The Maestro of Medical Physics

Mahadevappa Mahesh, MS, PhD, FACR, a diagnostic medical imaging physicist and professor of radiology and radiological science at the Johns Hopkins University School of Medicine, currently serves as chair of the ACR Commission on Medical Physics, as well as the JACR^® associate editor of physics. Mahesh was recently elected to the president track for the American Association of Physicists in Medicine (AAPM), where he served as treasurer from 2016 to 2021. He will serve as president-elect of the AAPM in 2024, president in 2025 and board chair in 2026. 

The Bulletin sat down with Mahesh to discuss the election results, the evolution of the field of medical physics, and how radiologists and medical physicists can work together to improve the practice of radiology.

How did you become a medical physicist? What attracted you to your specialty?

Medical physics was an accidental discovery for me. When I was in graduate school at Marquette University in Wisconsin, where I was obtaining my master’s degree in physics. I came across an open house at the Medical College of Wisconsin focusing on medical physics, and it was a new field that sounded very exciting because it’s very much application-oriented physics compared to other physics fields. When I applied to the doctorate program in medical physics at the Medical College of Wisconsin, I was awarded a full research scholarship. And that’s how I ended up in medical physics.

You’ve been a medical physicist for more than 30 years. How have the fields of radiology and medical physics evolved over your years of practice?

The fields of radiology and medical physics have really grown by leaps and bounds. For example, CT was already advanced and routinely used when I was in graduate school, but it was only doing one single-slice acquisition. Around 1998, there was a major evolution of the CT technology called multidetector CT (MDCT) that, within a matter of 10 years or so, opened the field expansively. A lot of new areas emerged because of that multidetector CT technology — to name a few: cardiac CT, which was not a field at all in the past, PET-CT (hybrid imaging), CT perfusion and so on. So several technological advances in the past 30 years have really changed things, even though the fundamental physics remains the same. 

You recently were named president of the AAPM. What plans do you have for your presidency? Are there any AAPM initiatives you’re especially passionate about?

I've been very fortunate because I have been with AAPM for a long time. Throughout my time with the association, I have served as newsletter editor, board member and treasurer, to name a just few roles. 

I have several plans in mind. One thing I would like to do is further enhance the relationship between imaging physicists and radiation therapy physicists so they can work more closely and collaboratively. The second thing I want to do is promote the field of medical physics to other medical disciplines outside of radiology and radiation oncology. In addition, since I'm involved with several international organizations in the field, including the International Organization of Medical Physics and the International Atomic Energy Agency, I want to use my position to further strengthen the relationships between the AAPM and other medical physics-related organizations. It’s particularly important to me that we provide ample support to organizations working in low- and middle-income regions, where there is a significant need for education and training in the fields of medical physics and radiology. My hope is to help these organizations promote the profession of medical physics in their home countries.

In addition to your involvement with the AAPM, you also serve on the ACR BOC. How has your work with the College influenced the field of medical physics? How do you see your many leadership roles influencing each other? 

From the beginning of my career, I have admired what the ACR has done for the field of medical physics. The ACR has always recognized that imaging is well-served by the teamwork of radiologists, medical physicists and radiographers. Although the ACR’s membership is predominantly composed of radiologists, we have about 1,000 medical physics members. As chair of the ACR Commission on Medical Physics, I get to represent these members on the ACR BOC.

I like to share as an example of how ACR supports medical physics the College’s advocacy for mammography regulation. The ACR fought for legislation requiring mammography systems to be tested annually by a qualified medical physicist. The College worked with the FDA in drafting the Mammography Quality Standard Act (MQSA) OF 1994, cementing the status of medical physicists as essential members of any medical imaging team. The ACR’s work toward the passage of the MQSA paved the way for other crucial quality and safety regulation requirements mandating medical physicists’ involvement. As a medical physicist and as an ACR member, I have participated in many Capitol Hill visits advocating for radiology and medical physics issues. I hope to continue this advocacy through my leadership of the AAPM as well.

You work with both medical physicists and radiologists daily. What are some ways medical physicists and radiologists can collaborate to advance the field of imaging?

One of the ways we are already collaborating is that all the technical standards published by the ACR are published with the collaboration of the AAPM. When it comes to technical standards, the ACR has always recognized the role of the medical physicist. Therefore, all technical standards and guidelines are issued jointly. Another area of collaboration is exploring the use of AI tools. Medical physicists and the AAPM can work with our ACR colleagues to develop quality control methods to evaluate AI biases and ensure objectivity. 

What advice do you have for fellow practitioners looking to take on leadership roles in the medical physics and radiology communities?

In general, what I tell anybody who’s interested in leadership is that they need to keep an open mind in the sense that they need to learn as much as possible about what’s out there in the field. These days, it is very easy for younger professionals to do this because of technology. Information is at their fingertips. I also advise everyone, whether they’re a radiologist or a medical physicist, to be courteous and kind, because that goes a long way not only with your peers, but also with others. Whether you’re with patients, staff or administrators, being courteous is essential. Having a positive attitude is especially important in these days of high stress and isolation. When you treat people with kindness, they’ll be there for you when you need them most.