March 2013

 

COVER FEATURE

 

Cataract/IOLs, femtosecond cataract

A new twist on femtosecond platforms


by Maxine Lipner EyeWorld Senior Contributing Writer

   
LensAR Laser System

LensAR Laser System Source: LensAR

LenSx Laser LenSx Laser Source: Alcon

Victus System Victus System Source: Bausch + Lomb

OptiMedica Catalys Precision Laser OptiMedica Catalys Precision Laser Source: OptiMedica

Diving into the debate on combined versus dedicated cataract units

Femtosecond lasers have become an accepted part of the LASIK lexicon and now are making inroads into the cataract arena as well, according to Seba Leoni, vice president, global franchise head, cataract, Alcon, Fort Worth, Texas. "Approximately 80% of LASIK procedures in the U.S. are done with a femtosecond laser," he said. Likewise, femtosecond cataract surgery is now on the upswing. In addition to femtosecond units dedicated to cataract use, two out of four of these lasers, the Victus (Bausch + Lomb, Rochester, N.Y.) and the LenSx (Alcon), have regulatory approval to do both LASIK flaps and lens-related procedures using one system. The question is, can these combination units measure up to their cataract-dedicated counterparts?

Scoring the combination entry

Calvin W. Roberts, M.D., chief medical officer, Bausch + Lomb, thinks combination femtosecond systems do have the capability to deliver in both the cataract and the corneal realms. However, he offers a caveat"only if it is a great laser with a great patient interface," he said. To perform a good cataract procedure with a femtosecond laser, he pointed out, you have to be able to get exquisitely good focus on the anterior capsule and within the lens, without any distortions coming from the cornea. "Therefore, the way that you can ideally dock the laser to the cornea for a cataract procedure is to have a fluid interface between the laser and the cornea so that there's no contact to the cornea that could create folds or other distortions," Dr. Roberts said. For femtosecond cataract surgery the Victus uses almost a 100% liquid-filled interface, he said. "[It doesn't] require high vacuum in order to hold it in place because it's not creating distortion," he said. By contrast, to cut a corneal flap, 100% applanation of the interface against the cornea with high suction is needed. "You need no fluid," Dr. Roberts said. "You want the laser right against the cornea because what you need is accuracy down to about 4 microns, and you don't get that if you don't have the laser right against the cornea." Accordingly, the Victus platform offers two settings in one patient interfacea low vacuum, liquid one for cataract procedures, and a high vacuum, sans liquid interface for corneal cutting. Currently in the U.S. the Victus is approved for cutting corneal flaps as well as cataract capsulotomy. In addition, one new application that the Victus just received 510 clearance for in February is the creation of penetrating arcuate incisions in the cornea, something that study results indicate can offer a higher degree of precision.1

Likewise, the LenSx system can do double duty. "The LenSx laser platform was conceived as an image-guided surgical workstation capable of both lens and corneal surgery," Mr. Leoni said. "Surgeons choosing this platform will be able to select either cataract or LASIK flap applications based on the needs of each patient." Once selected the procedure is programmed and executed as it would be with a single-purpose device, he explained.

"Key aspects of the LenSx laser flap creation include enhanced imaging and the use of a curved patient interface," Mr. Leoni said. He is confident that this combination system can deliver an excellent corneal flap while becoming a cataract surgical tool. This can work as long as the original design requirements for the system anticipate both applications, as the LenSx platform does, he explained. He sees some clear advantages to taking the combination tack. "If LASIK and cataract surgery are to be performed in the same venue, a single device may be less expensive for both hardware and service, as well as space considerations," Mr. Leoni said.

Dr. Roberts agreed. "To have two femtosecond lasers, one for refractive and one for cataract, is a lot more money than having a Victus," he said. "Second, in terms of space in a tight ambulatory surgery center, not needing two machines and having everything built in one box is an advantage." This is also true, he thinks, from a service point of view. "The costs are not just upfront, but they are continuous in terms of your service contract and maintenance," he said.

In a competitive cataract-only position

However, Mark J. Forchette, president and CEO, OptiMedica, Sunnyvale, Calif., sees distinct advantages to having a dedicated femtosecond cataract system such as the OptiMedica Catalys Precision Laser. He points to a plethora of elements that can come into play here. "It's the location of the system, the simplicity of its workflow, and the design decisions that we made to optimize the performance for cataract surgery," he said. Mr. Forchette pointed out that targeting the cornea is very different from working deep within the nucleus of the lens. "When we designed our system we did it to treat deeply within the lens, full volume including the safety zone, and we maximized the volume of fragmentation," he said. When you start combining platforms, Mr. Forchette said that there are some inherent design compromises that need to be made. Nick T. Curtis, CEO, LensAR, Orlando, Fla., agreed. "There are tradeoffs," he said. "If you're really efficient in the lens and making accurate corneal incisions, you're going to compromise your flap quality somewhat." He believes that this is the price that the combination systems pay. In his view, with the LensAR Laser System there are no compromises for cataract surgery. "We make a nearly perfect capsulorhexis all the time," Mr. Curtis said. "They're free- floating capsthere are no tags or rough edges or white rim along the edge of the capsulorhexis." Automated software enables surgeons to precisely position the rhexis on the optical axis in the center of the pupil. "The combination systems are manual in surface identification and only look at X and Y axis, not Z, which leads to treatment compromise in capsulotomy and fragmentation involving lens tilt," Mr. Curtis said.

Logistics and efficiency can also play a role. "In many situations the cataract surgery suite is not in the same [location] where they're doing the refractive surgery," Mr. Curtis said. This means either transporting patients or perhaps opting for a compromise location for the unit that is not optimal for cataract or refractive surgery. "LensAR has designed the system with optimal workflow in mind for busy cataract surgeons. In the operating room or a procedure room with our system, surgeons have the ability to deliver care with setup flexibility using the standard gurney," he said.

"We designed our system to be a workhorse in the operating room environment and to do full days of cataract surgery," Mr. Forchette said. "We have some surgeons who have even elected to place our system in the OR and use the integrated patient bed for their surgery." The OptiMedica system has incorporated arcuate femtosecond incisions, something Mr. Forchette views as a natural adjunct of the cataract procedure. With their system, in many cases they have eliminated the need for ultrasound altogether. "This is a rich advancement in the cataract procedure that can occur by looking in that direction versus looking back over our shoulder at flap creation, when a great percentage of practices already have that capability," he said. "So it is not an addition that we feel compelled to make on our system when there's an opportunity to take cataract surgery so much further."

Dr. Roberts disagreed. "I think that we can show that the quality of the LASIK flaps that we get with the Victus are as good as or even better than you can get with a standalone flap maker because our machine is so powerful," he said. Overall, in Dr. Robert's view, the emergence of these combination femtosecond units is another example of how cataract removal is becoming a refractive procedure. "I'm seeing so many of my colleagues who had developed a refractive expertise now embracing cataract with the use of the femtosecond laser because they're bringing that level of precision of refractive surgery to cataract surgery," Dr. Roberts said.

New femto twist article summaryReference

1. Soong HK, Malta JB. Femtosecond lasers in ophthalmology. Am J Ophthalmol. 2009 Feb;147(2):189-197.e2.

Editors' note: The sources have financial interests with their respective companies.

Contact information

Curtis: nick.curtis@lensar.com
Forchette: mforchette@optimedica.com
Leoni: publicrelations@alcon.com
Roberts: calvin.w.roberts@bausch.com

Related articles:

Review of “1-year experience in myopia correction with transepithelial PRK case- matched with femtosecond-assisted LASIK”

Infection following femtosecond AK by Maxine Lipner EyeWorld Senior Contributing Writer

Femto in cataract surgery: The state of the technology by Liz Hillman EyeWorld Staff Writer

Large study to compare conventional phaco to femtosecond laser surgery by Erin L. Boyle EyeWorld Senior Staff Writer

Dissonance in a femtosecond by J.C. Noreika, MD, MBA

An update on billing policy for femtosecond laser use by Ellen Stodola EyeWorld Staff Writer

A new twist on femtosecond platforms A new twist on femtosecond platforms
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