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Subspecialties Professional Development, Refractive

Being Theo Seiler


Theo Seiler topped The Ophthalmologist’s 2014 Power List, for good reason – he’s a refractive surgery pioneer, having developed the first clinical dye laser and invented corneal cross-linking. He performed the first ever PTK (phototherapeutic keratectomy), PRK (photorefractive keratectomy) and wavefront-laser guided surgical techniques on the human eye, and was also the first to combine LASIK and rapid corneal cross-linking.

Theo Seiler on…

Being Number One on The Power List

That was great! Everybody surrounded me and they found it very funny that I was wearing a pink dress on the cover! It was also a kind of surprise, as I’ve been working in this area for many, many years. I believe I’ve been lucky. Our work on the anterior segment has yielded a few important developments – like refractive surgery, cross-linking and new diagnostics in keratoconus – that have had some clinical value and happen to be used in some ophthalmologists’ daily work. These are things that have gained recognition for my group, but they are only a minor part of what we do.

Career highlights

The highlight was cross-linking. Back in the mid-to-late 1990s, everybody was performing LASIK, and we started to realize that we were producing keratoconus in some patients. Sometimes it happened, sometimes it didn’t, and at the time, we couldn’t see a reason for it. In 1998, we published the first cases of kerectasia after LASIK, not only did we detail the complications, but we also found a cure for them. The combination of discovering both is most probably the highlight of my career – the fact that it had value in treating non LASIK-induced keratoconus was a great side effect!

The current state of refractive surgery

If I have to be honest, refractive surgery, with current lasers and techniques, has plateaued. In terms of refractive success, we have a confidence of ±0.5 D, which is comparable to spectacles, and which you cannot improve on. You might be able to improve on safety a little, but it’s already very safe. Today, we have a complication risk of 0.1 percent, which is twice as good as contact lenses, which carry a 0.2 percent risk of infectious complications.

…and how it might be improved

What can we make better? Not the results, but the long-term stability and safety. And I believe that, in the long run, rather than removing corneal tissue with LASIK, we need to remove it with small incision lenticule extraction (SMILE). I believe that in 5 years, SMILE will have taken over the market. Unlike other laser refractive surgeries, it doesn’t really interfere with the biomechanical integrity of the cornea, meaning that you should no longer see cases of laser surgery-induced keratectasia. Having said that, I don’t believe the infrared femtosecond lasers we have today are precise enough do the job… but once we change the wavelength or the aperture of those lasers, we will be able to reach the same precision as we can with the excimer laser. This will take a while, but many companies are well on the way to improving their current systems.

The future of phakic IOLs

We implant these all the time – this is nothing special. The problem with phakic IOLs is when complications arise. If there is an infection after LASIK, in the worst case I would have to perform a corneal transplant; usually, I can handle it with antibiotics or a strong cross-linking. But if I have an infection inside the eye, those options are typically not possible – the eye’s defenses are on the outside, not the inside. Doing something inside the eye risks undermining its defenses and, if infection happens, the eye is lost.

In cataract surgery, the infection risk is 3 in 1000. It’s one thing taking that risk when it’s surgery for a good reason: the patients can’t see well because of a cataract. But it’s another thing taking that risk when patients can see perfectly well with contact lenses and glasses, which is why many of us refractive surgeons hesitate to use phakic IOLs.

Things going wrong more often than right

My old teacher told me, “If you start ten things at the same time and only one is successful, you are lucky.” I’ve been lucky four or five times in my life, with wavefront-guided LASIK, PRK, wavefront-optimized profiles, cross-linking, and combinations of cross-linking and other refractive surgery techniques. If I’ve done five, there will be nearly fifty more that weren’t successful – I certainly can’t remember them all!

One that I do remember clearly was holmium thermal laser keratoplasty. In 1989, we thought it was the best thing, but after a while, we realized that despite getting a huge effect in patients upfront, one year later the whole effect was gone. We had to go to the congresses, stand on the podium, and say, “I don’t do it anymore. It didn’t work. Period.”

My old teacher told me, ‘If you start ten things at the same time and only one is successful, you are lucky.’ I’ve been lucky four or five times in my life.
Moving from academia to IROC

Being honest, the true reason for founding the IROC was because the University of Zürich and I could not find a common platform to perform industry-based investigations. They always asked to participate moneywise and they wanted to influence the investigation. After a while, it just wasn’t working out anymore. We quit and Michael Mrochen and others just moved out. So we started the new clinic here in Zürich, which was very successful.

Forming IROC helped us push things, like cross-linking, forward. When I came to Zürich in 2000, I wanted to investigate cross-linking – you won’t believe how many objections I had from the university, reasons why I shouldn’t be doing cross-linking – even in an investigative setting. I found that straightforward investigative life wasn’t really possible at that time. I should say it has since changed.

Successfully straddling academia and industry

To succeed, I’ve learned two key things. First, never lie. Always tell the truth, whether it’s convenient to your industrial partner or not. It’s important that your colleagues believe you. Second, don’t take too much money from industry. I saw my industry partnerships as helping me to accomplish something, but I never used these partnerships to enhance my personal income. Whenever it comes to the patent, I usually leave that patent to the industry. I tell them I earn my money with my hands, and they are helping me to do my research.

To succeed, I’ve learned two key things. First, never lie. It’s important your colleagues believe you. Second, don’t take too much money from industry.
Current research interests

We’re looking at improving cross-linking. We want to move away from epi-off CXL, and try to bring the riboflavin into the stroma in a way that we can better titrate the cross-linking to enhance its effects by a factor of two or three – and make it less harmful to the eye.

We want to perform cross-linking where the cornea is weakest – and that can mean different layers in different people. This means customizing the cross-linking to the right depth. We can create tiny channels in the cornea with a UV femtosecond laser, where we inject the riboflavin to the appropriate depth for the patient. Thanks to our collaboration with Harvard Medical School, we can measure the biomechanical effect non-invasively and, therefore, titrate the cross-linking effectively. It’s very promising.

The great femtosecond laser versus manual rhexis in cataract surgery debate

The femtosecond laser makes the capsulorhexis safer – especially for less-experienced surgeons – and it is an easy way to avoid mistakes. If you don’t perform many cataract surgeries in a year, then it’s of great value in letting you sleep well! For a high volume, experienced surgeon, it doesn’t make much of a difference. I have the new laser from Ziemer and I use it to perform cataract surgery, but being honest, I don’t need it that much. My younger colleagues like it.

The current state of ophthalmology

Ever since ophthalmology’s inception, it has been in a constant stream of evolution. The generation before me introduced IOLs, the generation before that did the extracapsular cataract extraction… Every generation has brought in new insights and techniques, and so I don’t see that this is a particularly special time in ophthalmology. It’s not better, it’s not worse.

Exciting advances

In the anterior segment, the first big thing for me is new diagnostic modalities with high-res OCT. The next big thing is SMILE, which excites me a lot, because that is the future. In the posterior segment, I think that liquefying the vitreous by injection is fantastic (but expensive); we need to look at ways of making it less expensive. But for all parts of the eye, new things are coming. Gene therapy has been heralded as a wonder cure for years and years, but now we are coming closer to it being used in the clinic, which is exciting.

Issues that need addressing in the next decade

Presbyopia and accommodation – nobody’s really solved them. Right now, we can change the biomechanical stiffness of the lens with some femtosecond lasers, making accommodation possible again – in some patients. Alternatively, we may be able to refill the lens capsule after cataract extraction with fluid that, once cross-linked, generates a clear lens that can accommodate again. Those are the things that I am looking forward to seeing in the next 10 years.

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About the Author
Author Theo Seiler
Theo Seiler

Number one in our 2014 Power List, Theo Seiler is a pioneer of refractive surgery. Among his achievements are the development of the first clinical dye laser and the invention of corneal crosslinking (CXL); he also performed the first ever PTK, PRK and wavefront-laser guided surgical techniques on the human eye, and was the first to combine LASIK and rapid CXL.

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