Refractive surgery experienced great growth and explosive developments this year, according to two refractive surgeons.
Ernest Kornmehl, MD, of Boston said the expansion of LASIK over the past year particularly impressed him. He noted that while 82,100 procedures were performed in the first half of 1997, 201,500 procedures were performed in the first half of 1998--a 145% increase.
"The extended recovery period required for PRK inhibited the growth of refractive surgery. The rapid recovery and minimal discomfort associated with LASIK have allowed laser vision correction to come to the forefront, as we all believed it would," he said.
Dr. Kornmehl is medical director, Center for Laser Vision Correction, associate clinical professor, Department of Ophthalmology Tufts University School of Medicine, and clinical instructor, Harvard Medical School, Boston.
Steven E. Wilson, MD, professor, chair, and director of refractive surgery, Department of Ophthalmology, University of Washington, Seattle, said a lot of new things are happening regarding excimer lasers. He particularly cited VISX's recent FDA approval for hyperopia. VISX's chief U.S. rival, Summit Technology, also has a bid for hyperopic approval pending.
This approval, along with the surge in LASIK procedures, will expand the market even more, Dr. Kornmehl said.
Approval of two other lasers--by Nidek and Autonomous, which is being acquired by Summit Technology--to treat myopia is imminent, according to Dr. Kornmehl. He speculated that these approvals may lead to a reduction in the cost of excimer laser equipment.

Scanning lasers
In 1998, VISX also introduced an excimer laser model with a laser scan technology; other manufacturers are also working on similar technology.
"The role of these lasers is still undetermined. Preliminary data indicate they have the capacity to produce very smooth ablations," Dr. Wilson noted.
The role of these scanning lasers in conjunction with LASIK is unknown if the laser requires tracking. Once the flap is lifted, he said, the accuracy of the tracking system and the laser's ability to lock onto the pupil may be compromised.
"The answers to these questions and about how scanner lasers will affect LASIK remain to be found," he stated.
He said the event that has had the most impact on him has been the introduction of the Hansatome microkeratome (Bausch & Lomb Surgical).
He said this instrument has reduced the incidence of unexpected complications associated with other instruments.
"We have completed a study that demonstrates that the incidence of flap complications associated with LASIK is markedly reduced when the Hansatome microkeratome is used compared with the automated corneal shaper (Bausch & Lomb Surgical)," Dr. Wilson said.
Another development prominent in refractive surgery is the position of the corneal ring, he added.
"I don't think enough data are available to decide what role, if any, the corneal ring will have relative to excimer laser technology. I have concerns about placement of a foreign body in the cornea and the cosmetic impact of implanting a corneal ring," he said.
"This is an area of intense investigations and it will be interesting to see how this develops," he continued.
Both Drs. Wilson and Kornmehl said they expect further refinement of waterjet technology, in which a LASIK flap would be cut by a stream of water.
"The question here is how reproducibly will this instrument work to make a flap? Discussions indicate that the technology operates smoothly enough that it may be used to make the refractive cut itself instead of using an excimer laser. Right now this is theoretical, but the possibility is there," Dr. Wilson said.
Another thing that Dr. Wilson called exciting is the potential for some existing lasers to cut a LASIK flap.
"I can envision a laser that in one mode can reproducibly cut a flap with no risk of a flap complication. After the flap is lifted, the excimer laser component of the laser performs the refractive ablation," he said. "If we get to that point, the issue of whether PRK or LASIK is better to treat low-level refractive errors may be moot."