KOLOA, Hawaii Having a patient sleep for a few hours after LASIK can help to rehabilitate the ocular surface and make the experience more comfortable, according to a presentation here.
Using photorefractive keratectomy (PRK) instead of LASIK in certain patients can also help improve outcomes of refractive surgery.
Its important to rehabilitate the ocular surface, said Richard L. Lindstrom, MD. I think the best thing is what I call nap time. Tell the patients to go home and sleep. If they go home and sleep for 2 to 3 hours, by the time they wake up, the epithelium has grown across the gutter. Their surface has begun to rehabilitate. They will be more comfortable and seeing well.
Dr. Lindstrom gave refractive surgery pearls in a presentation here at Hawaii 2001, the Royal Hawaiian Eye Meeting, sponsored by Ocular Surgery News in conjunction with the New England Eye Center.
He said that PRK can be more effective than LASIK in certain groups of patients.
I find myself going back and doing maybe 3% to 5% PRK. For anterior membrane dystrophy, 8:1 preferred to do PRK. So, its okay to do PRK once in a while, he said.
After LASIK is performed, significant strain is put on the ocular surface. Toxic medications are used on the eye and a keratome is run over it. Also the epithelial defect on the edge of the flap needs to heal.
Weve found the thing that enhances healing the best is simply having the patients go home and sleep. So if they can go home and sleep with their eyes closed for 2 or 3 hours, then that allows the ocular surface to recover, Dr. Lindstrom said.
Sleeping allows the epithelium to grow across the gutter where the flap meets the stromal bed, where the microkeratome has disrupted the epithelium. This growth makes the flap secure so that it will not come loose.
By the time patients wake up after the nap, theyre comfortable. The foreign body sensation, photophobia and tearing they would otherwise have is gone. The surface has had a chance to heal, their vision is better and theyre feeling good, he said.
Learned from experience
According to Dr. Lindstrom, the idea for the nap after surgery came from experience.
Its something that weve promoted and we kind of learned about it from experience, he said. Patients would come back the next day, and some of them would have really good vision, be comfortable and everything was great. Others would come back, and their eyes would be a little sore and they would have some punctate staining. We would ask questions about what they did. The ones who went home and stayed up and watched TV, read a book or used their eyes would be the ones who had sore eyes with blurrier vision and punctate staining on the cornea. The ones who said they just went home and took a nap are the ones who look great. So we started to recommend it.
After the procedure, Dr. Lindstrom gives patients oral Valium (diazepam, Roche) to help them sleep once they return home.
Another tip offered by Dr. Lindstrom was that using PRK instead of LASIK in some instances could help reduce complications after a refractive procedure.
The most common indication I have right now is what I call a funny-looking corneal topography, he said.
Its the cornea that has the non-orthogonal or asymmetric astigmatism or has an asymmetric bow-tie pattern. Often the cornea is a little on the thin side, so if the cornea is less than 500 µm and has non-orthogonal asymmetric astigmatism, the patient does not truly have keratoconus but things look a little bit atypical. Those patients make me nervous with LASIK. I think they are at a higher risk for developing a late corneal ectasia, and we find we do really well with PRK.
Anterior basement membrane dystrophy, a history of recurrent erosion and other factors may also make PRK preferable over LASIK.
On the basement membrane dystrophy patients, PRK is better because it reduces the chances of getting a severe epithelial defect, Dr. Lindstrom said. On the scar patient, its better because you get rid of the scar. Then we have a group of patients who have very deep-set eyes with tight orbits and they are very squeezy. Those patients run the risk of having a bad flap, and sometimes its smarter to do a PRK on them, too.
Even though these cases may do better with PRK, that does not mean the surgeon should put away the microkeratome.
Were not going back (to PRK) for every case, but basically the bottom line is that PRK is and was a good operation, he said.
When you look at the visual acuity results 1 year after the surgery, theyre pretty much the same. We like to do LASIK because the visual recovery is quicker for the patient and its easier on the patient. But, visual recovery is not that difficult with PRK, and if one can avoid a major complication, its worth it. You have to tell the patient that PRK works just as well as LASIK, it just takes a little longer to recover. In the end, youll end up with just as good results, but it will be safer for you. So its a safety issue.
LASIK is still the primary procedure, but it is not the ultimate procedure any longer, he said.
Were still doing 90% to 95% LASIK, but at one time we were doing 99% LASIK, he said. Were finding now 3% to 5% of patients where were beginning to think PRK is a safer operation for them. Were not recommending going from LASIK to PRK as a routine. Were just recommending doing PRK in high-risk cases. Most surgeons know how to do both operations.
Dr. Lindstrom noted that because LASIK is a much more high-profile, highly advertised procedure, some patients may worry when an alternative is suggested.
You have to discuss it with patients, he said. You have to counsel them. Thats part of the art of medicine. If you go to 10 different refractive surgeons, you dont always get the same recommendation. For example, if you have one of those irregular corneas thats a little bit thin, some surgeons would tell you not to have surgery at all, some people would say were okay with LASIK and some people would say wed recommend PRK.
For Your Information:
- Richard L. Lindstrom, MD, can be reached at 710 E. 24th St., Suite 106, Minneapolis, MN 55404; (612) 813-3633; fax: (612) 813-3660; e-mail: firstname.lastname@example.org.