain virtually untouched.
The PRK laser vision correction process is completed in approximately 30 to 60 seconds, and immediately afterwards, a clear bandage contact lens is placed on the cornea to protect it. Additional eye drops are applied. Since a layer about as slender as a human hair is typically removed, the cornea should maintain its original strength. Often, only one eye is treated per surgery day, although your surgeon may decide to do both of your eyes on the same day.
Post-operatively, PRK patients are placed on antibiotic drops, along with anti-inflammatory agents to promote comfort and reduce swelling. Prescription eye drops are used for several months following the procedure. Patients are also fitted with a bandage contact lens to improve their comfort while their eye is healing. Once the epithelium is healed, usually on the second or third post-operative day, the bandage contact lens is removed by your doctor.
Wavefront procedures treat the same kinds of eye aberrations as traditional Lasik, but generate and use a 3-D map of the eye to design custom treatments. Wavefront is touted for its accuracy and for is ability to improve not only visual acuity, but also contrast sensitivity and fine detail. This is a laser vision correction procedure that enables your LASIK surgeon to further customize the conventional LASIK procedure to your individual eyes. Low-order aberrations such as myopia, hyperopia and astigmatism are responsible for affecting visual acuity while high-order aberrations affect contrast and detail. Currently, only wavefront can correct high-order aberrations. Further, Wavefront Lasik presents a lower risk for post-operative complications such as night glare and halos.
Custom LASIK surgery, often referred to as WaveFront LASIK, uses a technology called a WaveFront analyzer which creates an individualized, 3-dimensional measurement of how your eye processes images. This is used to guide the laser in re-shaping the front part of the eye. Customization results in patients seeing clearer and sharper than ever before and with less incidence of glare and halos.
The actual LASIK part of the procedure is performed in exactly the same way in both Conventional LASIK and Bladeless LASIK. The pre-op testing for Conventional LASIK and Custom LASIK differ greatly. The wavefront analyzer used with Custom LASIK brings a whole new level of knowledge and accuracy to the surgeon.
LASIK, like any surgery, has risks and complications that should be carefully considered. Most complications can be treated without any loss of vision. There is a chance, though extremely small, that your vision will not be as good after the surgery as before, even with glasses or contacts.
Some people experience temporary side effects after LASIK that usually disappear over time. These side effects may include discomfort or pain, hazy or blurry vision, scratchiness, dryness, glare, halos or star-bursts around lights, light sensitivity, or small pink or red patches on the white of the eye. In rare situations, these effects may be permanent. Infection is a small possibility with any surgical procedure, including LASIK. Antibiotics can usually clear up such infections. Rarely, complications during surgery may cause irregularities in the corneal flap, requiring further treatment.