Transcription:
Collaborations and Controversies: Femtosecond Laser Cataract Surgery

Melanie Cole (Host):  Welcome to Better Edge, medicine. Podcast for physicians. Melanie Cole. And I invite you to listen. we examine the femtosecond laser cataract surgery modern contemporary cataract surgery, controversies and collaborations. Joining me in this panel is Dr. Robert Feder. He's the Director of Cornea Service and a Professor of Ophthalmology at Northwestern Medicine. And Dr. Surendra Basti. He's the Director of Cataract Service and a Professor of Ophthalmology at Northwestern Medicine. Gentlemen, it's a pleasure to have you join us today. We have a fascinating topic this panel discussion. Dr. Feder, I'd like to start with you. Can you share a little bit with us about the evolution of cataract surgery?

Robert Feder, MD (Guest): Oh, yeah. First, I'd like to mention that Dr. Basti has been a valued colleague and friend for many years and I have a great deal of respect for his only his surgical ability, but his constant drive to bring new technology to Northwestern. can recall when a patient was admitted to the hospital, had their surgery and then stayed in the hospital for four or five days after the surgery.

And now the surgery is done with topical anesthesia, with light sedation. The surgery is completed in 20 minutes It’s one of the most successful surgeries in the history of medicine, highly sophisticated. It's continually evolving. It's performed efficiently, safely, and painlessly by experienced surgeons around the country and around the world. it's a surgery that all, cataract surgeons have come to perform for the benefit of their patients.

Host: Dr. Basti, can you share the latest updates for us on femtosecond laser cataract surgery? What is it, and there seems to be controversy around this approach. Can you share some of those factors that are part of this controversy? What are some of the opinions that differ among surgeons regarding techniques and safety, complications? Kind of summarize it for us.

Surendra Basti, MD (Guest): Just to piggyback on what Dr. Feder just mentioned, cataract surgery conventional, traditional cataract surgery has come a very long way and is providing very predictable results. Femtosecond laser surgery is one of the major technological advances that helps automate many of the steps of cataract surgery. So, that's the allure of

Dr. Basti: femtosecond laser

Surendra Basti, MD (Guest): Cataract surgery in that, by automating many steps, it makes them very predictable.

And it was FDA approved in 2012. And I would say the major advances in the field of femtosecond laser cataract surgery are mostly to do with technology that makes imaging the cataract very accurate. And more recently the advance that's just on the pipeline is imaging that involves not just the cataract, but the surface of the eye as well.

Why is that important? Well, it's important because an important goal of cataract surgery is not just removing the cataract, but correcting the patient’s refractive error near side astigmatism. And if you can accurately also image the surface of the eye, then it provides us landmarks that the laser can identify and predictably place incisions to correct astigmatism, or when we are using what we call toric lenses, the femtosecond laser can prompt us to the direction where the astigmatic correction should happen. So, the major advance it's just down the pipeline of femtosecond laser cataract surgery is imaging that not only involves the cataract, but also the surface of the eye. And this just compliments what cataract surgery can do for us with giving people eyeglass freedom.

Dr. Feder: So I can jump in there. Surendra just to mention that, to date the femtosecond laser shown statistical differences statistical benefit in terms of the time it takes to break up the cataract and the ability to make a perfect circle, a perfect centered circle to gain access to the cataract.

the point that's important is to recognize this statistical significance is not the same as clinical significant difference. So you can show that statistically, the femtosecond laser can do certain functions reliably, but how does that translate to clinical outcomes and to date the femtosecond laser hasn't really shown a dramatic improvement in outcomes for patients. The femtosecond laser in experienced hands like yours doesn't really add much time to the surgery, but for most surgeons, surgery does take longer. It's more costly. and it’s not available for all patients who want to have a cataract surgery with the laser. Only certain patients who are having astigmatism correction or those who are getting special implants have access to the femto laser.

Dr. Basti: I agree with that Rob. I do think that the femtosecond laser clearly adds time and cost to the surgical procedure, and those are major deterrents to widespread adoption of this technology. I think that the other perhaps critique of femtosecond laser cataract surgery is that cross-sectional studies performed both in the United States and in Europe haven't really demonstrated a major advantage in terms of complication rates or in terms of visual acuity at one point. The reason I continue to advocate for femtosecond laser cataract surgery, is that the aspect of it, that's very clear that most surgeons agree on, is the predictability of the capsulorhexis and the advantage of having a predictable capsulorhexis is that retention of vision results is likely to be the best when you have a predictable capsulotomy.

What I mean by that is, if we achieved a particular goal for a patient and either in terms of eyeglass freedom or the refractive error that we achieved, the likelihood of that being maintained over time is the highest when your capsulotomy is well centered and of a predictable size and those two aspects truly haven't been studied, meaning longitudinal retention of vision results is one aspect that I think we are still looking for in terms of validation. Just intuitively as an important step of cataract surgery, capsulorhexis really is the major, step that determines how well the lens sits in the eye and knowing that the femtosecond laser does that predictably gives me strong sense that this is really the major aspect of surgery that can be advantageous to patients. So that's what drives me into continuing to use the femtosecond laser for our patients.

Dr. Feder: So one of the things that the listening audience would probably want to know is does an experienced cataract surgeon who does not use the femtosecond laser is that surgeon capable of making a centered and fairly round and reliable capsulotomy? And does the incremental improvement that the femtosecond laser offers is that incremental difference clinically significant? It may be, and probably is statistically significant, but maybe not clinically important. The other thing that's important to know is that the femtosecond laser has some unique associated risks including the capsulorhexis, capsulorhexis performed with the femtosecond laser is not really a continuous tear capsulotomy, which is the kind that we with modern cataract surgery. It’s more of a postage stamp capsulotomy and postage stamp capsulotomies are more at risk for radial tears, then the continuous tear capsulotomy. So even though it's centered and even though it's perfectly round, it does add additional risk albeit not great risk, but it's more risk than a smooth, continuous tear capsulotomy.

Dr. Basti: Yes. I agree with that. That was a revelation. I don't think any of us expected that the good news though, is the posted standard appearance is something that one sees when we look at it with an electron microscope where the magnification is several thousand times of the edge of the capsulotomy. In the real worldlike you mentioned, Rob, I do concede that if you really put a lot of force on the age of the capsulotomy a femtosecond capsulotomy indeed can extend the good news is in a practical sense, I don't view this as a real risk. I mean very candidly I've probably done 5,000 of these procedures over the past seven, eight years.

And I can't think of more than one or two instances where the capsulotomy extended. That happens even if it's the manual capsulotomy, where we do something that extends the capsulotomy. Smouch as the postage stamp appearance is a true aspect of femtosecond laser cataract surgery, in practical terms, I don't think that becomes a major deterrent since one of our goals with cataract surgery is not really to stress that capsulorhexis.

Dr. Feder: That's great to hear. One other thing I heard you say Surendra, which I was happy to hear that newer technology will help to determine the access for astigmatism surgery. One of the purported advantages for the femtosecond laser is the ability to create peripheral incisions in the cornea can help reduce astigmatism. But one of the issues that I've had with femtosecond laser is there hasn't been a way of   for cyclooctadiene. When we put in a Toric lens implants, or when we do a LASIK surgery, a lot of technology is brought to bear to make sure that we compensate for cyclorotation.

When a patient lays back in the eye, rotates axis where you think you would be putting those incisions might be in a different place. And the femtosecond laser to this point, has not had any technology for correcting cyclorotation. So if the patient's eye is rotated and you weren't aware of it, incisions, however beautifully they're made, could be placed the wrong axis. So, I heard you say that coming down the pike, there's going to be an effort to improve placement of the incisions. Did I get that right Surendra? Did I hear you correctly?

Dr. Basti: Yes, Rob indeed up to this point, the past seven years, if we placed incisions with the femtosecond laser, we had to use a marker on the eye, but the patient seated and that marker should be the kind that's visible when the femtosecond laser images the eye so the marker we have to use as a special marker that we had to place on the eye.

And like most surgeons agree, marking the eye is not the most accurate way to determine anatomic landmarks. One of the nice things that's happened in the field of femtosecond laser cataract surgery is about six months ago, the FDA approved a technology called the Cassini imaging device. And that device talks to the femtosecond laser in that whatever it measures as anatomic landmarks are then fed into the femtosecond laser software.

So, that it can identify those landmarks when it images the eye and therefore, place the incisions more accurately. So indeed what was a disadvantage of not compensating for cyclorotation will be overcome with harnessing the technology that Cassini provides. The challenge though, Rob I must admit is cost and you know, having a Cassini device adds cost. Imaging that just before femtosecond laser surgery, he adds another 30 seconds. So both costs and time, major deterrents to femtosecond lasers being widespread used There will continue to remain downsides of using this technology with cataract surgery, but it does provide the accuracy that we are looking for in terms of anatomic landmarks.

Dr. Feder: So at the present time, in terms of patient outcomes, and being cost-effective one would have to say the femtosecond laser for cataract surgery doesn't quite those marks. we think of femtosecond laser surgery for LASIK surgery there’s tremendous improvement that's afforded beyond a mechanical microkeratome to be able to use the laser to make the flap, patients are treated more safely. And the flaps are probably more predictable allowing us to treat patients that we couldn't otherwise treat. But with femtosecond laser for cataract surgery, we're not really seeing the benefit in any of the parameters that we would judge any surgery.

And so if a patient is at the present time, if the patient is looking for the best surgery, you would be hard pressed to say that the femtosecond laser has significant clinical advantages over contemporary cataract surgery. My hope is that in the future, we'll have a real benefit to being able to create the capsulotomy as you described, be able to place the astigmatism incisions properly. Maybe certain implants will be particularly beneficial when used with the femtosecond laser, but present time, just doesn't seem like it's there yet. Do you feel differently?

Dr. Basti: What I might add to what you just said, Rob is the following, I don't think it's necessary to use the femtosecond laser in every single case of cataract surgery. So surgeons who don't have a femtosecond laser, don't need to feel that they are not doing what state-of-the-art is in cataract surgery. Those of us who have access to the femtosecond laser, to me, it seems like a no-brainer to use it in situations where eyeglass freedom is an important outcome. So, that's one group of patients that we all routinely get about 25% of many of our practices. Folks who need eyeglass freedom with the kind of lenses that we have available that provide that. In those group of patients, I think the femtosecond laser is the perfect complement to what the lens itself can do, just because of the accuracy and the precision that it provides to cataract surgery. So that's one group that I feel fairly strongly that the femtosecond laser can be a huge asset to those of us who have access to it.

The second group of patients are those who have unique situations in their eyes, patients where their corneal endothelium is not perfectly healthy or patients whose eye anatomy, for instance zonules are a little bit weak. In those instances, the femtosecond laser and its benefits are very well-defined in terms of being advantageous. So, I would say those of us who have access to the femtosecond laser can clearly harness some of the true benefits of the femtosecond laser in these two groups of patients. Folks who don't have the laser for routine use, I don't think you need to feel like you're missing something here. I think modern cataract surgery does provide good outcomes even with manual techniques.

Host: Dr. Feder, do you have any final thoughts you'd like to add? And I'd like to give you each chance to of wrap this up to let other providers know what you would like them to know about what you're doing at Northwestern Medicine, the Department of Ophthalmology and what you're offering there.

Dr. Feder: So I would just as a counterpoint mentioned that while I agree that in special situations, the femtosecond laser may have some advantages in cataract surgery for the lion's share of patients, the vast majority of patients, even the patients who are hoping to have glasses free outcomes modern cataract surgery fits the bill in a more cost-effective and safe manner.

Finally, the training of residents, is I think compromised when they're doing the majority of their surgery with the femtosecond laser, because they won't learn the skills, they need to do a contemporary cataract surgery without the laser. Northwestern is a fabulous place to practice ophthalmology and to be treated if you're a patient, because we've got wonderful surgeons like Dr. Basti and we are providing high quality care to our patients. It's a big institution, but the people involved really have a patients first mentality. So that in conclusion I would just say that I think contemporary cataract surgery is a highly successful, very effective safe procedure with great outcomes. And you have the luxury of having a femtosecond laser for specific situations, unique situations, it can be of value.

Melanie Cole (Host): And Dr. Basti, last word to you.

Dr. Basti: Well, I think you know, Northwestern Medicine is clearly the place for modern cataract surgery. Literally every iteration that we have available for cataract surgery is available or on the way to being available at Northwestern Medicine. So, we take great pride in truly having technology, that's state of the art in cataract surgery at Northwestern Medicine.

What are the important things that we are trying to accomplish is not just providing the state of the art, but trying to expand on indications that technology can provide. We've done that with the femtosecond laser, with our publications on the field, showing its value in different clinical situations, which are complex for us to manage without the laser. So we do pride ourselves at Northwestern Medicine in not just harnessing good technology, but also expanding on its indications by utilizing it in different situations. All of this can be useful to patients. It can be useful to surgeons who don't have access to this technology, but want the best for their patients.

Melanie Cole (Host): Thank you gentlemen so much. What an absolutely fascinating episode. Thank you for joining us and sharing your incredible expertise. We invite you to come back on and update us as things change. To refer your patient, please visit our website@nm.org to get connected with one of our providers. That concludes this episode of Better Edge, a Northwestern Medicine Podcast for Physicians. Please remember to subscribe, rate and review this podcast and all the other Northwestern Medicine Podcasts. I'm Melanie Cole.