Long-term trends and projections of CT and MRI utilization across selected OECD countries: a framework for sustainable imaging service planning

Objectives CT and MRI utilization is increasing across high-income countries, partly because of population ageing. This study integrated cross-country trends in examination rates, demographic change, and scanner productivity across OECD countries to project utilization to 2050 and inform sustainable service planning. Materials and methods CT and MRI examination rates were obtained from the OECD Data Explorer and Japan’s National Database of Health Insurance Claims Open Data. Population data were derived from the United Nations World Population Prospects 2024. Linear regression projected examination rates to 2050. Pearson coefficients assessed associations between imaging rates and population shares aged 0–14, 15–64, and ≥ 65 years. Scanner productivity was calculated as annual examinations per device. Results CT utilization was strongly associated with the population aged ≥ 65 years in all countries (r = 0.95–1.00). MRI showed similarly strong associations in most countries (r = 0.95–0.99), with Italy as the main exception. Linear extrapolation projected CT rates of approximately 722 examinations per 1000 population in Korea and 520 in the United States by 2050, while MRI rates reached approximately 327 in France and 308 in Germany. Population-level utilization did not consistently correspond to device-level productivity; CT examinations per scanner ranged from 2153.3 in Japan to 11,526.5 in Canada. Conclusions Population ageing was associated with increasing CT and MRI utilization. Future demand may also depend on health system organization and scanner productivity. Sustainable planning should integrate demographic forecasting, appropriateness stewardship, operational optimization, workforce development, and technological innovation rather than rely solely on proportional capacity expansion. Key Points Question Ageing drives CT/MRI demand (r = 0.95–1.00 for CT); projected to continue to 2050, offering a valuable planning window. Findings High utilization ≠ high scanner productivity; operational organization shapes imaging output independently of demand volume. Critical relevance statement Sustainable planning requires demographic forecasting, appropriateness management, and technological innovation, not just capacity expansion.