Radiation sciences student offers a clearer image of risk for diabetes patients with CGMs

By John Battiston

A casual comment from a patient before an X-ray led Brittany Gundersen to dive into an intriguing issue in radiologic science.

Millions of Americans manage their diabetes with CGMs – continuous glucose monitors – that track blood sugar levels through the skin, without finger sticks. The sensors, typically worn on the arm or abdomen, contain tiny metallic components and electronic transmitters that could interact with common imaging modalities, including X-ray, CT and MRI.

“The patient mentioned that they needed to take off their Dexcom continuous glucose monitor because they’d been told they couldn’t wear one during X-rays,” said Gundersen, who at the time was working at the Orthopaedic & Spine Center of Newport News while pursuing her undergraduate degree in clinical radiation sciences in Virginia Commonwealth University’s College of Health Professions.

The comment struck Gundersen as odd: She wasn’t aware that CGMs had been established as devices that weren’t X-ray-friendly. Then a second patient mentioned removing their CGM before an X-ray.

“At this point, I became curious and wanted to make sure that our office was up to date on these devices,” Gundersen said.

That curiosity would ultimately lead Gundersen, who earned her degree in 2025, to devote her senior project in VCU’s Department of Radiation Sciences to studying the safety of wearing CGMs during diagnostic imaging. Under the guidance of department Chair Jeff Legg, Ph.D., her investigation culminated in a peer-reviewed paper recently in Radiologic Technology, exploring the intersection of medical imaging, radiation exposure and device integrity.

Gundersen’s research underscores the significance of the topic, in light of the prevalence of diabetes and advances in imaging.

In her study, Gundersen reviewed existing literature and manufacturer guidance across the three common modalities. She found that CGMs don’t encounter interference or pose safety concerns to patients undergoing X-ray or CT imaging. Though CGMs can cause artifacting or distortions on an X-ray or CT image, which can limit diagnostic information, the devices are still considered safe to wear during the procedure.

But the powerful magnetic fields and radiofrequency waves associated with MRI can heat up the metal components in a CGM and burn the wearer. MRI can also cause a CGM to malfunction and display inaccurate glucose levels.

Gundersen’s findings align with a 2021 Journal of Diabetes Science and Technology article, which found that Dexcom G6 CGMs maintained their data and functionality even under radiation exposures far higher than typical diagnostic levels. Yet Gundersen emphasizes that safety protocols must continue to err on the side of caution – particularly in MRI environments, where electromagnetic fields and heating pose real risks.

Her project was assigned as part of a three-course sequence designed to help students learn about the basics of research, develop critical thinking and communication skills, and delve deeper into a topic of interest. Gundersen’s paper reflects how the radiation sciences curriculum blends classroom theory with real-world problem-solving.

“Dr. Legg helped me immensely,” she said. “We came up with questions for me to answer myself during the research process, and with those, I steadily came up with new questions.”

Gundersen said the most meaningful outcome of her research has been applying what she learned directly to patient care. She is now a full-time radiographer at the Newport News center.

“I’m well-versed at explaining to the patient why they don’t need to remove their CGM for an X-ray vs. an MRI,” she said, adding that she is working with colleagues to ensure that schedulers educate patients about bringing extra sensors for scans that require removal.

Gundersen also has advice for future students tackling their own senior projects.

“Ask all the questions you need to be able to feel confident in your writing,” she said. “It may take longer to do it that way, but in doing so, I gained a deeper understanding of every part of this senior project.”

This story was originally published on the College of Health Professions website.