ASCRS Symposium
News & Notes from the ASCRS Symposium

ASCRS launches LASIK patient education initiative
To help patients make informed decisions about undergoing LASIK, the American Society of Cataract and Refractive Surgery launched the Eye Surgery Education Council (ESEC). The goals of the initiative are to provide patients with accurate, accessible information about laser eye surgery and to promote physician/patient dialogue about the benefits and risks.

The Council has developed LASIK screening guidelines for patients. The guidelines describe who is an ideal, less than ideal and a noncandidate for the procedure. They also explain the importance of realistic expectations, and provide questions patients should ask their surgeons and information on what types of screening tests they should expect.

The Council has also developed a brochure and a Web site for consumers. Patients seeking more information about LASIK can call (800) 536-ESEC or visit www.eyesurgeryeducation.com.

The ESEC Medical Advisory Board noted a recent Harris Interactive poll that revealed widespread misconceptions about LASIK among the public. For example:

• 41% of respondents believe that anyone with imperfect vision is an ideal candidate for laser eye surgery.
• 31% don't realize that a medical degree is necessary to perform LASIK.
• Many consumers considering LASIK lack an understanding of its risks and benefits: 62% are hesitant to have the surgery for fear of complications, but 37% expect the surgery to result in perfect vision.

Roger Steinert, M.D., chairman of the ESEC Medical Advisory Board, said the council's initial efforts are focused on LASIK because it's the procedure patients currently consider first, but efforts will evolve to fit the needs of the public and to address changes in eye surgery technology.

The ESEC was made possible by unrestricted educational grants from Alcon Laboratories, Bausch & Lomb, VISX, TLC Laser Eye Centers, IntraLase, Nidek, Moria, Vision Fee Plan, Refractec and Katena Products.

Refresh Endura, the first eye drop that supplements both the water and oil components of the eye, works in three main steps.

A new kind of artificial tear

For dry eye patients who haven't found relief using conventional artificial tears, Allergan introduced Refresh Endura, a lubricant eye drop that treats all three layers of the tear film.

Refresh Endura is a stable oil-in-water emulsion, which simultaneously delivers oil to the lipid layer, water to the aqueous layer and gel to the mucin layer.

Allergan said that in clinical studies, patients who used Refresh Endura an average of two to three times daily experienced significant improvement in their persistent dry eye symptoms, whether their symptoms were mild/moderate or moderate/severe. The company also said patients reported the drop to be well-tolerated, with no significant blurring or clouding of vision.

The drop is milky white on instillation, but dissipates into clear components. It hasn't been studied in contact lens-wearers, who are therefore advised to instill the drop prior to lens insertion or after lens removal. Also, Allergan said that the type of oil in the drops doesn't clog pores on skin, so the drops aren't contraindicated for patients with blepharitis.

Jay Pepose, M.D., Ph.D., director of PeposeVision Institute and clinical professor of ophthalmology at Washington University, presented the 6-month results of a multicenter trial of scleral expansion to treat presbyopia. In the prospective, nonrandomized, unmasked study, surgeons operated on the dominant eye of 29 emmetropic presbyopic patients ages 50 to 60.

The study was designed to determine whether scleral expansion patients regained near vision and to assess the safety of the procedure. However, it was not designed to test the underlying mechanism(s) by which this might occur, whether by classical or alternative forms of accommodation or pseudoaccommodation. By convention, the term accommodative amplitude was used in reporting the results.

The technique was a modification of the original scleral expansion surgeries; separate injection-molded PMMA segments, 5.5 mm by 138 microns and 925 microns in height, were placed in scleral pockets in each of the four oblique quadrants of the eye. Mannitol was given at the end of the procedure.

Accommodative amplitudes were assessed using a push technique to measure a near point from a 70-cm and a 30-cm reference point. At some testing sites, patients were also assessed with dynamic videoretinoscopy, infrared power refractometry and Hartmann-Shack aberrometry. These objective assessments correlated with the push measurements, Dr. Pepose said.

Key results at 6 months:

• There was a statistically significant mean increase in accommodative amplitude of the operated eyes between 1.5 and 1.7D.
• 59% of the operated eyes had a greater than +1.25D increase in accommodative amplitude. Corresponding median near visual acuities at 40, 30 and 20 cm improved by approximately 3 lines in the operated eyes.
• All operated eyes showed self-limited subconjunctival hemorrhages; there were no cases of anterior-segment ischemia, angle closure or loss of best-corrected vision.
• 4 high responders, who showed greater than a 4D increase in accommodative amplitude, and 4 nonresponders, who had minimal or no improvement, were identified.

Dr. Pepose said further studies are needed to determine whether the differences are a reflection of surgical technique or variations in scleral thickness or location of the ciliary body or zonular apparatus in individual patients.

Interestingly, a lower increase in accommodative amplitude was seen in the control eyes. Dr. Pepose said accommodation is a consensual response, and further studies are needed to determine whether that effect on the control eyes is due to a central neural feedback mechanism or whether it represents artifacts from current testing techniques.

On a post-op questionnaire, 69% of patients reported that they could read a newspaper unaided; 63% could read a menu unaided; 69% could work on a computer unaided; and 73% could shave and apply makeup with glasses. Those results compare favorably with satisfaction surveys from patients who have surgical or contact-lens-induced monovision, Dr. Pepose said.

Most recent advances in scleral expansion surgery include the use of a motorized instrument, the Presby Drive, to facilitate the creation of scleral pockets uniform in depth, and the use of high-frequency ultrasound to better delineate the location of the ciliary body to optimize quadrantic placement of the scleral expansion bands.

Companies approve merger

A large majority of Asclepion-Meditec AG shareholders approved the company's merger with Carl Zeiss Ophthalmic Systems, AG.

The new company, to be called Carl Zeiss Meditec AG, will be able to offer a complete range of products from diagnosis and treatment to follow-up for all pathologies of the eye.

The merger is expected to take effect this month at the earliest.

Microkeratome re-debuts

Paradigm Medical Industries officially entered the refractive surgery market with the launch of its K-Tome microkeratome, which was acquired along with Innovative Optics earlier this year.

The K-Tome blade is software-driven through a patented mechanical process, which eliminates potential problems with gear-driven instruments, such as corneal tears and free flaps.

A single, flexible cable drives the K-Tome.

J. Charles Casebeer, M.D., Larry Hicks, the former president of Innovative Optics, and Igor Gradov, co-developer of the K-tome, will assist Paradigm with further development of the instrument. Dr. Casebeer said a significant advantage of the K-Tome is that the surgeon can view the cut at every step of its creation through the sapphire applanator, and abort if he or she sees fit.

Paradigm Chairman and CEO Thomas Motter said that the K-Tome offers surgeons "a more elegant approach, enhanced safety features and a significant reduction in blade price." The dimensions of the sterile blades (100 microns thick and 1 mm wide), developed by Paradigm, help to ensure a clean, smooth cut.

Automatic iris image registration and tracking explored

VISX, Inc. is currently testing and validating its next generation of LASIK eye-tracking technology, which uses images of the iris to align preoperative diagnostic and laser iris images and intraoperatively track eye cyclotorsion.

Carol Harner, Ph.D., vice president for Research and Development, explained how the registration technology works.

Using iris images obtained from the WaveScan diagnostic unit and the Star S3 laser, it automatically:

• "unwraps" the iris in both images
• selects reference points
• finds multiple matching reference points for each iris section
• calculates the torsional angle from multiple measurements (See image below)
• uses special algorithms to calculate the ablation torsion angle.

Cyclotorsional movements are then tracked intraoperatively using similar technology. This potentially tighter alignment of the laser ablation to eye rotation is achieved without ink markings on the sclera, which are time sensitive and prone to human error.

Also at the meeting, VISX announced:

Its first hyperopia wavefront results. W. Bruce Jackson, M.D., from the University of Ottawa Eye Institute, and his study group operated on 12 eyes of 6 patients with a mean age of 52.8, hyperopia up to +3D and astigmatism up to +1.5D. In the prospective, nonrandomized study, no nomogram adjustments were made; all eyes were targeted for emmetropia; and optical zones were blended to 9 mm.

After the WaveScan-guided treatments using the Star S3 with ActiveTrak:

• All patients had 20/20 or better UCVA at 1 month.
• 33% had 20/16 UCVA at 1 month.
• There was a mean change in MRSE of ­0.02D from 1 week to 1 month.
• 92% of eyes were within + 0.50D of target at 1 month.
• No eyes lost two or more lines of BSCVA.

	VISX is studying whether automatic cyclotorsional registration and tracking based on iris images, which are unique to each patient, will result in better LASIK results. A patent on the technology is pending.

Additional technology news. The company, which has begun studies of a laser treatment for presbyopia, signed an exclusive worldwide license agreement for a portfolio of patents held by Luis Ruiz, M.D., relating to the treatment of presbyopia with multifocal ablations. The company also signed a Letter of Intent with Tracey Technologies for exclusive global rights to Tracey's ray-tracing technology for use in customized LASIK treatments. A spokesperson said the technology will not be a replacement for the Hartmann-Shack-driven WaveScan, but it increases the number of patients whose wavefront aberrations can be measured.

And . . .

• The Volk Incision Viewing Instrument (IVI) will be available soon. It's designed to allow visualization of clear-cornea incisions as they're being made, as well as visualization of the internal opening at the trabeculectomy site, phakic and aphakic implants, and anterior chamber lens implant position.
• CIBA Vision Surgical has obtained exclusive licensing, marketing and distribution rights to Dr. Ioannis Pallikaris' subepithelial separator (SEB). The SEB is a microkeratome-based device with a suction ring that creates an epithelial flap for subepithelial LASIK, eliminating the need for alcohol to separate the epithelium from the basement membrane.
• Nidek, Inc. submitted a supplemental application to the FDA for approval of its Windows-based operating system and a new intraoperative eye-tracking device for the EC-5000 laser, key elements of Nidek's custom ablation system. The four-beam infrared tracker monitors the position of the undilated pupil.
  In addition, Nidek received FDA 510(K) clearance for its NM-1000 Digital Non-Mydriatic Fundus camera and its US-1800 Echoscan ultrasonic biometry instrument.
• A Paul Dougherty, M.D., presented the results of his study that compared LASIK performed on 135 eyes with a "thin-flap," 130-micron microkeratome head (Becton-Dickinson K-3000) with LASIK performed on 237 eyes with a 160-micron microkeratome head. No flap complications occurred in the "thin-flap" group.
  Dr. Dougherty concluded that "thin-flap" LASIK is safe and effective for patients with high myopia and/or thin corneas, but advised against LASIK for any patient whose cornea is thinner than 500 microns.
• A The FDA accepted Bausch & Lomb's modular premarket approval application for the Zyoptix custom ablation system. The company said it anticipates U.S. availability in early 2003.
  B&L also introduced the new Zyoptix Diagnostic Workstation, which combines the Orbscan IIz and the Zywave II. The Orbscan IIz includes hardware and software upgrades that deliver an immediate picture of essential surgical-planning data points.