PRK surgery (photorefractive keratectomy) was the first type of laser eye surgery to be performed for vision correction in the United States when it was introduced in 1995.
The newest generation of the PRK procedure is known as LASEK (laser-assisted sub-epithelial keratectomy). LASEK provides a safe and effective option for laser vision correction for persons who desire less dependence on their glasses and contact lenses but who are not appropriate LASIK candidates.
LASEK is also indicated for those who desire additional vision refinement following LASIK or other surgery on their cornea.
At AGEI, our surgeons use the same cool ultraviolet excimer laser for the corneal sculpting step in both LASEK and LASIK, so the final vision results are similar. The distinction between LASEK and LASIK centers around the surgical approach and how this affects your recovery.
The key difference between LASEK and LASIK eye surgery has to do with the first step of the vision correction surgery - the handling of the outermost layer of the Cornea (the epithelium).
In a LASIK procedure, your surgeon begins by creating a thin flap from your cornea’s outer layers (the epithelium) and a thin portion of the underlying middle layer known as the stroma. This flap is then peeled back and laser sculpting is done on the cornea's middle stromal layer. After the sculpting is complete, the flap is repositioned to cover the LASIK surgery site, and the epithelium remains intact.
The bottom line, the primary difference between LASIK and LASEK is that the laser energy is applied directly on the outer surface of the cornea with LASEK, whereas the laser energy is applied to the middle corneal layer with LASIK, thus sparing the corneal surface which results in a faster recovery.
At the start of the LASEK procedure, your surgeon uses anesthetic drops to numb your eye. Next, the outer epithelial layer of your cornea is gently removed and the excimer laser reshapes your cornea. The entire process takes about 10 minutes per eye.
At the end of the procedure, a clear bandage contact lens is placed over the cornea which helps with post-op discomfort, which can be mild to moderate.
Immediately following the procedure, you may feel like there is something in your eye (the protective contact lens) and you may experience tearing, light sensitivity, a moderate amount of blurred vision, and seeing halos around bright objects. That is normal.
These symptoms can last for the first 3 days after surgery and are usually worst on the second and third days following surgery but improve greatly as the corneal surface heals by post-op day four or five.
To help decrease discomfort during the healing process, chilled lubricating and medicated drops that also help promote healing and reduce the risk of scar formation and infection. You won’t be able to drive or work the day of your LASEK surgery. Some patients also feel like they need to take a couple of days from work. This recovery time should be taken into consideration when considering a LASEK procedure.
By the time your bandage contact lens is removed (on postop day 5 to 7), your vision will be much improved, generally ranging between 20/30 and 20/50, depending on the extent of correction done. By then, you will be comfortable enough to return to your daily routine.
As your cornea's surface continues to heal and smooth out over the next 4-6 weeks, your vision will continue to improve. Patients typically achieve their best possible vision at 3 months following surgery. The correction is usually considered to be stable at one-year post-op.
If you are severely nearsighted (with a very high refractive error) a LASEK vision correction procedure might not achieve 20/20 vision. You might still require the assistance of milder eyeglasses to achieve your best vision.
LASEK Involves less depth of laser treatment than with LASIK
More corneal thickness is preserved, so if additional surgery is needed in the future, it can be done
Because there's no corneal flap, the risk of corneal flap complications is eliminated
There are advantages and disadvantages to every surgical procedure. That's why it is important to meet with an eye surgeon in order to get a detailed eye exam to identify your particular vision issues and to obtain accurate information as to which type of refractive surgery would best suit your vision needs and lifestyle.
Kerry K. Assil, MD, is regarded as one of the world’s foremost experts in refractive surgery, having made significant advances in the field with his numerous inventions. Additionally he has the unique distinction of having trained thousands of eye surgeons in the latest refractive surgical techniques.
Dr. Assil has authored more than one hundred textbooks, textbook chapters and articles on refractive surgery and has appeared regularly on major television network news programs as a pioneer in refractive surgery. He also leads educational forums for other eye care professionals, which have included featured lectureships at Harvard University, Johns Hopkins University and Tokyo University.