"The energy consumption varies very much by modality. So MRI is much higher than CT, and CT is much higher than ultrasound, and ultrasound is even higher than X-ray. So when you think about the imaging that we're doing, you really have to be mindful of that. I think we have a responsibility to start thinking about what we can do to minimize that. 

Hanneman has been actively involved in studying the carbon footprint of radiology and advocating for more sustainable practices. Reducing energy consumption can also be a way for health systems to save on expenses. Just powering down imaging systems when not in use overnight, for example, can help centers realize saving while also reducing their carbon footprint.

During her RSNA session, Hanneman collaborated with other radiology leaders to raise awareness about the environmental impact of radiology. The speakers addressed various aspects, including the link between climate change and human health, energy requirements in medical imaging, and the potential for regulations and standards to encourage sustainability efforts.

One notable point discussed in the session was the collaboration between healthcare providers and vendors in the pursuit of sustainability. Hanneman commended the efforts of vendors in finding ways to reduce their carbon footprints. An example of this was Phillips Healthcare announcing a partnership with Vanderbilt University Medical Center (VUMC) during RSNA that aims to reduce the health system’s radiology carbon footprint while determining a blueprint to help guide industry efforts. This includes developing a common language and metrics to measure and communicate greenhouse gas emission savings.

“We consider climate care as healthcare. Taking steps to reduce the carbon footprint in healthcare isn’t just an opportunity; it’s also a responsibility. The future of radiology requires us to be cognizant, aware and proactive about addressing this issue which directly affects the communities we live in and the patients we treat. We have a collective responsibility to help mitigate climate change, which is why we’ve entered into this collaboration,” explained Reed Omary, MD, MS, Carol D. and Henry P. Pendergrass professor and chair of radiology at VUMC in a statement about the collaboration. Omary was another speakers during the RSNA session. 

Radiology should be asking vendors more questions about scanner energy consumption

There has been many technological advancements in imaging systems, but often lower energy consumption is something ranked further down the list from image quality and features to aid patient throughput. But, imaging systems have become more energy-efficient with the development of better detectors that do not require as much X-ray radiation to create an image, the use of image reconstruction software and now artificial intelligence (AI) to enable diagnostic quality images from low-dose scans, the use of passive cooling systems to reduce the need for powered cooling systems and the use of device use data analytics and now AI to track power consumption.

Hanneman acknowledged that while some scanners have become more efficient, this has been offset by growing exam volumes and the increased use of higher field strength MRI systems.

Gathering data on power usage is something that will be critical in the future to understanding areas where improvements need to be made and when looking at usage trends on the machines. In many cases, this is data that is just not collected right now and you cannot change something if you do not have data to track trends. This was also true of radiation dose levels a decade ago were most CT scanners did not have dose tracking data turned on. 

"I think this is an area where AI might help us to identify a scanner has been idle for a certain amount of time and perhaps interfacing with patient scheduling for example, or knowing the time of day and understanding when to potentially power down ... This is really important and something that I think we have to engage with the vendors on," Hanneman said. 

She said some MRI vendors are working on creating "very low" power modes and AI algorithms might be able to predict when a scanner can dip in and out of this reduced energy state.

"I do think there's a lot of work that needs to be done, but I think there's a vast potential here," she explained. 

Hanneman urged radiologists to consider sustainability factors when evaluating and purchasing new equipment. Engaging with vendor partners during the request for proposal processes and incorporating sustainability metrics into decision-making processes can be essential steps in promoting a more eco-friendly approach to medical imaging.