How Medical Imaging Is Going Green: The Breakthroughs Shaping a Cleaner, Smarter Future

Over the last few years, sustainability has moved from a side conversation to a central concern in medical imaging. Radiology, nuclear medicine, and radiotherapy departments are now being asked not only to deliver accurate diagnosis and treatment, but also to support net-zero strategies, protect water systems, and use digital resources more wisely.

What has changed is that we now have better numbers, clearer frameworks and a much more practical sense of what a “greener” imaging service actually looks like. This article walks through the main developments and what they mean in real clinical practice.

Measuring the footprint of imaging – from guesswork to data

For a long time, discussions about sustainability in imaging were based on intuition: MRI “feels” energy hungry, CT “must be bad for the planet”, PACS “probably uses a lot of storage”. Recent life-cycle assessments have begun to quantify this properly.

Studies examining emissions over a decade of radiology department activity show that the largest share of carbon emissions comes from electricity used by scanners, cooling systems, and workstations. MRI tends to have the highest emissions per examination, followed by CT, with ultrasound and plain radiography at the lower end. Non-productive time is a major culprit: scanners sitting idle, cooled and powered, outside core scanning hours.

This shift from rough estimates to empirical data has changed the conversation. Departments can now point to baseline figures, model the effect of interventions and set realistic targets. Sustainability has started to look less like an abstract ideal and more like a quality improvement project that can be measured, audited and refined.

Energy-efficient scanners and smarter use of power

One of the clearest areas of progress has been energy management. Manufacturers are designing scanners with lower energy consumption per scan, innovative standby modes and better integration with building systems. At the same time, hospitals are modifying how they operate those systems day to day.

Standard measures include powering down scanners fully overnight rather than leaving them in high-energy idle states; scheduling lists to reduce gaps during which equipment is on but unused; and rationalising the number of image review workstations that remain active out of hours. Some centres are experimenting with on-site renewable energy, such as rooftop solar, to supply a portion of the electricity used by MRI and CT.

All of this is supported by better metering. Instead of assuming that “imaging uses a lot of power”, departments are installing sub-meters on scanner rooms and PACS racks to see where electricity is actually going. That enables targeted actions, such as adjusting room set points for air conditioning or swapping older, inefficient hardware for modern, lower-power alternatives.

Contrast media and the environment – from blind spot to priority

One of the most striking developments is the growing awareness of how contrast agents behave after leaving the hospital. Iodinated contrast media used for CT and gadolinium-based contrast agents (GBCAs) used for MRI pass through the body largely unchanged and enter wastewater. Conventional treatment plants do not remove them effectively, so they can be detected downstream in rivers, lakes, and even drinking water sources.

Environmental and toxicological studies have now documented anthropogenic gadolinium signatures in surface waters, linked to medical MRI use. Similar concerns are being raised about iodinated agents, both for ecological impact and for their contribution to the overall chemical burden in aquatic systems.

In response, contrast stewardship is broadening. The emphasis remains on patient safety and diagnostic yield, with an added environmental dimension. Practical steps include tighter indications for contrast use, protocol review to reduce unnecessary enhanced series, dose optimisation based on body habitus and renal function, and a preference for macrocyclic gadolinium agents when clinically suitable.

A handful of centres are piloting urine collection systems for high-volume contrast use scenarios, such as interventional suites or chemotherapy day units, coupled with emerging technologies to capture or degrade contrast before discharge to sewer. These projects are still early, but they signal a shift: contrast agents are no longer seen as harmless once they have served their diagnostic purpose.

Choosing the right test – clinical value and carbon hand in hand

Appropriateness of imaging is hardly a new topic, but it now carries a clear environmental rationale. Every examination has an associated carbon cost, material use and data footprint. Reducing low-value imaging is therefore one of the most effective routes to greener practice.

Decision support tools integrated into electronic requesting systems are being framed not only as safety and efficiency measures, but also as sustainability interventions. If a clinician is nudged towards an ultrasound instead of a CT, or away from a repeat MRI that will not change management, there is an environmental benefit as well as a clinical one.

Guidelines and campaigns that encourage “doing the right test at the right time” are beginning to include carbon considerations explicitly. Pathways for conditions such as suspected renal colic, appendicitis or minor head injury are being revisited with energy use in mind, promoting ultrasound or plain radiography as first-line tests where evidence permits, and reserving CT and MRI for cases where their additional value is clear.

In radiotherapy and interventional radiology, teams are reviewing how often imaging is used for planning, verification and follow-up. Reducing unnecessary scanning in these settings can cut both radiation dose and emissions, without undermining safety.

Digital sustainability – PACS, archives and remote working

Medical imaging has been digital for years, but only recently has the environmental impact of data storage and transmission come under scrutiny. Datacentres and PACS servers consume electricity; redundant or unnecessary image series multiply that load.

A key development has been the recognition that post-processing in CT can create a large number of additional series that add little or nothing to clinical interpretation but must still be stored, backed up and sometimes migrated during system upgrades. Several studies have modelled the potential for reducing emissions by archiving only essential series or applying stricter retention policies for derived datasets.

Departments are also examining how long they retain certain image classes, whether they duplicate data across multiple systems, and whether compression and tiered storage could be used more aggressively without compromising clinical access or legal requirements.

Alongside storage, remote working has gained traction as a sustainability tool. Home reporting for radiologists and teleradiology within wider networks can reduce commuting and business travel, support flexible staffing, and, in some cases, allow a more rational distribution of workload across sites. Virtual multidisciplinary team meetings and remote teaching further reduce the need for staff travel, resulting in savings in fuel use and time.

The challenge is to balance these gains with the energy cost of extra network traffic and additional devices. Here again, measurement and benchmarking are key: knowing the power consumption of home workstations and VPN infrastructure enables evaluation of whether a given arrangement is genuinely beneficial overall.

AI as both helper and burden

Artificial intelligence is now deeply embedded in discussions about the future of radiology and nuclear medicine. Sustainability is part of that conversation, and it cuts both ways.

On the positive side, AI can help reduce the number of scans performed or the dose and duration of those scans. Examples include algorithms that denoise low-dose CT or PET images, enabling shorter acquisitions or lower radioisotope activity; triage tools that prioritise time-sensitive findings and may reduce unnecessary repeat imaging; and decision support systems that guide referrers towards the most appropriate modality and protocol.

AI can also streamline workflows, reducing patient length of stay and preventing missed follow-ups, thereby providing indirect environmental benefits through better resource use.

However, training and running AI models use significant computing power, especially for large deep learning networks and centralised cloud-based systems. There is growing pressure on developers and vendors to disclose the energy and carbon costs of model training and inference, and to design architectures that are efficient as well as accurate.

The current direction of travel is towards “green AI”: models that are right-sized, trained with attention to energy use, and deployed in ways that demonstrably reduce the overall environmental impact of imaging pathways rather than adding a new layer of consumption.

Policies, frameworks and procurement: sustainability becomes mainstream

Perhaps the most important shift is cultural and organisational. Many health systems, including the NHS, now have formal net-zero commitments with target years and interim milestones. Within those strategies, imaging is increasingly visible as a specific workstream.

National bodies and professional societies are publishing position statements, checklists and action plans for “environmentally sustainable radiology” or “green radiotherapy”. These documents translate broad climate targets into concrete steps at the department level: energy audits, contrast stewardship committees, sustainable procurement criteria, waste segregation plans and staff education programmes.

Procurement is a key lever. When hospitals specify energy performance, recyclability, take-back schemes, refurbishment options and supplier emissions reporting as requirements for new imaging equipment, industry responds. Some manufacturers now provide emissions data for their devices and offer service packages that include efficiency optimisation and end-of-life management.

Importantly, sustainability is increasingly seen as part of quality and safety, rather than a separate agenda. A scan that is unnecessary, poorly indicated, or inefficiently delivered is now understood to be wasteful in environmental, clinical, and financial terms. That alignment makes it easier to integrate green initiatives into existing governance structures and improvement cycles.

What might a sustainable imaging department look like?

Putting these threads together, it is possible to sketch a picture of a modern imaging service with sustainability as a core principle.

Referral pathways are carefully designed so that the lowest-impact modality is used whenever clinically acceptable. Decision support in ordering systems helps referrers choose wisely, and feedback reports highlight patterns of overuse. Radiologists and radiographers are actively engaged in reviewing protocols and questioning legacy practices that add little value.

Scanners operate according to an energy-aware schedule, with clear rules for powering down, consolidating lists and managing idle time. Facilities teams monitor electricity use at a granular level and work with imaging staff to adjust cooling, ventilation and lighting without compromising safety or comfort.

Contrast use is tracked and optimised. Electronic records link contrast doses to indications and outcomes, allowing stewardship teams to refine protocols, compare agents and identify areas where contrast-enhanced imaging can be reduced. Pilot projects test methods to minimise environmental discharge of contrast, where feasible.

Digital systems are configured with sustainability in mind. Redundant series are not archived by default; storage tiers are used intelligently; and backup strategies are designed to be robust without unnecessary duplication. Remote reporting and virtual collaboration are part of normal practice, supported by secure, energy-efficient infrastructure.

Finally, sustainability is embedded in governance. Departmental dashboards include environmental indicators alongside waiting times and report turnaround times. New equipment and software are evaluated not only on price and performance, but also on life-cycle emissions and waste implications. Staff education covers climate, health and the environmental aspects of imaging, so that everyone understands why these changes matter.

Conclusion

Medical imaging has always been central to modern healthcare. As climate commitments tighten and awareness of environmental health grows, it cannot sit on the sidelines. The most recent developments show that sustainability is no longer a vague aspiration but an area where concrete, measurable progress is possible.

Better data on energy use and emissions, awareness of contrast media in the environment, smarter digital practices, thoughtful application of AI and strong policy signals are all pushing imaging departments in the same direction. The challenge now is to move from pilot projects and early adopters to widespread, routine practice.

For clinicians, physicists, radiographers and administrators, this offers an opportunity rather than a burden. Many of the changes that reduce emissions also improve efficiency, patient experience and clinical quality. A sustainable imaging service is, in many respects, simply a well-designed one that makes wise use of energy, materials, data and human effort.

Disclaimer

The information presented in How Medical Imaging Is Going Green: The Breakthroughs Shaping a Cleaner, Smarter Future is intended for general educational purposes and should not be interpreted as clinical guidance, regulatory instruction or a substitute for professional judgement. While every effort has been made to ensure accuracy at the time of publication, emerging research, evolving technologies and local policies may lead to differences in practice. Open MedScience accepts no liability for any decisions or actions taken based on the content of this article. Readers should consult appropriate clinical, technical and environmental experts, as well as relevant national and institutional guidelines, before implementing any strategies or making changes to imaging services. Any views expressed are those of the authors and do not necessarily reflect the position of healthcare organisations, manufacturers or professional bodies.