Environmental impact of portable MRI in remote Canadian settings

Background: Patients in remote communities often lack access to magnetic resonance imaging (MRI), necessitating long-distance transfers to tertiary centres for neuroimaging. Portable MRI (pMRI) addresses this gap by enabling bedside imaging without conventional scanner infrastructure. Its environmental profile, including energy consumption, patient transportation, and waste generation, compared with fixed MRI systems has not been comprehensively quantified in the literature.

Methods: We conducted a mixed-methods analysis of an ultra-low-field pMRI scanner, focusing on three domains: (i) energy consumption, (ii) transportation-related greenhouse gas (GHG) emissions, and (iii) waste generation. Published data on energy use and emissions from 1.5 Tesla (T) and 3 T scanners were compared with modelled estimates for pMRI. Transportation emissions were calculated for patient travel between Weeneebayko General Hospital (Moose Factory, Ontario) and Kingston Health Sciences Centre (Kingston, Ontario) using commercial, charter, and air ambulance flights. Waste-related emissions were assessed based on shielding materials, helium consumption, and gadolinium-based contrast agent use.

Results: pMRI consumed 11.8–17.4-fold less energy per scan than fixed 1.5 T and 3 T systems, corresponding to approximately 0.065 tons (t) CO₂ annually in a modelled 100–scan/year scenario. Based on published estimates, 56% of patients could avoid inter-facility transfer, which is estimated to reduce 14.3 t CO₂ emissions per year, equivalent to emissions from ~1.9 single-family homes. Waste analyses demonstrated that pMRI eliminated helium use, reduced shielding requirements, and minimized contrast-related waste, together preventing an additional ~5.4–9.8 t CO₂ per scanner over its lifecycle, which was equivalent to emissions produced by ~0.73–1.3 homes annually. This conservatively equates to a total carbon emissions reduction of 19.7–24.3 t per year or 2.6–3.1 home equivalents per year with pMRI implementation.

Conclusion: In a remote Canadian setting, pMRI provided local neuroimaging access to a predominantly Indigenous population, with 56% of patients avoiding inter-facility transfer while maintaining diagnostic quality. These clinical benefits were accompanied by a markedly reduced carbon footprint, supporting pMRI as both a health-equity intervention and a sustainable imaging strategy for underserved, remote regions.