Lamellar-Assisted In Situ Keratomileusis, commonly known as LASIK, has been performed in the United States since the late 1990s. Prior to the introduction of LASIK, photorefractive keratectomy, or PRK, was the main refractive surgery procedure done in the U.S.
PRK vs. LASIK
The difference between the two procedures is that PRK uses an Excimer laser to reshape the eye by applying laser energy to the surface of the cornea. During LASIK, a very thin flap of corneal tissue is created and the Excimer laser is then applied to the cornea to reshape it underneath the flap. The flap is then repositioned onto the corneal bed. LASIK is performed more commonly than PRK in the U.S., mainly due to the more rapid return of vision that occurs with LASIK versus PRK. PRK can also cause slightly more discomfort in the first 24 hours versus LASIK. However, some patients are better candidates for PRK than LASIK for various reasons such as dry eyes.
Since the introduction of LASIK, there have been improvements in the way the procedure has been performed and the results have significantly improved. One of the most profound changes has been the move from creating the corneal flap with a blade to creating it with a laser. The Femtosecond laser is now used in the majority of LASIK cases in the United States. Creating the flap with a laser has improved the safety, consistency and quality of the corneal flaps. This translates into better outcomes for the majority of patients. Our center uses the IntraLase Femtosecond laser made by Johnson & Johnson.
The second significant improvement has been the advent of Customized LASIK. The eye has unique qualities and shapes much like a fingerprint that can be measured by a device called a WaveScan. The WaveScan can detect subtle differences in the contour of the eye and the WaveScan measurement can then be used by the Excimer laser to reshape the eye in a customized manner that results in much more precise visual acuity. Following Custom LASIK, patients many times will relate that their vision is better than they had ever experienced with glasses and/or contacts.
Johnson & Johnson recently released their second generation WaveScan known as the iDesign™. The iDesign™ system creates a 3-dimensional map of the eye which measures and maps the irregularities of the eye that may impact vision. The sensor technology that is used with the iDesign™ system is the same technology being used in the James Webb Space Telescope which will eventually replace the Hubble Telescope in order to transmit high-resolution images of deep space back to Earth.
A recent study by Dr. Amin Ashrafzadeh in Modesto, CA compared LASIK results using the iDesign™ system to the previous WaveScan system. The study showed that patients treated with the iDesign™ system had a 15% improvement in the rate of 20/20 or better outcomes and a 31% increase in the rate of 20/15 or better outcomes. Over 60% of his patients were able to see 20/15 or better using the iDesign™ system.
Our practice evaluated the iDesign™ system last fall and we were quite impressed with the visual outcomes. We are in the process of purchasing the system next month. It will be the only iDesign™ system currently in the state of Kentucky.
I hope that this information has been useful to you. Please contact my office at 502-245-0305 for a free LASIK screening exam to see if you are a candidate for this new and exciting technology!