Epi-LASIK offers fast recovery time, improved patient comfort
Surface ablation procedure has many benefits, including limited complications and minimal postop pain, surgeons say.
Epi-LASIK is a viable alternative to PRK with alcohol or mechanical scraping, boasting faster recovery time and pain that is manageable with medication, several surgeons said.
Elizabeth A. Davis, MD, FACS, David R. Hardten, MD, and Richard L. Lindstrom, MD, all practicing at Minnesota Eye Consultants, have been performing epi-LASIK with the Moria microkeratome for about 6 months. In separate telephone interviews with Ocular Surgery News, they said the procedure is easy to use and has limited complications. Although LASIK remains important in their practice, epi-LASIK has become the main surface ablation procedure, they said.
“What we’ve found is that the visual recovery is a little bit faster than PRK, maybe on the order of a day or a day and a half faster,” said Dr. Davis, an OSN Practice Management Section Member. “Faster visual recovery is probably the biggest benefit.”
Dr. Hardten, an OSN Corneal/External Disease Section Member, said epi-LASIK makes epithelial edges that are well-demarcated. These edges could explain why the healing process is faster than with PRK, which uses alcohol or mechanical scraping to remove the epithelium. He said the best candidates for the procedure are those who qualify for surface ablation but cannot have LASIK, such as those who have thinner than normal corneas. Although femtosecond laser technology may expand the number of patients who can have LASIK, including some with thin corneas, surface ablation procedures are best in some cases.
According to Dr. Lindstrom, OSN Chief Medical Editor, when surface ablation is indicated or patients request a surface ablation procedure, he now uses epi-LASIK routinely.
“I still do a lot of LASIK, and our group still does a lot of LASIK,” he said. “We’re impressed with the outcomes that we get from femtosecond LASIK, but when it comes to doing a surface ablation, I’m impressed that epi-LASIK is a significant advance over alcohol-assisted manual removal.”
Benefits of epi-LASIK
Dr. Lindstrom said the epi-LASIK procedure has several measurable benefits, including faster visual recovery and more rapid epithelial wound closure.
The most important benefit is that the faster visual recovery allows bilateral procedures. He and colleagues have found that with epi-LASIK, 60% of eyes have 20/40 or better UCVA on the first-day postop. In contrast, eyes that had alcohol-assisted manual removal were in the 20% range, he said.
At 3-days postop, about 75% of patients were 20/40 or better; at 1 week, 90% of patients were 20/40 or better. For bilateral epi-LASIK, the numbers increased to 75% of patients seeing 20/40 or better at 1 day. Many patients can drive themselves back to the office after the procedure, a major convenience for patients, he said.
“Some patients ask to go back to work the day after surgery, which was not the case when I was doing alcohol-assisted epithelial removal. Patients usually had to take a few days to a week off. That’s been a real positive for surface ablation patient acceptance,” Dr. Lindstrom said.
Dr. Davis said epi-LASIK is a straightforward procedure with a limited learning curve. The procedure begins with the surgeon placing the low-pressure microkeratome on the eye, making sure to obtain good suction and centration. The microkeratome’s cut proceeds across the cornea in about 40 seconds, creating a circular epithelial flap, which is then removed from the eye.
The procedure takes about 3 to 5 minutes on each eye, she said. After the flap is removed, the ablation is performed and a bandage contact lens is placed.
Dr. Hardten emphasized that the microkeratome should be well- centered. He said, just as with LASIK, it is important to carefully examine the limbus and pupil for centration and for a “hinge” for the epithelium.
“For most of the patients, I go ahead and take the epithelial sheet off, so I try to center the cut of the epithelium and the removal of the epithelium on the pupil, so I have a nice, large area for the ablation,” he said. “In most cases, with the procedure itself, you get an area of exposure of the stroma that’s adequate for the ablation. But in some patients, if you didn’t get it properly centered or the flap is smaller than desired, then you may need to move the epithelial manually in some areas, to make sure you have exposure of Bowman’s layer and the stroma to all areas you’re going to be treating with the laser.”
A pseudo-decentration effect can be created if the epithelium obscures the section of the cornea that must be ablated with laser, Dr. Hardten said. Carefully examining the area can ensure that there is enough space to treat, after removal of the epithelial sheet.
After the ablation, Dr. Davis said she irrigates the cornea with chilled balanced salt solution, which creates an anesthetic effect, and places a bandage contact lens. Her patients use nonsteroidal anti-inflammatory Xibrom (bromfenac, Ista Pharmaceuticals) twice a day for 3-days postop. She also gives them a prescription for oral Vicodin (acetaminophen, hydrocodone, Abbott Laboratories) or Percocet (oxycodone, acetaminophen, Endo Pharmaceuticals), but said patients often do not need those pain medications. Additionally, patients use Zymar (gatifloxacin 0.3%, Allergan) and Pred Forte (prednisolone acetate 1%, Allergan) four times per day. Topical lubricating drops such as Optive (carboxymethylcellulose, Allergan) are also used hourly for the first several days and then four times daily for several months.
Dr. Hardten said he uses mitomycin-C and irrigates after ablation, just as he would after normal PRK. He prescribes GABA (gamma-aminobutyric acid) drugs such as Neurontin (gabapentin, Pfizer) or Lyrica (pregabalin, Pfizer) to help reduce discomfort. He prescribes those medications, in addition to nonsteroidals such as Acular LS (ketorolac tromethamine ophthalmic solution 0.4%, Allergan), three or four times on the first-day postop, two or three times on the following day and once or twice after that. He also puts on a soft contact lens, in addition to adequate lubricants, an antibiotic and steroid.
Dr. Hardten said the resulting recoveries have been slower than with LASIK but better when compared with PRK.
“The results for us have been good, in the long run,” he said. “The main pearl is giving the oral Neurontin or Lyrica and lots of lubricants, contact lens, Acular LS. I think the oral GABA drugs are one of the more amazing innovations for our patients with surface laser procedures over the last few years.”
According to Dr. Hardten, some patients have slower recovery than others, and when their epithelium heals, they can have a central ridge of epithelium that causes distortion or blurring of vision. Managing the ocular surface before surgery is the best way to prevent problems after surgery. He recommended adequate lubricant and careful attention to lid hygiene to assist in prevention. For patients with pre-existing dry eye, it is best to be aggressive with medications, such as cyclosporine and tears, before surgery to treat those conditions, to prevent postop problems, he said.
Dr. Lindstrom also said chilled balanced salt solution, nonsteroidals, topical tetracaine for breakthrough pain and drugs such as Neurontin have been effective in treating postop pain for his patients.
“Some surgeons have reported less pain with epi-LASIK than with standard PRK. We basically found minimal pain with either standard PRK or epi-LASIK because of our medical regimen,” Dr. Lindstrom said. “It has been a significant benefit to our patients to have the faster visual recovery and more rapid epithelial healing. This has made us more comfortable recommending bilateral, same-day surface ablation, which is a convenience for patient, surgeon and laser center.”
He said some doctors are concerned about epi-LASIK because it is performed with a mechanical device that could create a “nick” in the Bowman’s layer. He has not seen this as yet with the procedure, but it has been reported. He uses mitomycin-C in patients with refractive error of –4 D or higher.
Despite all of the benefits, Dr. Lindstrom said any form of surface ablation can still cause haze, what he called the procedure’s biggest downside. However, that is outweighed by the procedure’s excellent results.
“One of the objections to surface ablation is pain, and we’ve learned how to manage that,” Dr. Lindstrom said. “The other is slow visual recovery, and the Moria device has speeded up visual recovery. It’s still not as fast as LASIK, but it’s a lot faster than the surface ablation we use to perform. In addition, the cornea re-epithelialized faster. Those pluses of epi-LASIK make me less resistant to doing surface ablation.”
For more information:
- Elizabeth A. Davis, MD, FACS, can be reached at Minnesota Eye Consultants, 9801 Dupont Ave. South, Bloomington MN 55431; 952-567-6067; fax: 952-885-9942; e-mail: firstname.lastname@example.org. Dr. Davis is a consultant for Ista Pharmaceuticals and Allergan.
- David R. Hardten, MD, can be reached at Minnesota Eye Consultants, 710 E. 24th St., Suite 106, Minneapolis, MN 55404; 612-813-3600; fax: 612-813-3658; e-mail: email@example.com. Dr. Hardten is a consultant for AMO-VISX, TLCVision and Allergan.
- Richard L. Lindstrom, MD, can be reached at Minnesota Eye Consultants, 9801 DuPont Ave. S, Suite 200, Bloomington, MN 55431; 952-888-5800; fax: 952-884-2656; e-mail: firstname.lastname@example.org. Dr. Lindstrom is a consultant for Advanced Medical Optics.
- Erin L. Boyle is an OSN Staff Writer who covers all aspects of ophthalmology.