For most of us in the tri-state region and especially New York, PRK or LASEK or epi-Lasik seem to be less-than ideal vision correction procedures simply because the healing time is longer than with LASIK. Most people want to enjoy the benefits of laser vision correction as quickly as possible and return to their regular routine promptly, so if they are candidates for LASIK that is what they choose. However for many reasons surface ablation techniques like PRK, LASEK, and epi-Lasik may be preferable. When we talk about any of these three procedures we are really talking about essentially the same thing with very minor differences in the actual surgical technique giving rise to the different names. For the consumer, they may be considered one in the same – a procedure in which no true corneal flap is made and so the laser pulses are applied to the ‘surface’. (In LASIK a corneal flap is made and the pulses are applied to the ‘middle’ of the cornea and then the flap is repositioned.)
After the PRK, LASEK, or epi-Lasik procedures, the surface epithelium (skin) of the cornea has to grow back and so the first few days can be uncomfortable and the vision variable. (In LASIK, this layer is preserved.) As healing continues the vision generally improves over the first few weeks and months. Usually by the third to fifth day the vision is good enough, and the patient comfortable enough, to return to work, school, or other normal activities. (It is sometimes hard to convince New York, New Jersey and Connecticut workers to take a few days off.…) Advanced surface ablation techniques like these are used for people with thinner corneas, in some situations where the corneal shape is less than ideal, or where the patient prefers not to have a corneal flap. These techniques leave a thicker base to the cornea after laser correction since the treatment starts at the surface. This is important in thin corneas.
PRK/LASEK/epi-Lasik are not always indicated in people with large prescriptions because there is an increase in the possibility of corneal haze formation, which can cause a decrease in vision and increased side effects like glare and halo. With the use of mitomycin C , along with the newer scanning spot lasers, their incidence is decreased.
LASEK and epi-Lasik were developed in the hope of avoiding the major drawbacks of PRK: the discomfort and long healing time. This proved not to be the case. However, because the corneal base is left thicker and there is no flap made, PRK/LASEK/epi-Lasik may be safer. However, in experienced hands, the risk of flap complications in LASIK with the newer microkeratomes (flap makers) is minimal. Fortunately, the final visual results with PRK, LASEK, epi-Lasik and LASIK are equivalent and the major disadvantages of the surface ablation techniques can be minimized.