From Semiconductor Physics to Clinical Optics

How did you make the leap from physics to eye research?

When I was writing my physics thesis, I was running out of money because it had all been spent on our research project. My professor offered to help me find a job – I needed one simply to survive at that point – and he found me a position at a university eye clinic. At the time, their research involved using magnetic fields to remove foreign bodies from the eye, and I happened to be a specialist in magnetic fields. So I started working for the clinic, performing diagnostic ultrasounds, making sure the equipment was maintained, and doing some basic research. Implanting IOLs became an ever bigger part of our work, so it was necessary to decide how to do the calculations, and this was an easy game for a physicist! That’s how I got into IOL calculation optics and measurement techniques. And my professional goal became to maintain and improve the quality of IOL calculations and outcomes.

What do you think the next steps in improving biometry will be?

I think we are very close to the final limits. We can now observe how the dimensions of the eye change during the day – for example, we are all a little bit more myopic around noon. These are tiny measurements – around 5–10 microns – but the technology we have now can make them accurately. These tiny changes in eye length aren’t optics, though, they’re just physiology. It’s like using a sports car to go to the shop around the corner for cigarettes. With biometry, we have a sports car, and we can go very, very fast, but there’s no actual need for even higher accuracy than we can already achieve today.

What improvements would you like to see in ophthalmology?

I think interdisciplinary work is crucial – for example, I think we should be working with molecular biologists when we seek to answer questions like “What happens to the zonules?” and “How is wound healing different in different people?”

There are things we can’t tell just from looking at the eye, and we need to explore other aspects, rather than simply the optical or the physical ones.

How does medicine differ from physics?

My profession has definitely influenced my career – I am a physicist, and I have a mathematical background, but I’ve also gained an understanding of medical procedures. It’s a translation from the medical laboratory to the patient, because ultimately it’s the patient for whom you work. So I may get a telephone call from someone asking “What should I implant in this patient?” I don’t know the whole story, I will only see part of it, but the person on the telephone will keep insisting that I choose the lens. So I have to come up with a number and a lens – the patient is already under general anesthesia and a decision must be made.

When I worked in physics, I could lie back on my sofa, sip on a cup of coffee and think things over, but in medicine you have to make quick decisions on the basis of incomplete data. Fortunately, you get used to this – the stressful situations become less common as you learn how to be organized and plan for this different way of working.

Is working with doctors hard?

It’s not hard, but it is different. In a university clinic there are positions for different medical staff, but not for physicists – throughout the years, I have been an exotic presence in medical settings, and I think I still am.

There are other people with their names attached to IOL calculation formulae. Do you view them as competitors?

Well, scientifically they are my competitors of course. But we also work together – around 15 years ago, many pirated versions of IOL formulae software were appearing online (something that still happens to this day), and these were not safe or accurate to use. We banded together to release a joint statement, to make it clear that no one should be using these formulae, and every so often we still have to address these kinds of issues. This is how the IOL Power Club came about. So I would say we have a good relationship, but of course we are all scientists, and eager to better each other!

If you could start over, would you do anything differently?

I would do it all again, although it hasn’t always been easy – making a career as a physicist in a medical field in Germany wasn’t without challenges, as this type of interdisciplinary work isn’t always commonplace. In other countries such as the UK, as far as I know, you are more likely to see a chemist, a mathematician and a physicist (and so on) working together happily, but this is not so easy in Germany.

Why do you think that is?

I don’t know. It has not been easy over the last 30 years, but I still don’t know why.

If you could give advice to your younger self, what would you say?

The work you did in physics was worthwhile, but now that you are looking for a career, it is the wrong place to be.