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Refractive Surgery | Apr 2011

Femosecond Lasers for Cataract Sugery: When Will Laser Cataract Surgery Be a Routine Procedure?

Only a few surgeons have experience using femtosecond lasers for cataract surgery.

Femtosecond lasers have undoubtedly made their grand entrance into the field of cataract surgery. Practitioners seem enamored with the potential for this technology to revolutionize cataract surgery by perfecting some of the most difficult parts of the procedure, including the capsulorrhexis, nuclear fragmentation, and incision creation. The potential for laser cataract surgery to dominate the marketplace is undeniable; however, it is likely that any drastic changes to routine surgical technique will take several years. Only a short list of surgeons has experience with this potential procedural phenomenon—and even a shorter list perform it in their own practices. CRST Europe has covered the development of laser cataract surgery extensively. We have provided background into how the procedure works, and we have reported on the regulatory status and the clinical evidence for three available platforms: the Catalys Precision Laser System (OptiMedica Corp., Santa Clara, California); the LensAR Laser System (LensAR, Inc., Winter Park, Florida); and the LenSx Laser System (Alcon Laboratories, Inc., Fort Worth, Texas). Since the time of our last report, another player has entered the laser cataract surgery market. Now Technolas Perfect Vision GmbH (Munich, Germany) has introduced the Customlens cataract surgery procedure, performed with its Technolas Femtosecond Workstation, which is reportedly the only femtosecond platform capable of both cataract and refractive techniques. For a recap on the Catalys, the LensAR, and the LenSx and an introduction to Customlens, see Four Laser Cataract Surgery Technologies.

Rather than once again report on the perceived benefits and surgical considerations for laser cataract surgery, the purpose of this article is to discuss some of the more practical considerations for its use, including practice models, financial aspects and pricing strategies, and the coming availability of this technology for widespread commercial use.

COMMERCIAL USE

In the United States, Stephen G. Slade, MD, is the only surgeon who has performed laser cataract surgery in a commercial, office-based setting with US Food and Drug Administration (FDA) approval. He practices at Slade and Baker Vision in Houston.

“We have had the LenSx femtosecond laser since February 2010, and it is fully approved through the FDA,” Dr. Slade told CRST Europe in a telephone interview. “We use it on the great majority of our patients and virtually all of our premium IOL patients.”

Dr. Slade has performed several hundred procedures with aid of the LenSx femtosecond laser. He charges more when the patient selects laser cataract surgery and receives a premium IOL or has his or her astigmatism corrected with the laser. Because cataract surgery is covered by government insurance (Medicare) and not paid out of pocket, he cannot charge extra if the patient undergoes laser cataract surgery alone. Dr. Slade mentioned that he is able to increase the fee for premium IOLs in patients who select laser cataract surgery.

The femtosecond laser is located near the pre- and postoperative areas of Dr. Slade’s practice. The patient is moved between rooms on a motorized surgical gurney (USFK, Düsseldorf, Germany), first to the preoperative room to undergo the following steps with the femtosecond laser: incision creation, capsulotomy, and the break-up of the nucleus. If the patient has astigmatism and has agreed to pay the additional charge, Dr. Slade also uses the femtosecond laser at this time to create arcuate limbal incisions. The patient is then wheeled into the operating room, where the rest of the procedure is carried out, including phacoemulsification of the remaining nucleus and IOL implantation.

“What this technology allows me to do is soften the nucleus so that I can take much of it out with irrigation and aspiration alone,” Dr. Slade said, adding that patient satisfaction in his practice has been tremendous. “I am starting to see a large patient demand and a large patient preference for laser cataract surgery.”

Zoltan Nagy, MD, has also experienced patients’ demand for laser cataract surgery in his practice in Budapest, Hungary. He is the only surgeon in Europe to use this procedure routinely at his own center; however, his surgeries have been part of a clinical study and therefore he has not been able to charge an additional fee. He has asked patients if they would be willing to pay out of pocket for laser cataract surgery and the answer, he said, has almost always been yes.

“I have performed about 350 cases with femtolaser refractive lens surgery,” Dr. Nagy said in an e-mail interview with CRST Europe. “I perform femtolaser surgery usually on Tuesdays and Wednesdays. It is useful for refractive lens exchange and for cataract up to grade 3.5.”

Dr. Nagy uses the femtosecond laser for the capsulorrhexis, lens fragmentation in cataract patients or lysis of the lens in refractive lens exchange patients, and creation of corneal wounds including the main and sideport incisions. These steps take approximately 30 to 60 seconds, and the entire surgery lasts approximately 5 minutes. Dr. Nagy uses the femtosecond laser in a separate operating room, performing two to three laser procedures before he moves patients to separate operating rooms to undergo phacoemulsification.

“The corneal incision is self-sealing, so you can wait even hours before starting phacoemulsification,” Dr. Nagy explained.

At the European Society of Cataract and Refractive Surgeons (ESCRS) Winter Meeting in Istanbul, Turkey, Dr. Nagy shared his most recent experience with laser cataract surgery. He compared results in 40 eyes (40 patients) that had undergone either conventional cataract surgery with ultrasound phacoemulsification (n=20) or laser cataract surgery (n=20).1 In the laser cataract surgery eyes, the risk of postoperative cystoid macular edema was lower than in the conventional surgery eyes, he said.Even with these and other surgical benefits, laser cataract surgery continues to be performed by only a small number of surgeons—specifically those who are working with companies to bring these products to market. Dr. Nagy said that more surgeons will have access to the procedure in due time.

“I think laser cataract surgery will spread quickly. It is hard to say how long it will take—I think a couple of years can be predicted, as it happened in femtolaser LASIK cuts,” Dr. Nagy said.

PRELIMINARY EXPERIENCE

Drs. Slade and Nagy are lucky enough to have the equipment to perform laser cataract surgery at their own centers, but most others have used these lasers only in animal models or as part of clinical trials. In these cases, travel to other centers is required, with the surgeon returning to his or her own center to once again practice conventional cataract surgery. Michael C. Knorz, MD, recently traveled from Germany to Budapest to perform laser cataract surgery with Dr. Nagy at Semmelweis University.

“What was most impressive was a perfect capsulorrhexis in every single case,” he said in an e-mail interview with CRST Europe. “But every case felt easier than nonlaser cataract surgery because the incisions were already there, because the capsulorrhexis was perfect, and because the nucleus was either prechopped or liquefied.”

Professor Knorz hopes to have the LenSx laser installed at the University Medical Centre Mannheim later this year. He plans to leave the laser inside the operating room so that he can use its built-in optical coherence tomographer (OCT) to measure the eye, select the desired diameter and position of the capsulorrhexis, locate the area of nucleus liquefaction, and make the corneal incisions right inside the operating room. After these steps are carried out with the femtosecond laser, Professor Knorz and his medical team will complete lens removal with conventional methods.

“A prechopped or liquefied lens requires little or no phaco power, which is better on the corneal endothelium and safer for the eye because there is less risk for posterior capsular rupture,” Professor Knorz said, adding that he plans to begin with laser cataract surgery only in patients who elect implantation of a premium IOL. “The upcharge will be about €1,000 per eye, depending on the final price for the unit and the disposables,” he said.

Professor Knorz will likely be among the first surgeons in Europe to own a femtosecond laser for cataract surgery, and he acknowledged that adoption of this technology in routine clinical practice might differ depending on the market.

“In a market where patients are used to paying extra for their surgery, it will be easier to adopt this technology,” he said. “Patients undergoing premium IOL implantation benefit most, because all premium IOLs require a perfect capsulorrhexis, and most of these patients have a rather early cataract or no cataract at all, meaning their lens is softer and can be liquefied by the LenSx laser.”

William J. Fishkind, MD, FACS, traveled from his surgical center in Tuscon, Arizona to Mexico City, where he performed 14 procedures with the LensAR Laser System approximately 16 months ago. Like Professor Knorz, Dr. Fishkind had nothing but rave reviews for this technology. Their only difference in opinion is that Dr. Fishkind believes, in due course, that laser cataract surgery will be used not only in premium IOL patients but in all patients undergoing cataract surgery.

The time frame for getting to this point? It is hard to predict, Dr. Fishkind said.

“If I had to give an approximate date based on a number of factors, including FDA approvals, I would say at least 5 years. Given the limits in production, the small number of companies, and the expense of creating and mobilizing the machines, I think we can expect the innovators to talk about laser cataract surgery for the next 1.5 years, and the earliest we will hear others starting to think about laser cataract surgery is another 1.5 to 3 years,” he said. “It will take a solid 5 years for the revolution to occur.”

During his experience in Mexico City, Dr. Fishkind used a prototype of the LensAR Laser System that differs from what will eventually be available to surgeons commercially. For instance, Dr. Fishkind said, the docking system “wasn’t nearly as sophisticated as it is now. But given this fact, the procedure was still impressive.”

Dr. Fishkind strictly performed only capsulorrhexis and laser lens fragmentation with the femtosecond laser. He explained that, after the laser was docked and aligned, he would perform the laser lens ablation, starting deep in the tissue, and then proceed to the capsulorrhexis. When these steps were complete, the laser would turn off.

Once the LensAR platform is commercially available, more femtosecond-laser–assisted steps will be possible, he said. First, the device will analyze corneal curvature and identify the visual axis so that the capsulorrhexis can later be centered over the visual axis. Second, the nuclear fragmentation will be performed based upon a programmed algorithm. Dr. Fishkind explained that an algorithm that produces pie-shaped fragments works better for a hard nucleus, and one that produces spherical-based fragments works better for a soft nucleus. Third, the capsulorrhexis will be made over the visual axis, followed by the paracentesis, the main incision, and, if desired, limbal relaxing incisions (LRIs).

“I used both spherical- and cubical-shaped algorithms, and I did what we call French fries, which is another algorithm for nuclear fragmentation,” Dr. Fishkind said. “Those fragments were large enough that I still needed to use ultrasonic energy to remove the fragments. What I was left with was a clean capsular bag or a nuclear plate that I then removed anteriorly with phaco.”

With softer nuclei, Dr. Fishkind was able to aspirate the nucleus with the phaco tip. “What I foresee is some kind of phaco I/A tip,” he said. “It would be an ultrasonic I/A tip that would remove these fragments.”

In Mexico City, the femtosecond laser was stationed in one room, and the remaining surgical steps were carried out in another. This could be a typical set-up in the future for multisuite, high-volume practices, Dr. Fishkind said.

“Basically one laser fed two dedicated operating rooms,” he said of the set-up in Mexico City. The practice model for multisuite centers will follow the same process. “Once you do the procedure with the femtosecond laser, that patient is moved to the operating room and prepped and draped. At the same time, another patient is undergoing the laser portion of the procedure in the other room. This process will speed up the surgical time and allow more patients to be done in a high-volume practice.”

A second set-up could be used by moderate-volume surgeons with one surgical suite. In this arrangement, the surgeon would perform laser cataract surgery in two steps, completing the femtosecond laser portions outside of the operating room before the patient is wheeled into the operating room. If more than one surgeon practices at the center, one could perform the laser portion and the other the cataract extraction. This, Dr. Fishkind said, will also facilitate a faster surgical process.

A third set-up, for the outpatient setting, would be the least likely scenario for use of laser cataract surgery due to cost constraints of a small practice. “If the surgeon invests in this technology, they will get the benefit of a safer surgery,” Dr. Fishkind said, adding that if expansion is possible, practices should consider femtosecond laser placement in their physical plan when designing the larger practice.

“My personal opinion is that [laser cataract surgery] is going to change the way we do things, and it is going to make the removal of the nucleus safer and faster,” he said. “Laser cataract surgery is going to decrease the amount of trauma that is inherent in phacoemulsification. It is going to make the capsulorrhexis sit right where you want it. That has been elusive.”

CHARGING FOR LASER SURGERY

Right now, Dr. Slade is the only practitioner able to charge extra for laser cataract surgery. The financial burden rests with the patient, as currently there is no reimbursement for the procedure by the US Centers for Medicare and Medicaid Services (CMS).

“Reimbursement is an issue that is still unclear,” Dr. Fishkind said. “However, the theory is that if there is a patient who is already going to spend $1,000 to $2,000 for a toric or multifocal lens, they would be willing to spend an extra $1,000, for example, for the laser treatment. I think there may be some truth to that.”

In the March issue of CRST Europe’s sister US publication, Shareef Mahdavi discussed the results of a recent survey of 53 cataract and refractive surgeons who plan to adopt the femtosecond laser for cataract surgery once it becomes commercially available (Figure 1).2

“Opinions vary widely among surgeons as to how many of their patients will also choose (and pay for) use of the laser,” Mr. Mahdavi wrote. “Further analysis of survey data shows that surgeons predict that approximately 30% of their cataract patients will also have their procedure performed with a laser.”

PATIENT EXPERIENCE

Surgeons who effectively educate their patients on laser cataract surgery and the options available to them will be the surgeons most likely to succeed, Mr. Mahdavi said. “This will continue to hold true as long as doctors collect fees directly from patients, because the doctor-patient relationship is also one of doctor-consumer,” he said.

William W. Culbertson, MD, had an interesting experience with one patient who was so impressed with her results after laser cataract surgery in one eye that she tried to reenter the feasibility study for the Catalys system, held at the Centro Laser in Santo Domingo, Dominican Republic, to have her other eye treated. “Of many milestones, [this] one stands out as the time I knew this technology would make a major difference in the lives of cataract patients,” he wrote in an article in our sister publication.3 “I look forward to the day … when millions of cataract patients, with the same enthusiasm, will realize the benefits of better uncorrected vision after cataract surgery.”

Dr. Culbertson continues to travel to Centro Laser in Santo Domingo to perform laser cataract surgery with the Catalys cataract system. He has performed more than 100 procedures on these trips and has used the laser for every part of the cataract procedure, including anterior capsulotomy, lens fragmentation and softening, cataract incisions, and corneal relaxing incisions.

“It has been called femtosecond-assisted cataract surgery, but I think it is more of a cataract pretreatment,” Dr. Culbertson said in a telephone interview with CRST Europe. “It is preconditioning of the eye for cataract surgery. You still have to enter the eye through the incision, you still have to remove the capsule, you still have to aspirate and/or phacoemulsify the lens nucleus and cortex, and you still have to put the IOL in the eye. It hasn’t saved you any steps—you still perform all the fundamental parts of cataract surgery. It just makes the procedure safer and more predictable.”

SURGICAL BENEFITS

Whether or not surgeons can charge for laser cataract surgery, patients are already being treated with this technology, and the surgeons we interviewed reported observing benefits of the technology.

“Laser cataract surgery offers so [many] safety and efficacy advantages to the patients,” Dr. Slade said. “These patients are seeing better and sooner than after conventional cataract surgery.”

Dr. Fishkind agreed. “Having a rhexis that is perfectly round and centered is more than an academic interest,” he said, adding that Warren Hill, MD, has presented data showing that a consistently round and centered capsulorrhexis improves the relationship between the implant and the capsular bag.4-7 “The implant sits in a more stable position, and you can be more accurate when you determine implant power.”

Gerd U. Auffarth, MD, who has experience with the Technolas Customlens procedure, also highlighted surgical benefits of laser cataract surgery during a discussion at the ESCRS meeting in Istanbul.8 The Customlens platform, which can be used for capsulorrhexis creation, lens fragmentation, incisions, LRIs, and arcuate incisions, should be available in the second half of 2011, according to Technolas Perfect Vision.

“The femtosecond laser will enhance cataract surgery in both simple and difficult cases,” he said during the ESCRS meeting.

Professor Auffarth presented results from the first human clinical evaluation of 15 patients who underwent laser cataract surgery with Customlens. He said that, although he used a prototype of the laser, the Customlens procedure featured a safe and efficient cutting process for capsulotomy and that lens fragmentation was achieved with circular and radial cuts, the latter of which were the most efficient. Professor Auffarth conducted the procedures in conjunction with Luis Ruiz, MD, in Columbia. Gas bubble hydrodissection occurred after the internal fragmentation, Professor Auffarth explained, adding that there are clear benefits to prefragmenting the lens into nuclear segments with the femtosecond laser.

Kasu Prasad Reddy, MD, has also performed laser cataract surgery with the Customlens platform for the past 5 months. Dr. Reddy practices at Maxivision Eye Hospital in India, where the laser is positioned in one operating room and the procedure is finished in another room.

“I find that manual rhexis is difficult in intumescent cataracts, even for the experienced surgeon like myself who has done thousands of these cases. But with the laser, capsulorrhexis is much easier,” Dr. Reddy said in a telephone interview with CRST Europe. He added that use of the femtosecond laser for capsulorrhexis creation is most beneficial in harder nuclei.

Cracking the nucleus is also easier when the femtosecond laser is used in harder cataracts, he said. “It makes your phaco technique easier, and the corneas look crystal-clear afterward.”

Although Dr. Reddy is not sure how the fees for laser cataract surgery will be structured when the time is right, he is convinced that patients will have no problem paying the additional cost. “Just like our competitors, we will also offer [LRIs] and, of course, the incisions for phacoemulsification,” he said. “In the end, this is a prime-time procedure, and we as a practice think that the patient is willing to pay this extra amount of money to receive laser instead of manual treatment.”

DEVELOPMENT

Femtosecond laser cataract surgery did not just develop overnight. The idea was contrived long before most surgeons had even considered the femtosecond laser a viable technology for cataract surgery. During his telephone interview with CRST Europe, Dr. Culbertson was reminiscent of the different iterations of the Catalys platform since his involvement began 5 years ago.

“This project began in Santa Clara, California, in OptiMedica’s facility,” he said. “Our first efforts were based on laboratory research, and we found that the procedure did work as we planned. Yet we knew that we needed to refine some things.”

For starters, the platform initially had a fixed curved patient interface (Figure 2) that seemed to work in laboratory models but did not always properly attach to the human eye. In some cases, deep corneal folds were created during suction attachment, deflecting the laser light and producing uncut areas in the capsule.

“We put a stop on everything and spent months creating an immersion lens attachment of the laser to the cornea. There is now a liquid interface in between the imaging lens and the cornea,” Dr. Culbertson said. “Now the cornea remains undisturbed and undistorted. Also, we no longer have problems getting the curved contact lens into the space between the lids.”

This Liquid Optics Interface (Figure 3) allows the surgeon to precisely image the anatomy of the eye and creates perfect focus of the laser, executing a complete 360° capsulorrhexis. The LensAR laser system also uses a liquid interface.

“This change made a huge difference, and we are quite proud of our effort,” Dr. Culbertson said in reference to Catalys’ Liquid Optics Interface. “It took a substantial amount of time to develop all of the technology.”

In turn, the liquid interface created other benefits that Dr. Culbertson noticed in different aspects of the procedure. There was almost no subconjunctival hemorrhage, the patient did not lose his or her vision, and the system raised intraocular pressure only about 25 mm Hg. It was also more comfortable for the patient. Although the interface was the biggest refinement made to the Catalys platform, Dr. Culbertson said some ergonomic refinements were also needed, including the graphical user interfaces, the imaging screen positioning, and the handpieces.

“I think that, as the years go by, there will be different iterations of the machine, similar to how the phaco machine started as the size of a tank and has become a compact machine,” Dr. Culbertson said. “But I don’t think that the system needs further refinements for commercial use.”

The bottom line, Dr. Culbertson said, is that laser cataract surgery is here, it is ready for commercial use, and it is generally accepted as a technology that will improve the safety and the benefits of cataract surgery.

“IntraLase [Abbott Medical Optics Inc., Santa Ana, California] started off some years ago with little acceptance by ophthalmologists who were dubious about whether its use had advantages and who were especially skeptical about how they were going to pay for it,” Dr. Culbertson said. “In comparison, I think there is more generalized acceptance of the precision and accuracy that femtosecond lasers can bring to cataract surgery because of the IntraLase experience. As doctors hear more of the benefits and the safety femtosecond lasers bring to cataract surgery, I think they will start adopting it. They will find ways to finance it, and they will find ways to make [the laser] pay for itself.”

Therefore, the biggest barrier (aside from FDA regulations in the United States) may be how quickly companies can build these units, he said. Dr. Culbertson is optimistic: “I think in the next year we will see more distribution of these machines and, as they are assembled, gradually distributed to a small fraction of surgeons.”

CONCLUSION

There is a wealth of information at surgeons’ fingertips regarding the benefits of laser cataract surgery and its potential to revolutionize lens-based procedures. In order not to be left behind, surgeons should familiarize themselves with the technology now, in advance of its availability.

“I do think that laser cataract surgery will become the preferred way to take out cataracts, much like how LASIK became what patients requested for refractive surgery,” Dr. Slade said. “Laser cataract surgery will also give us more accurate refractive results. This is important because patients are looking for two things: They are looking for safety, and they are looking to see without glasses after cataract surgery.”

Practitioners who have used the technology agree that laser cataract surgery may move patients closer to the goal of spectacle independence. However, the question remains: How long will they have to wait to undergo this procedure in a nearby practice?

Gerd U. Auffarth, MD, is Acting Chairman of the Department of Ophthalmology, University of Heidelberg, Germany. Professor Auffarth states that he has no financial interest in the products or companies mentioned. He may be reached at e-mail: ga@uni-hd.de.

William W. Culbertson, MD, is the Lou Higgins Professor of Ophthalmology and Director of the Cornea Service and Refractive Surgery at Bascom Palmer Eye Institute, University of Miami. Dr. Culbertson states that he is a consultant to OptiMedica Corp. He may be reached at e-mail: wculbertson@ med.miami.edu.

William J. Fishkind, MD, is the Codirector of Fishkind and Bakewell Eye Care and Surgery Center, Tucson, Arizona, and a Clinical Professor of Ophthalmology at the University of Utah, Salt Lake City. Dr. Fishkind states that he is a consultant to LensAR. He may be reached at tel: +1 520 293 6740; e-mail: wfishkind@earthlink.net.

Michael C. Knorz, MD, is the Medical Director, FreeVis LASIK Center, Medical Faculty Mannheim, University of Heidelberg, Germany. Dr. Knorz states that he is a paid consultant to LenSx/Alcon Laboratories, Inc., and Abbott Medical Optics Inc. He is also a member of the CRST Europe Editorial Board. Dr. Knorz may be reached at e-mail: knorz@eyes.de.

Shareef Mahdavi is the president of SM2 Strategic. He states that he has no financial interest in the products or companies mentioned. Mr. Mahdavi may be reached at tel: +1 925 4259900; e-mail: shareef@sm2strategic.com.

Zoltan Nagy, MD, is a Clinical Professor in the Department of Ophthalmology at Semmelweis University, Budapest, Hungary. Dr. Nagy states that he is a consultant to LenSx/Alcon Laboratories, Inc. He may be reached at e-mail: nz@szem1.sote.hu.

Kasu Prasad Reddy, MD, practices at Maxivision Eye Centre in India. Dr. Reddy states that he has no financial interest in the products or companies mentioned. He may be reached at e-mail: kasuprasadreddy@gmail.com.

Stephen G. Slade, MD, FACS, is a surgeon at Slade and Baker Vision in Houston. Dr. Slade is the Chief Medical Editor of CRST Europe’s sister publication. Dr. Slade states that he is a consultant to LenSx/Alcon Laboratories, Inc. He may be reached at tel: +1 713 626 5544; e-mail: sgs@visiontexas.com.

  1. Nagy Z.Paper presented at:the European Society of Cataract and Refractive Surgeons Winter Meeting;Istanbul,Turkey; February 19,2011.
  2. Mahdavi S.Laser cataract surgery:The next new thing in ophthalmology.Cataract & Refractive Surgery Today.2011;10(3):83-87.
  3. Slade SG,Culbertson WW,Krueger RR.Femtosecond lasers for refractive cataract surgery.Cataract & Refractive Surgery Today. 2010;9(8):67-73.
  4. Hill WE.The importance of the capsulorrhexis—does it really matter? Presented for LensAR at:the Annual Meeting of the American Academy of Ophthalmology;October 16,2010;Chicago.
  5. Hill WE.The component parts of IOL power calculations.Paper presented at:the 25th Asia-Pacific Academy of Ophthalmology and the 15th Congress of the Chinese Ophthalmological Society;September 19,2010;Beijing.
  6. Hill WE.Robert M.Curts Lecture in Ophthalmology.Presented at:the Department of Ophthalmology,Dartmouth University; June 2,2010;Lebanon,New Hampshire.
  7. Hill WE.Sean B.Murphy Lecture in Ophthalmology.Presented at:the Department of Ophthalmology,McGill University;June 5,2009;Montreal,Canada.
  8. Auffarth G.Preliminary investigation into a new femtosecond laser cataract surgery procedure.Paper presented at:the European Society of Cataract and Refractive Surgeons Winter Meeting;February 19,2011;Istanbul,Turkey.

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