Patient Information


Meet James F. Dempsey, PhD
Inventor, Founder, and Chief Scientific Officer of ViewRay

Much like the ViewRay technology that he invented, Jim Dempsey adapts. He follows his curiosity, looks at the variables around him and takes note of what he’s good at – from playing lead guitar in a heavy metal band to deciphering physics and chemistry problems. Science, and the influence of his mentors, shaped the path of his career.

James Dempsey, PhD Inventor, Founder and CSO of ViewRay alongside a MRIdian system

Pictured here is James Dempsey, PhD Inventor, Founder and CSO of ViewRay alongside a MRIdian system

“I told my father that I was going to be a rockstar so that I did not need to go to college. He told me that rockstars either got a job or went to college,” he recalls. “So I decided to go to college.”

Entering college at San José State University in California, Jim took physics and math, and majored in radiochemistry, discovering that, “I just had a knack for solving physical problems.”

Like many of us who appreciate a mentor’s words, Jim says, “I met Professor Peter A.J. Englert at San José State University and he was the real life Indiana Jones of science. He convinced me to be a scientist. I signed up to work for him and followed him to nuclear science labs all over the world from Los Alamos National Lab to the Cosmo-chemistry Department of the Max Planck Institute for Chemistry in Mainz, Germany.”

Next Jim attended Washington University in St. Louis, MO to obtain his M.S. and his Ph.D. in Nuclear Chemistry. There Jim worked on the fragmentation of hot nuclear matter finishing his graduate work in just three and a half years. “It was a fascinating topic, but had no immediate practical application.”

Throughout his graduate research work, Jim excelled in the nuclear physics field, but he became disillusioned and sought new opportunities where he could be closer to the science. A friend and recent nuclear physicist graduate, Dr. Assen Kirov (now at Memorial Sloan Kettering Cancer Center), had recently joined the medical school at Washington University in St. Louis and suggested that Jim look into joining the medical physics team there.

Jim toured the radiation therapy department and met with many scientists who impressed him. During the tour they happened to pass through the radiation therapy waiting room. “I didn’t know anything about medicine. … I never knew that a physicist would be in a hospital, but I went to this waiting room and I saw all of these people being treated for cancer, it was horrifying,” he says. “I could sense their fear, their doubt, their need…” It was right then that Jim knew what would become his life’s work: Employ the science of fundamental physics and chemistry to perfect the treatment of cancer.

Early on he concluded that a big problem needed to be solved:  How can clinicians see a tumor during treatment to ensure that the dose is actually hitting the tumor and not the healthy tissues and critical organs that move constantly around it?

“I didn’t have any personal experience with cancer, but as a scientist, I realized there was another level to problem solving. It’s not enough to just find the problem and solve it before everybody else. What if you had to find one that mattered? The one that truly helped somebody. It had never dawned on me before that I could really help someone this way.”

Jim then switched fields from nuclear physics and chemistry to medical physics, going through a postdoctoral research program and a medical physics residency program at Washington University. Upon graduating from the residency program he moved to the University of Florida (UF) where he developed a successful and well-funded research lab.

Jim founded ViewRay in 2004 while working at UF, which had a top technology transfer program lead by David Day and was tremendously supportive of faculty founding companies and licensing technologies. During that time, Jim worked at

ViewRay on his personal time off and many of his fellow UF faculty and colleagues who also shared his dream were early research collaborators, supporters, and investors in the company. Four years later in 2008, when Jim was an associate professor of radiation oncology and nuclear engineering at UF, he resigned from his tenured faculty position to focus exclusively on ViewRay.

Jim shared, “Although I was very successful in grant funding, lecturing, and manuscript publishing, I wasn’t making a truly significant impact on clinical practice. I still hadn’t really helped those poor patients in the waiting room.”

Jim was determined to overcome the key limitations of existing radiation therapy machines, which use X-ray based imaging technology that can’t accurately visualize a tumor and its position in relation to nearby critical structures. Jim sought out to integrate the best imaging technique in medicine, magnetic resonance imaging (MRI). MRI was widely used for diagnostic purposes for its ability to distinguish soft tissues clearly and could image without dosing or affecting the patient, but MRI had previously been considered incompatible with radiation therapy. Jim knew that physicians needed to see the tumor, soft tissues, and healthy organs to ensure that the dose of radiation therapy could be reshaped or adapted to changes taking place inside the body and to watch the tissue while the beam is on so it would never miss.

Jim recognized that great science must be collaborative and it must change the paradigm. Jim says that, “If you have a dream and you want it to come true, you must share your dream. ViewRay is about sharing the dream.”

ViewRay assembled a world-class team of scientists and engineers to develop the MRIdian system, which received FDA clearance in 2012 and treated its first patients in early 2014. In 2016 the next generation system, a linear accelerator based device, was unveiled. The new system, MRIdian Linac, received the CE Mark in Europe in 2016 and FDA-clearance in the United States in early 2017.

“So, the whole thing was a long way to come for a rockstar, right?” says Jim. “When you find something you like that you really feel you were destined to do, you feel as if everything in your life – every experience and the path you took to get there – really makes sense. Nearly all of us at ViewRay share that feeling.”

“At ViewRay, we have an innovation and science team that invents new products and features. They are an amazing, world-class team of scientists and engineers. We never ask ‘Can we do it?’ We are fearless, dauntless. We do it. It’s our job, right? Hey, here’s an impossible problem, let’s go solve it. We have worked hard to develop a process that integrates science, engineering, quality, manufacturing, and other process driven teams we need to collaborate with in order to make great products. Nobody else does that.”

* Required

Subscribe to: Patient Information Newsletter


Copyright 2017 © ViewRay. All rights reserved - KMCreative