ASCRS news: hinge site may affect dry eye

SAN DIEGO — A new theory on flap orientation and its effects on corneal sensation was one of the big stories to come out of this year’s American Society of Cataract and Refractive Surgery (ASCRS) meeting. A study suggests that using a nasal-hinged LASIK flap, as opposed to a superior-hinged flap, may preserve more corneal sensation and thus prevent symptoms of dry eye for patients after surgery.

Highlights of the ASCRS meeting here included the annual survey of ASCRS membership, which showed this year that LASIK volume is still growing, though not as fast as last year. In some forums, surgeons expressed caution about the promise of customized corneal ablation, while in others promising results with the technique were announced. But the news about LASIK flap orientation seemed to capture the most attention.

Eric Donnenfeld, MD, presented results of a study of 100 patients who underwent bilateral LASIK using the Hansatome microkeratome (Bausch & Lomb) in one eye to make a superior-hinged flap and the Amadeus microkeratome (Allergan) in the other eye to make a nasal-hinged flap.

Dr. Donnenfeld said his theory that flap orientation may affect dry eye was based on the fact that the long posterior corneal nerves, which innervate the cornea, enter the eye at the 3 o’clock and 9 o’clock positions. A superior-hinged flap cuts both arms of this innervation, while a nasal hinge cuts only the temporal arm.

Masked Cochet-Bonnet esthesiometry was performed centrally preoperatively and at 1 and 3 months postoperatively. Results showed that corneal sensation was reduced in all LASIK flaps, but that there was a greater reduction when a superior hinge was used. The loss of sensation was greatest at 1 month, and both eyes had improved by 3 months.

Dr. Donnenfeld pointed out that a nasal-hinged flap did not just improve corneal sensation, but it also helped alleviate the dry eye symptoms often associated with LASIK. Corneal sensation is necessary for normal basal tear secretion.

“It all goes back to a normal feedback loop with a normal corneal sensation. Dryness is sensed. It sends a message to the brain stem, which then stimulates the lacrimal glands to produce tears. With loss of sensation following LASIK, this feedback loop is disrupted, resulting in dry eye,” Dr. Donnenfeld said at the meeting.

Refractive surgery a commodity?

For the second consecutive year, ASCRS focused some of its program on the issues of comanagement and the refractive surgery industry.

During the first Hallway Controversies Symposium of the meeting, five surgeons and a laser vision correction industry insider debated the merits of the business of refractive surgery.

In the first of three debates, J. Charles Casebeer, MD, and Daniel S. Durrie, MD, argued the merits and dangers of offering guarantees to laser vision correction patients. While Dr. Casebeer did his best to be a proponent of offering guarantees, in the end he admitted that the notion of offering guarantees is a tenuous and dangerous proposition. He said promising patients that they can expect 20/20 vision is something no doctor should do, but he did say that promising patients a lifetime guarantee is acceptable, as long as the surgeon is willing to back it up.

Dr. Durrie stuck by his position that no guarantee is a good guarantee. He said he believes that offering promises to patients is the perfect way to confuse patients and, more important, perhaps break the law in many states. He pointed out that advancements in techniques and technology could make meaningless almost any guarantee a doctor could make.

In a second debate, Richard L. Lindstrom, MD, and Jeffrey Machat, MD, delved into the role of optometrists in refractive surgery. Dr. Lindstrom explained that 60% of the laser vision correction market prefers to do without OD comanagement, while the mid-level and “boutique” laser centers need ODs for comanagement reasons. Dr. Machat countered that he believed the use of ODs in the refractive market would only increase over time, as discount laser centers go out of business and other doctors need to bring in ODs to help with their resulting increase in volume.

Finally, in an often exuberant and very direct debate, George Waring III, MD, and former Lasik Vision executive Mike Henderson battled over the issue of whether or not refractive surgery is a commodity. Mr. Henderson, who left Lasik Vision more than a year ago, said that the cost and nature of laser vision correction proved that it was a commodity. While he agreed that doctors were obviously integral to the industry, he said the actual procedure is nothing more than cosmetic and cannot be compared to more serious interventions such as heart surgery.

When Dr. Waring’s turn at the podium came, he ripped off his jacket to reveal a striped vest, placed a hat on his head, grabbed a black cane and began to tout the laser vision correction industry as if he were a sideshow barker, mocking the very industry model for which Mr. Henderson had once worked. Dr. Waring eventually pointed out that while it may be relatively inexpensive, the laser vision correction procedure still requires the social contract between surgeon and patient. He explained that it was not a procedure to be entered into lightly and not something to be traded like gold and pork bellies.

Changing presidents

At the Opening Session, ASCRS officials ushered out the presidency of Douglas Koch, MD, who will stay on as editor of the Journal of Cataract and Refractive Surgery.

Stepping into his shoes will be I. Howard Fine, MD, whom ASCRS Program Director Manus C. Kraff, MD, called the new coach of ASCRS, comparing him to the Zen-influenced head coach of the Los Angeles Lakers, Phil Jackson.

Dr. Fine, who said he attended his first ASCRS meeting 20 years ago, spoke of the constant battle of maintaining fee schedules for cataract surgery. Dr. Fine said that unfortunately government continues to devalue cataract surgery and has cut the fee to half of what it was a few years ago. As Dr. Fine put it to the audience of eye care professionals, “We are victims of our own success.”

Honoring Fyodorov

ASCRS officials and attendees also said a formal and touching farewell to physician and innovator Svyatoslav N. Fyodorov, MD. Probably the best known Russian ophthalmologist, Dr. Fyodorov was killed in a helicopter accident last year. A touching film and his visibly moved daughter, Irina Fyodorov, MD, offered an impressive tribute for Dr. Fyodorov.

On behalf of ASCRS, Dr. Kraff presented Dr. Fyodorov with a portrait of her father, which will hang in the hospital Dr. Fyodorov founded in Moscow.

John C. Cooksey, MD, the only ophthalmologist in Congress, then called on all eye care professionals to become actively involved in health care reform. Dr. Cooksey, who is now serving his third term as a Republican in the U.S. House of Representatives from Louisiana’s 5th District, is striving for various reforms, including good patient protection legislation and antitrust legislation.

Ophthalmology’s hottest developments

One of the biggest events at the ASCRS meeting every year is the Innovator’s Session, and this year was no different. A packed house filling three ballrooms witnessed this year’s best-of-the-best, showing off what could be standard practice in a few years.

Among the several presenters, incoming ASCRS president Dr. Fine discussed his ongoing research into sonic phacoemulsification for cataracts. Dr. Fine believes the fact that sonic forces generate significantly less heat than ultrasound frequencies will protect the eye better during phaco.

A new member of the innovators’ cast was introduced this year as well. Gholam Peyman, MD, presented information regarding the use of telescopic IOLs in low vision patients and his perspective on refractive surgery. Dr. Peyman said he has often considered himself a “closet refractive surgeon.”

ASCRS practice preferences

The growth rate of LASIK procedures declined from 1997 through 2000, according to a survey conducted by David Leaming, MD. From 1997-1998, the growth rate for LASIK procedures was 158%, but this declined to a growth rate of 30% in the 1999-2000 time frame. The estimated annualized volume of LASIK procedures increased from about 170,000 in 1997 to more than 930,000 procedures in 2000.

In a survey of 5,342 ASCRS members, topical anesthetic use for cataract surgery was also noted to be on the rise, with 40% of respondents reporting use of a topical anesthetic with intracameral lidocaine and 24% choosing to use periocular anesthetics. Those figures had changed from from 37% of respondents using topical anesthetics in 1999 and 27% using periocular anesthetics in 1997.

In 1993, an overwhelming majority of respondents (about 75%) made their cataract incisions at 12 o’clock; in 2000, that number had dropped to 26%. Conversely, temporal incisions accounted for just 9% of all incisions in 1993; in 2000 they accounted for 55% of all incisions.

The four-quadrant nucleofractis technique is still the most popular, with about 56% of respondents using that method in 2000. That figure has dropped from 70% in 1996. Clear corneal incisions are also on the rise, with 47% of 2000 respondents using clear corneal incisions vs. only 1.2% using them in 1992.

Also from the survey: most surgeons see their patients three times for postop care, and 36% recommend corrective glasses for their patients at about 4 weeks postop.

The number of surgeons performing radial keratotomy (RK) peaked in 1995, with 45% performing that procedure. On a steady decline since then, only 7% of surgeons performed RK in 2000.

Hyperopes in the +1 D to +3 D range are overwhelmingly recommended for LASIK surgery. At the +5 range, more than half the surgeons would recommend the patient wait before having any kind of surgery.

Most surgeons (60%) plan to increase the amount of LASIK surgery they currently perform. Of those surgeons not performing phakic IOL implantation, 70% plan on performing it in the future. More than half the respondents do not currently perform laser thermal keratoplasty surgery, but plan on performing it in the future.

The top three types of courses surgeons have taken in 2000 include courses on RK, photorefractive keratectomy (PRK) and LASIK. More than half the respondents are not interested in training in the use of KeraVision Intacs, according to the study.

In 1999, 43% of survey respondents comanaged cataract patients and 42% comanaged LASIK patients. In 2000, 42% comanaged cataract patients and 36% comanaged LASIK patients.

The top three things respondents would change in their offices: add space (19%), improve personnel quality (10%) and improve efficiency, obtain better scheduling and electronic medical records (7% each).

For a detailed look at the survey, visit http://www.analeyz.com.

Wavefront still down the road

At the 2000 ASCRS meeting, wavefront was the buzzword intriguing surgeons and promising that soon laser vision correction would be lowering the bar from 20/20 to 20/10 and perhaps further. However, 1 year later, the presentations at ASCRS seemed to be promoting a more cautious look at the use of wavefront.

Jack Holladay, MD, presented less than 1-month-old data of a recent enhancement he performed using custom ablation. While he achieved very good results, Dr. Holladay said the results made him much less optimistic about custom ablation re-treatments under a LASIK flap. He thinks re-treatments may be better served with the use of PRK.

Echoing Dr. Holladay’s concern regarding the abilities of custom ablation in certain circumstances, Manus Kraff, MD, warned that wavefront still has a long way to go. He explained that surgeons still need to learn how best to read the maps created by wavefront analysis, and they also need to learn exactly what higher-order aberrations mean to total visual acuity.

Dr. Kraff noted that his own experience showed that while non-wavefront-based surgery may increase higher-order aberrations, the visual outcomes improve anyway.

While caution seemed to be the tone of most presentations, there was news of the progress of customized ablation. D. Keith Williams, MD, presented information regarding his five-patient study using the Visx S3 ActiveTrak system and the Visx PreVue lens system.

Dr. Williams enrolled five patients who had undergone previous LASIK surgery with poor results, including low visual acuity and ghosting. Using Visx’s WavePrint system, he fashioned PreVue lenses that corrected the deficits of the previous surgery and adjusted for the patients’ higher-order aberrations. If after testing the PreVue lenses the patients noticed a significant improvement, then they were re-treated using the same parameters that were used to make the PreVue lenses.

The results were excellent, Dr. Williams said. All five patients made remarkable improvements, he said, although only three of the five improved beyond 20/30 UCVA.

Surgeons interests more clinical

An all-star team of international refractive surgeons gathered at ASCRS to debate the merits of the laser vision correction industry worldwide.

The consensus for the surgeons, including James Hays, MD; Daniele Aron-Rosa, MD; Frank Goes, MD; and Hideharu Fukasaku, MD, was that while North American ophthalmologists are involved in several non-medical controversies in the field of refractive surgery — such as the competition between discount and high-end LASIK centers and the fight between MDs and ODs on the comanagement battlefield — the rest of the world is not nearly so affected by issues outside medicine.

In another round of questioning the necessity of optometric comanagement, Leon Solomon, MD, presented his argument that there was no “good” comanagement.

He asked the audience, “What has happened to the neighborhood ophthalmologist?” He said patients still prefer to be treated “the old fashioned way,” by one doctor.

Cataracts affect intelligence

Study data presented here indicated that cataracts may affect a patient’s mental efficiency in processing information. Siegried Lehrl, PhD, and Kristian Gerstmeyer, MD, of the General Hospital in Minden, Germany, have found that sensory intelligence decreases with the onset of cataracts.

The decrease of intellectual capacity produces susceptibility to depression and, consequently, a risk factor for mortality. As a result of the initial data, a formal clinical study will be initiated.

Refractive outcome with Array

The IOLMaster calculates a more accurate refraction and is equivalent to A-scan in measurement of axial length and calculation of multifocal IOL power, according to data presented here by H. Burkhard Dick, MD, of Mainz, Germany.

Deviation from target refraction was compared in 79 eyes of 53 patients, of which 43 underwent ultrasound and 36 were measured via IOLMaster for implantation of the Array multifocal IOL (Allergan). Eyes measured using ultrasound were slightly myopic. Eyes measured with the IOLMaster were slightly hyperopic, a more favorable refraction, according to Dr. Dick.

ICL safe, efficacious for myopia

Early results of an ongoing Food and Drug Administration clinical trial suggest that STAAR Surgical’s ICL phakic posterior chamber lens is a safe and effective surgical treatment for patients with myopia.

As part of the trial, 579 eyes of 335 myopic patients were implanted with the ICL. All patients had had spherical equivalent ranging from –3 D to –23.5 D, with less than 2.5 D of astigmatism. The mean preoperative spherical equivalent was –10.1 D.

At least 80% of treated eyes achieved an uncorrected visual acuity of 20/40 or better at 1 week or more after surgery, according to John A. Vukich, MD, who presented the results here. At least 77% of cases are within 1 D of emmetropia at 1 week through 12 months. At all postoperative visits, at least 97% of eyes were within 1 line of their preoperative level, with between 9% and 13% of eyes experiencing improvements in best corrected visual acuity (BCVA) of two lines or more.

According to Dr. Vukich, 12-month data showed excellent predictability of 72% ±1 D, efficacy of 20/40 or better in 89% of patients, rapid return of BCVA and a low incidence of lens opacities and rises in intraocular pressure (IOP).

According to Dr. Vukich, there were no surgical complications; however, one eye lost 5 lines of BCVA due to macular degeneration. This incidence was unrelated to the ICL, Dr. Vukich said.

Two ICLs needed to be removed due to an increase in IOP. Adverse events included the removals or replacements of seven ICLs due to sizing issues. The adverse events have been correctable, according to Dr. Vukich.

LASEK vs. LASIK

Two studies presented at the ASCRS meeting showed that laser epithelial keratomileusis (LASEK) was just as effective as LASIK.

Daniel Durrie, MD, and Patrick Condon, MD, presented two separate studies showing that, although the LASEK procedure lacks the “wow” factor of LASIK, its 1-month and 3-month results are equal to the keratome-based laser surgery.

Microkeratome papers

Use of the Summit Krumeich-Barraquer Microkeratome (SKBM) in a pre-assembled one-piece mode is safe, according to Elias Zaidman, MD.

Although using the SKBM in this fashion is not what the manufacturer (Alcon) instructs, Dr. Zaidman said there were no postop complications, no incomplete flaps, no decentered flaps and no loss of suction during the pass in a study of 250 consecutive eyes.

The Flapmaker Disposable Microkeratome by Refractive Technologies offers safety and reliability, yet its safety profile could be improved by changing the rotational cable mechanism, according to a study presented by Rupal Shah, MD. A retrospective study was done on a series of 500 consecutive eyes. The overall complication rate was 2.2%. Complications included four free caps, one buttonhole, two passes without cutting and one case of epithelial ingrowth. There were no cases of diffuse lamellar keratitis or infection, Dr. Shah said.

“Most of the complications occurred when the rotational cable was worn out due to friction with the lock nut,” she said.

Dr. Shah said this is the “only popular” disposable microkeratome. “Our low complication rate could be further improved by changing the rotational cable mechanism,” she said.