Lindsay Machan, MD, FSIR, is an interventional radiologist at the Vancouver Hospital, an associate professor of radiology at the University of British Columbia and is an Order of Canada recipient.
Dr. Machan will be giving the Dr. Charles T. Dotter Lecture at SIR 2025. The Dotter Lecture was initiated in 1984 as an annual invited lecture to honor Dr. Dotter as one of the founders of interventional radiology.
Can you tell us about yourself and your career?
Lindsay Machan, MD, FSIR: I am an interventional radiologist at the University of British Columbia and Vancouver Hospital. I’m later in my career, and so I’ve lived through a lot of the evolution of interventional radiology.
I got my start here in Vancouver with a fellowship with one of the original interventional radiologists, Joachim Burhenne, MD, the first person to do a percutaneous gallstone extraction. From there, I was lucky enough to work in London at the Hammersmith Hospital under Professor David J. Allison, one of the first professors of radiology in the United Kingdom. He was co-editor of one of the definitive radiology textbooks at the time, and he was one of the first European practitioners of advanced embolization techniques. While there, I was also able to work alongside Andreas Adam, MD, FSIR.
I then went to work at the University of Pennsylvania, where I was able to work with Constantin Cope, MD, FSIR. He was one of the major inspirations in my career, and I was so lucky to be around him and exposed to his amazing mind and inquisitive nature. He’s the one who really formulated my thoughts on innovation.
I returned to Vancouver in the 1990s and have been here ever since. I’m fortunate, because when I started here, there was a very innovative vascular surgeon who I formed a collaborative endovascular group with—so I’ve learned about collaborating with other specialties and how important it is to have different people bringing different skill sets and knowledge to the table.
What are your clinical interests?
LM: As with all IRs, my clinical interests are an inch deep and a mile wide. One of the best descriptions I’ve ever heard of IR is from an interview with Laura Findeiss, MD, FSIR, who said that interventional radiology fills a void in care. I’d never thought of it like that, but that’s exactly what we’ve done, especially early on. We filled a void in care.
Early in my career, we did all kinds of vascular and nonvascular interventions. As we went along and technology matured, my practice became more focused. My interests right now in particular are women’s health and venous disease. From a research perspective, I’m interested in biologically active devices as well as radiation reduction.
You are also deeply involved in mentoring—what does that look like?
LM: A large part of my professional life is now mentoring young people. In particular, I’m involved in a national organization in Canada called The Creative Destruction Lab. It began as a collaboration with almost all the major business schools across Canada, and it’s taken off. We now have programs in Estonia, France, Hong Kong and the United States. It’s a great way to be exposed to early-career engineers and physicians with interesting ideas.
You’ve worked with so many luminaries of IR, many of whom have also delivered the Dotter Lecture. How does it feel to be named SIR’s 2025 Charles T. Dotter Lecturer?
LM: Honestly? I’m a bit terrified. When you’re tapped for an opportunity like this, the first thing you do is look at the lectures that have come before you—and it’s a bit scary, because all of them are inspiring. There’s a pressure to maintain a standard.
Realistically, people attend these lectures and it’s a passing event for the average person. But with any luck, there’s one or two people in the crowd who will hear something that resonates and will walk away feeling inspired. That’s what I’m hoping for.
What will your lecture cover this year?
LM: Well, all the good subjects are taken.
Jokes aside, there are so many aspects to actually being successful in interventional practice. Riad Salem, MD, FSIR, talked about mentorship. William S. Rilling, MD, FSIR, talked about embracing technology. Scott O. Trerotola, MD, FSIR, and Zeke Silva III, MD, FSIR, talked about competition. Ziv J Haskal, MD, FSIR, gave an amazing talk about the need to go from being the first in something to being a data-based specialty. All of these are essential to the success of IR. But in the 50th year of the society, as we celebrate our roots and Charles Dotter, one of the most important things we can do is to keep innovating—and that’s what I plan to talk about.
We describe ourselves as an innovative specialty, but what is the process of innovation? There are so many ways to be part of the innovative process, and I think it’s essential to the preservation of the specialty. It’s in our DNA. I think a lot of people are attracted to IR because we are always coming up with new solutions which, to quote Dr. Findeiss, fill a void in care. In challenges lie opportunities, and that’s something IR has always done very well.
It's very easy to have a doom-and-gloom perspective, especially considering the entire state of healthcare and how competitive the market is. Many people have seen that T-shirt that says, “Interventional radiology, inventing procedures for other specialties for 40 years.” In my view, the fact that we create these therapies and techniques that other specialties want to perform is a validation of how valuable our ideas are.
What do you consider to be some of the big challenges facing IRs?
LM: It depends on how you define challenges. I would say the biggest challenge is safety. We don’t talk about it enough in my mind. The IR suite is a hostile environment. Lead protection is very unergonomic. It’s not sexy to talk about, but whenever we do surveys, we find that those who wear lead have rates of workplace-related disease—specifically cervical and lumbar spine disease—that far exceeds those in any other manual labor out there. OSHA does studies on heavy-duty mechanics that show around 12% of employees have a level of workplace-related disease that requires operations and time off. When we look at IR or interventional cardiology, we see this in almost 30% of respondents. Yet, we all ignore it, because we’re goal directed.
The other concern is radiation. It’s easy to overlook because the effects are delayed for so long, and you don’t feel it—but again, we’re exposed to a lot of radiation. I’m passionate about this because when I started, much of what we did was diagnostic procedures, with therapeutics as a small part. Most of those procedures were short. Today, what we’re doing is virtually all treatments, and it’s not uncommon to have procedures where the radiation doses are 1 Gy or more. Some of my partners are doing several involved procedures a month where the doses are 1–4 Gy. One of my surgical colleagues, who is immensely talented, did a procedure recently where the dose was 7.5 Gy.
As a result, we have a disconnect between wanting to offer more to patients and the physical stress it puts on our bodies and safety. It’s a challenge to find how to mitigate this—and an opportunity for someone to try to solve it.
What are some other opportunities you see for the field of IR?
LM: Right now, everybody is talking about AI, especially generative AI. But AI can be used in several ways. When you think about it, radiologists are ideally set up to be data stewards for this new generation of technology. We are technically competent, have an understanding about the digitization of medicine, and understand the full clinical process. It’s a tremendous opportunity for us to affirm our place. In particular, one of the things we can do is use AI to quantify and demonstrate the immense value and capacity of IR, especially in real-world situations. Because of our skill sets, I think IR will be better poised to do that than a lot of other specialties.
