Femto Mania Continues: More Choices
Roger F. Steinert, MD: Hello. I am Dr. Roger Steinert, Director of the Gavin Herbert Eye Institute at the University of California, Irvine. By Skype™, I have with me 2 distinguished panelists -- Dr. Steve Lane and Dr. Tom Samuelson -- and we are going to be speaking about some of the highlights of the just-concluded annual meeting of the American Society of Cataract and Refractive Surgery (ASCRS).
Steve, tell us a little bit about yourself.
Stephen S. Lane, MD: My name is Stephen Lane. I'm from St. Paul, Minnesota, where I practice cornea and external disease, as well as refractive surgery and cataract surgery.
Dr. Steinert: Welcome, Steve. And Tom?
Thomas W. Samuelson, MD: My name is Tom Samuelson. I am a glaucoma anterior-segment surgeon in Minneapolis, right across the river from Steve. I have a practice at Minnesota Eye Consultants, and I also teach residents through the University of Minnesota. I am on the clinical faculty at Hennepin County Medical Center.
Dr. Steinert: Thank you both for taking the time to join Medscape.
ASCRS was filled with lots of exciting and new areas. One of the biggest topics still out there is femtosecond ("femto") laser cataract surgery. Steve, what is going on here? Is this still growing? Is it guaranteed to be taking over? Have you heard anything negative?
Dr. Lane: It is a very controversial subject, but certainly the interest continues to grow almost exponentially. Several different laser platforms are now available, and that is probably the most new and exciting development. Physicians in the United States now have a choice of 4 different lasers.
We are starting to see some results. The applicability and adjustability of many of the features are continuing to increase. The technology continues to evolve in a very short period of time. We are seeing an increased number of procedures, and an increased amount of interest.
There is still healthy skepticism and a lot of active debate. Cost probably remains the most significant barrier to the uptick of this technology, but we are starting to see how we can get better results in complicated cases, for example.
It remains a very exciting field. It will be the future (as everybody predicts), but we need to get a better handle on the financial aspects of it under most circumstances for it to continue to gain even more widespread applicability.
Dr. Steinert: Complications are not nonexistent with femto; they seem to be running at about the same level as conventional surgery, even for very skilled surgeons using conventional ultrasound. So, we are moving past that. We have been seeing many more presentations on the technical issues and refinements.
On the exhibit floor, the activity at the booths of the 4 current manufacturers was very high, and it sounds like Ziemer is about to enter the market as well, so pretty soon we may have a fifth platform.
Dr. Lane: I certainly agree with that. We are starting to see this becoming a much more portable type of technology. Buying it and having it stand in your ambulatory surgical center alone is evolving as well. Several companies are making their lasers mobile so that they travel around, and we are seeing that as an increasingly useful modality for people to get experience with it and make a decision about whether they want to purchase the device or use it in a mobile fashion coming off of a van. That seems to be working very well for many ophthalmologists.
Dr. Steinert: That makes it more of a game-changer, because it will make it more affordable as well as more accessible.
A Home Run for Microinvasive Glaucoma Surgery
Dr. Steinert: Equal to the femto mania is the microinvasive glaucoma surgery (MIGS) mania. The whole meeting was filled with the buzz over the innovations in glaucoma surgery. Tom, what's your take on all of this?
Dr. Samuelson: In many respects, it was a home run meeting for glaucoma in general and MIGS in particular. It was a home run in general because Rick Lewis, one of our glaucoma brethren, was honored with the presidency of ASCRS. Then, in the surgical section on glaucoma day, we had nearly 1000 people in the room -- which for glaucoma at an ASCRS meeting is pretty impressive. Of course, nothing is more mainstream at ASCRS than the Binkhorst Lecture, and Ike Ahmed gave a fantastic talk on MIGS. So MIGS had a huge coming-out party at ASCRS, and it was great to see.
Dr. Steinert: Thus far, all of the MIGS has been combined with cataract surgery, yet we know that traditionally, most glaucoma surgery has been separate from cataract surgery. Are these microtechniques going to make their way into non-cataract surgery applications?
Dr. Samuelson: I think they will, but MIGS will probably continue to be centered around cataract surgery. In the past, we decoupled cataract and glaucoma surgery because after we learned that clear corneal phacoemulsification ("phaco") lowered pressure by itself in a large proportion of patients and retained all future surgical glaucoma options, we stopped doing combined procedures except for cases of extremely advanced disease or very high intraocular pressure. We were doing phaco alone for many years for mild to moderate glaucoma, but now that MIGS has evolved, we are using the phaco platform to provide an adjunct to the procedure by adding on a MIGS-plus type of procedure -- whether it is an iStent®, Trabectome®, or endoscopic cyclophotocoagulation.
The iStent seems to have all the attention right now and is gaining a lot of momentum, and there was tremendous interest at ASCRS. I taught 3 courses on MIGS technology with an emphasis on iStent, and there were other courses as well. It lends itself very nicely to be done in conjunction with cataract surgery.
The benefit that we have for treating glaucoma these days is that we can take advantage of our newer laser platforms and our improved pharmacology; we can manage most glaucoma until the patient develops a visually significant cataract, and then we can manage both problems at the same time. It doesn't cure glaucoma. I want to make sure that people don't think that glaucoma has been cured and we can move on to a different disease now.
We have a lot of work to do still, but the benefit of iStent, in particular, is the safety. The safety profile of iStent in the US premarket approval trial was not measurably different from cataract surgery alone at 2 years. There was no difference in visual outcomes or in adverse events between cataract surgery alone and cataract surgery plus iStent. That safety benefit is enormous. Now that we can perform a glaucoma procedure at the same time as cataract surgery without affecting the visual or refractive outcomes of cataract surgery, but still lower the intraocular pressure and reduce the need for medications -- that is a great advance.
The reality is that our more advanced surgical procedures, such as filtration surgery, and our aqueous drainage devices are getting better and safer as well, but the big advance at ASCRS this year is the tremendous interest in this new category we call MIGS.
Dr. Steinert: Every discussion and symposium involving MIGS was jammed at ASCRS. As a cornea-oriented person, I have increasingly been thinking of glaucoma drops as toxins, because we see more cases not just of allergy -- which is bad enough from a patient's point of view -- but actual limbal stem cell deficiency and sometimes almost intractable surface damage. When you talk to a patient who is on glaucoma medication about the MIGS option, my experience so far has been that that is about a 30-second discussion and then they leap into it, because they don't like the drops either.
Steve, you are a cornea specialist. What are your thoughts?
Dr. Lane: My experience is the same. The discussion with patients is pretty simple and straightforward. If you say there is a chance that we might be able to get rid of 1 or more of your drops, the patient is all over that.
The other important thing, from an external disease standpoint, is the whole concept of dry eye and the problems that arise from glaucoma medications with respect to dry eye symptoms and to the ocular surface. Being able to reduce that toxic load to the surface is very important as well.
Formulas Made Easy
Dr. Steinert: Shifting back to the cataract side of things, Warren Hill gave the Innovator's Lecture on his work toward improving the accuracy of the formula for calculating intraocular lenses (IOLs). Then, the ASCRS Website has been privileged to bring on Graham Barrett's latest update on his formula. Can you give us some comments on that?
Dr. Lane: ASCRS has made the Barrett Toric Calculator available on their Website. Go to the drop-down menu under "Online Tools"; you will find it there.
What is different about this formula compared with some of the others is that the posterior corneal astigmatism estimation is automatically added to this formula. So the outcomes have lined up nicely with my initial experience with Doug Koch's posterior corneal astigmatism algorithm, which I think has been found to be very accurate and invaluable.
There are other options that ophthalmologists can explore. I would invite them to look at this as a wonderful new formula.
In keeping with the idea of trying to improve outcomes, Warren gave his typical intellectual experience, in that went through his current thinking on the various algorithms and what he is doing to try and improve on the outcomes of the formulas, in terms of looking at probabilities and matching these with the algorithms. With this addition, he has been able to improve outcomes in some of the early results, and I have no doubt that Warren will continue this work and help us all achieve better results through formulas alone.
So, we are seeing this perfect storm where the technology is improving to allow us to get better results, such as intraoperative aberrometry (another very big topic at this meeting) and some of the guidance devices that are available to help us put toric IOLs and limbal-relaxing incisions on alignment, as well as the improvements with the indirect measurements with the formulas. We are getting a better handle all the time on reaching that Holy Grail of improving results in cataract surgery so they can mimic what we have been able to do with corneal refractive surgery.
Dr. Steinert: That's certainly true. The overall market information and the surveys of the audience at ASCRS seem to indicate that although the adoption of multifocal and accommodating IOLs is relatively flat, the adoption and incorporation of astigmatism correction are growing at a very rapid rate -- 2%-3% per year, typically -- and any time there was a discussion about astigmatism (especially accuracy of placement of the lens), there was a lot of audience interest because it's a great technology. Like MIGS, it allows patients to experience something better and improves their quality of life overall as well as the quality of their optics.
Drug-Delivery Systems Moving Closer
Dr. Steinert: We are hearing more interesting material about potential new pharmaceuticals as well. Tom, what did you hear about pharmaceuticals at the meeting?
Dr. Samuelson: Although we are still a few years away, momentum is increasing for new drug-delivery systems. Whether it is depot injections or impregnated drug delivery with punctal plugs, there is interest in improving the way we administer medication. We are hoping that we can couple safe, efficacious surgical procedures with drug delivery that can reduce the burden of the everyday topical administration that we have always had to use.
As you mentioned earlier, we are seeing surface toxicity with some of the complex drug regimens. If we can avoid having to administer complex drug regimens 2-4 times a day and replace them with a 1-, 2-, or 3-month duration delivery system, it would be a huge advance. Evidence suggests that we may experience a pharmacologic renaissance within the next few years similar to the surgical renaissance we are seeing now.
Dr. Steinert: The drug-delivery system concept, in terms of a steady state of a low dose as opposed to pulsed delivery (which is what we largely do with drops), may lead to some very interesting new results. Is it better to have pulses of high levels or to have a low-level steady state with some of these drugs, particularly the anti-inflammatory agents? It will be interesting to find out, but it certainly would help compliance to have a drug-delivery system that didn't rely on patients taking drops.
Steve, you and I have talked about some of the other new options, such as intraoperative pharmaceuticals.
Dr. Lane: That is another very exciting area. The whole field of nanotechnology is really taking off, and to be able to deliver smaller amounts of drops that are absorbed so much better, and not necessarily through the cornea, is also of great interest and potential on the horizon, to go along with the renaissance that Tom was talking about.
Intraoperatively, many of us have used different off-label medications for years -- either in our balanced salt solution (BSS) bottle or directly into the eye -- both for anesthetic effects and maintenance of pupillary mydriasis. Several pharmaceutical agents going through the process of US Food and Drug Administration (FDA) approval now may be approved; these will be able to be injected into the bottle and will improve both pain and mydriasis intraoperatively, with a product that will be available commercially. It will take away the off-label aspect and the need for compounding that can be problematic in terms of toxic anterior segment syndrome and other infectious conditions that can occur as a result of compounding. It is another exciting area that mixes pharmacology with surgery.
The Possibility of Correcting Presbyopia With an Eye Drop
Dr. Steinert: Shifting slightly, we have been hearing a lot about the pending availability of the AcuFocus™ KAMRA™ (Irvine, California) pinhole intracorneal inlay for presbyopia. In other areas of presbyopia, we are hearing about a new generation of multifocal and extended depth-of-focus IOLs that seem to be on the horizon, and we are hearing about the ReVision Optics® Raindrop® (Lake Forest, California) intracorneal inlay.
Something less expected on the drug side was the idea of having a miotic agent that would also create the equivalent of a pinhole aperture, but one that does not have the spasm of accommodation and the pain associated with pilocarpine.
Dr. Lane: We weren't given a lot of detail, but your description is right on target. If that is the case, and we can improve and essentially cure presbyopia with an eye drop, that's more than a renaissance -- it's a revolution at that point, and it holds some very interesting promise.
It does have some limitations. The drop lasts about 8 hours, so it's certainly not acute. It's a conjunctival injection. There might be a little discomfort upon instillation, as well some stinging, but it would make an interesting adjunct to our armamentarium to be able to correct presbyopia for 8 hours a day with a single drop. I would be all over that.
Dr. Steinert: We will get those glasses off you, Steve.
Dr. Lane: Exactly.
Will Crosslinking Finally Be Approved?
Dr. Steinert: The last thing I want to discuss is crosslinking. We have been hearing about corneal crosslinking for keratoconus out of Europe for a decade, and we hope that the basic application will finally receive FDA approval this year. I was intrigued by the increasing information about selective application of crosslinking for optical reasons -- perhaps correction of astigmatism or correcting some of the irregularity in keratoconus. One thing that I heard about last year in Europe, and now we have heard a fair amount at ASCRS, was the combination of riboflavin and ultraviolet for the treatment of infectious keratitis.
Dr. Lane: It is very exciting. Just like in glaucoma, we have continued to show tremendous advances in cornea when you look back over the past several years, first with Descemet-stripping lamellar endokeratoplasty (DSEK) and deep anterior lamellar keratoplasty (DALK), and now with crosslinking. We would love to have in our hands the ability to crosslink patients with some of the ectasias or keratoconus -- the kinds of patients who are doomed to either long-term contact lens wear or surgery down the line. If we were able to halt that, as crosslinking suggests it will be able to do, what a wonderful thing it would be for patients, to be able to take care of them at a much younger age.
In terms of infectious keratitis -- especially severe, recalcitrant infectious keratitis -- to be able to halt it and kill those bugs right on the spot, and to supplement it with the topical agent, would be a breakthrough and would probably save many corneas. We look forward to the studies and the information coming out about that. Like so many things, it makes sense that it would work, and now it's just a matter of us proving it so that we can have it at our disposal here in the United States.
Dr. Steinert: I would like to thank Dr. Tom Samuelson and Dr. Stephen Lane for giving us their time. This has been a great discussion, touching on just a few of the hundreds of exciting areas that were incorporated into the annual meeting of ASCRS in Boston. On behalf of Medscape Ophthalmology, thank you very much for listening.
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Cite this: A 'Perfect Storm' in Ophthalmology - Medscape - May 15, 2014.