|Since refractive surgery technologies received FDA approval 10 years ago, they have become further developed and varied in order to improve visual outcomes, increase safety, and reduce intra- and postoperative complications. One of the latest advances in refractive technology is EpiLase (also known as Epi-LASIK, Epi-K, advanced surface treatment, or advanced surface ablation).|
The other names, in my opinion, did not adequately describe the procedure and confused patients. My husband and I coined the name EpiLase for this procedure and trademarked it. This laser vision correction is performed on the surface of the cornea. EpiLase melds the benefits of PRK and LASIK but eliminates most of the disadvantages.
I currently perform EpiLase using the Moria Epi-K epithelial separator (Moria, Antony, France). As of January 2007, EpiLase represented 60 of my refractive surgery cases, a 50 increase from the previous year. Initially, I was only using this procedure for patients with thinner-than-average corneas or dry eyes or those at increased risk for disturbed flaps (eg, athletes). I also favored this procedure for patients with subtle topographic and mild clinical abnormalities and for younger patients whose topographies were too immature to illustrate abnormalities. Increasingly, I am seeing patients who are excellent LASIK candidates asking for EpiLase because they do not want a corneal flap.
This article describes my EpiLase technique.
THE EVOLUTION OF ADVANCED SURFACE ABLATION OR EPILASE
EpiLase differs from PRK in that there is no scraping of the epithelial cells; instead, an epikeratome produces a smooth corneal bed. There is less subjective pain and a faster recovery associated with EpiLase than with PRK.
THE EPILASE PROCEDURE
Typically, I offer customized laser vision correction (if the patient is a good candidate) with the Visx WaveScan Wavefront System (Advanced Medical Optics, Inc., Santa Ana, CA). Because customized treatments remove more tissue, EpiLase is a particularly good option for patients who otherwise are not candidates for laser vision correction, such as high myopes.
With a Weck-cell sponge (Medtronic Xomed Ophthalmics, Inc., Minneapolis, MN), I gently move the epithelial sheet to the side of the cornea. I wipe the bed and ensure that the sheet has been completely removed. Next, I complete the laser ablation. If it is deeper than 65 µm, I will apply mitomycin C 0.02 for 15 to 30 seconds. I rinse the cornea with balanced salt solution and then place chilled balanced salt solution in an alcohol well on the cornea for 30 seconds. I have found that cold balanced salt solution decreases patients' pain postoperatively.
Next, I apply a bandage contact lens. I prefer to use the Acuvue Oasys (Johnson & Johnson VisionCare, Inc., Jacksonville, FL). I treat the patient's second eye in the same manner.
The postoperative drug regimen I prescribe includes Lyrica (Pfizer, Inc., New York, NY) 75 mg b.i.d., an antiepileptic drug that also controls pain. Alternatively, surgeons may prescribe 300 mg of Neurontin (Pfizer, Inc.) t.i.d.
I also use Xibrom (Ista Pharmaceuticals, Inc., Irvine, CA) b.i.d. because of its anesthetic effect. I find that Xibrom in combination with Lyrica works very well. Informal surveys of my patients indicate that, after 1 or 2 days of this combined treatment, they no longer require either of the medications.
I also prescribe Zymar and Pred Forte (both from Allergan, Inc.) q.i.d postoperatively. I stop the antibiotic after the patient's eyes have re-epithelialized, and I generally have the patient use the steroid for 3 weeks after surgery. With PRK, my patients used the steroid for 3 to 4 months postoperatively and 1,000 mg of vitamin C for 3 months.
In my experience, the incidence of postoperative dry eye is less with EpiLase than LASIK. If a patient's vision is not at as should be postoperatively, however, and he refracts well but has a dry cornea, I will also prescribe Restasis. Many of my EpiLase patients are having a surface procedure precisely because they have dry eyes. I have started these individuals on Restasis and perhaps even placed punctal plugs preoperatively in an effort to prepare them for surgery. I have found that most patients require a minimum treatment of 6 months with Restasis after EpiLase. Only a few of my patients required ongoing therapy for their dry eyes. These were generally patients with a preexisting condition. Combination therapy with Restasis and punctal plugs quickly rehabilitates EpiLase patients who have dry eye. I also have them use preservative-free artificial tears q.i.d. for approximately 1 to 2 months at least.
I have seen a change in my patients' attitudes toward laser vision correction. Many simply do not want a corneal flap or a corneal-scraping procedure. Surgeons need to keep an open mind about utilizing newer surface procedures. My own attitude has certainly changed. Two years ago my predominant procedure was LASIK. I now am very open and enthusiastic about having multiple refractive options for the right patients.
Whether a surgeon performs EpiLase, PRK, or LASIK, each procedure has its own set of risks and benefits. Although I have not turned my back on LASIK and still perform the procedure on suitable patients, my threshold for "going to the surface" certainly is much lower these days.
In my practice, if anything in a patient's preoperative workup, mapping, or examination gives me pause, I plan EpiLase for him. I do not even give it a second thought.
Jacqueline D. Griffiths, MD, is Medical Director of NewView Laser Eye, Inc., in Reston, Virginia. She acknowledged no financial interest in the companies or products mentioned herein. Dr. Griffiths may be reached at (703) 834-9777; firstname.lastname@example.org.