What is PRK? PRK is a technique used to perform Advanced Surface Treatment (AST). In PRK, no flap is made like in the IntraLASIK procedure. Instead, in the PRK procedure, the surface epithelium cells are removed in the center of the cornea in a 7 to 9 mm diameter area, the cells are then discarded and the excimer laser treatment is delivered directly to the exposed surface. The surface cells will then be regenerated naturally by the cornea. While the eventual vision result is the same as that obtained with the IntraLASIK technique, the vision recovery is slower and there can be more discomfort after surgery with the PRK technique. Both eyes are usually operated on simultaneously, but some patients will choose to have surgery on one eye at a time to allow the patient to function better with the unoperated eye. PRK is the procedure of choice in eyes that have greater risk such as thinner central corneal thickness, corneal irregularity, dry eye syndrome, and other issues. These risk factors are determined during the thorough preoperative evaluation process in every patient and recommendations are discussed in great detail prior to designing the safest treatment plan for each patient.
Has anyone experienced blindness from laser vision correction? Over 10 million eyes have undergone laser vision correction in the United States since the first procedure in 1987, and there is no reported incident of blindness in any of our over 50 TLC centers or anywhere on the North American continent.
What are the risks of PRK surgery? Like any surgical procedure, you should be fully aware of the risks. Fortunately, complications are rare with the techniques which we use at our center and serious problems occur in less than 1% of procedures. Potential complications include pain, blurriness, infection, night glare and halos, haze or scarring in the cornea, overcorrection and undercorrection, dry eye syndrome, keratoectasia (corneal thinning), and others. We will thoroughly educate you about and review with you the risks of the procedure.
What are the long term side effects of PRK surgery? So far there are no long term side effects which have been identified. The first patient treated with excimer laser in 1987 is still 20/20 today. Most of the problems with PRK occur within the first six months after surgery and it is felt that the results you achieve by one year will remain.
Does the procedure take long and will I miss work? The actual surgery takes 10 to 15 minutes per eye and usually both eyes are treated on the same day. Most patients are back to driving and reading in 3 to 4 days, and back to work in 4 to 5 days. The soft contact lenses which are placed on the eyes after surgery are usually ready to be removed on day #5 or #6 after surgery.
Does the PRK procedure hurt? Numbing drops are used and, if desired, a sedative can be given before surgery. You may feel some pressure during surgery but there is no pain. After surgery, there are usually 3 days of significant irritation, foreign body sensation, tearing and light sensitivity. Oral and topical pain medications and soft contact lenses assist with the pain control.
How will I care for my eyes after surgery? Contact lenses are placed at the conclusion of surgery in order to promote surface regeneration and control pain. Immediately after surgery and for several days you will be using eye drops to prevent infection, add moisture, control pain, and promote healing. You should try to close your eyes as much as possible for several hours following the surgery. You should keep the eyes covered at night with eye shields while the contact lenses are in place. Also rubbing and squeezing the eyes should be avoided to protect the contact lenses. Artificial tears eye drops are helpful for dryness and healing for the first several weeks after surgery. Oral pain control medications are a necessity, Vitamin C pills are given for several months to prevent haze formation.
Can I expect to see 20/20 immediately after surgery? The vision will be better after surgery almost immediately in most cases but still quite fuzzy. It will be about the same on day #1 but will usually become more blurry on postop day #1 and #2 before it begins its slow and continual improvement over the next several weeks. Usually the vision is adequate to drive on day #3 or #4 and good for reading and work on day #4 or #5. Functional vision is usually achieved within the first week; it will generally take 4 to 8 weeks for complete regeneration of the corneal surface and therefore the sharpest vision is usually achieved at this time. No patient should expect exactly 20/20 in both eyes although many achieve this. It is not necessary to have exactly 20/20 vision in both eyes to be very happy with the results and independent of corrective lenses for distance vision activities.
Does the PRK correct Presbyopia (over 40 near vision)? At this time, excimer laser technology does not prevent or correct the near vision changes which occur after the age of 40 in humans. These physiologic changes are going to occur regardless of having laser surgery. Monovision (see below) is one technique used to deal with presbyopia. There is a procedure called NearVisionCK (see website) which can be performed for presbyopia. These techniques do not correct presbyopia but delay the need for reading glasses for many years and sometimes permanently.
What is monovision? Monovision is a technique using either contact lenses, intraocular lens implants or laser vision correction to correct one eye (the dominant eye) for distance and the other non-dominant eye for near. If one is successful with this technique using contact lenses, then it is very likely that one will be successful with monovision created with laser vision correction. Glasses for near vision assistance may still be needed for very small print or later in life. With this technique, the near eye is blurry at distance but the brain is able to balance the disparity between the two eyes. A trial of monovision contact lenses is usually suggested for interested patients before proceeding with monovision laser vision correction.
Will I need to be retreated? Less than 5% of our patients will need more treatment for full correction with what is called an enhancement procedure. When needed, this is usually performed after 4 to 6 months. A second PRK procedure is used and the excimer laser is used to reshape a more tissue but usually only a fraction of the original procedure.
What is CUSTOM treatment? From 1996, when the excimer laser was first approved for use in the US by the FDA, until 2003, all treatment procedures were performed using what is now referred to as "conventional" or "traditional" treatment. Measurements of the so-called Lower Order Aberrations (LOAs) such as myopia (nearsightedness), hyperopia (farsightedness) and astigmatism were used to calculate the number of pulses of laser energy needed to reshape the cornea enough to make one independent of corrective lenses for distance vision. These pulses were applied to the entire surface in a mostly uniform fashion within the desired treatment zone to correct these LOAs. In 2003, the FDA approved the use in the US of Custom treatment for myopia and astigmatism in the low to moderate ranges only. Custom treatment as it is called is a newer way of both measuring and treating the human visual system to eliminate refractive error. It takes advantage of astrophysical technology used to produce telescopes designed for viewing distance stars and the spaces beyond. The system uses ??wavefront?? technology to measure and treat not only LOAs, but also Higher Order Aberrations (HOAs) such as coma, spherical aberration, trefoil and others. HOAs are not taken into account when evaluating and treating the optical system with conventional treatment. The waveprint (or fingerprint of the eye as some have called it) measurement takes readings at almost 200 different points in the visual system and then calculates the number of pulses needed to treat the cornea at each of these 200 points to get an individualized treatment for the visual profile of each eye. These measurements are then used to design an individualized treatment program for each eye. The treatment program is transferred from the wavescan machine to the laser computer. The laser is directed by the surgeon to deliver the designed program to the specific cornea. Custom treatment can now be used for all distance vision corrections (myopia, hyperopia and astigmatism).
What are the benefits of CUSTOM treatment? The bottom line results of the advanced technology as it affects the outcomes are proving to be the following:
(1) greater chance for a 20/20 outcome
(2) better quality of overall vision, presumably due to treating both the LOAs and HOAs
(3) better quality of nighttime vision
(4) less need for enhancements
What are the risks of CUSTOM treatment? The procedure, the risks and the complications of laser vision correction surgery are the same whether performed with conventional vs. custom methods. Both conventional and custom treatments can be used with either LASIK (flap) or PRK (surface) techniques.
Is there more than one type of CUSTOM treatment? There are presently several platforms approved by the FDA in the US for delivering Custom treatment. These basically amount to several different companies offering their own version of the technology. All have slightly different methods and devices with slightly different applications of the technology. All had similar results and outcomes as well as risks in their own FDA trials. Therefore, all accomplish the same results by slightly different means. At TLC/Charlotte, we use exclusively for Custom treatment the CUSTOMVUE system by VISX, which happens to be the most commonly used system worldwide.
How can I find out more and / or make an appointment for an evaluation? Dr. Jaben will do a LASIK evaluation, help you determine your candidacy, determine the procedure that is right for you, and discuss your expectations. You may call 704-295-3777 and leave a voicemail message for Dr. Jaben's Refractive Surgery Coordinator, KARON PETTY, to assist you with your questions and concerns or you may contact her via her email address at firstname.lastname@example.org.
Where will I have my surgery? Dr. Jaben performs all laser vision correction procedures at the TLC Laser Eye Center in Charlotte located in the Charlotte Eye Ear Nose and Throat Associates office building at SouthPark.