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arXiv · 2203.03455

Portable magnetic resonance imaging of patients indoors, outdoors and at home

T. Guallart-Naval·J. M. Algarín·R. Pellicer-Guridi·F. Galve·Y. Vives-Gilabert·R. Bosch·E. Pallás·J. M. González·J. P. Rigla·P. Martínez·F. J. Lloris·J. Borreguero·A. Marcos-Perucho·V. Negnevitsky·L. Martí-Bonmatí·A. Ríos·J. M. Benlloch·J. Alonso
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Abstract

Mobile medical imaging devices are invaluable for clinical diagnostic purposes both in and outside healthcare institutions. Among the various imaging modalities, only a few are readily portable. Magnetic resonance imaging (MRI), the gold standard for numerous healthcare conditions, does not traditionally belong to this group. Recently, low-field MRI start-up companies have demonstrated the first decisive steps towards portability within medical facilities, but these are so far incompatible with more demanding use cases such as in remote and developing regions, sports facilities and events, medical and military camps, or home healthcare. Here we present in vivo images taken with a light, home-made, low-field extremity MRI scanner outside the controlled environment provided by medical facilities. To demonstrate the true portability of the system and benchmark its performance in various relevant scenarios, we have acquired images of a volunteer's knee in: i) an MRI physics laboratory; ii) an office room; iii) outside a campus building, connected to a nearby power outlet; iv) in open air, powered from a small fuel-based generator; and v) at the volunteer's home. All images have been acquired within clinically viable times, and signal-to-noise ratios (SNR) and tissue contrast suffice for 2D and 3D reconstructions with diagnostic value, with comparable overall image quality across all five situations. Furthermore, the volunteer carries a fixation metallic implant screwed to the femur, which leads to strong artifacts in standard clinical systems but appears sharp in our low-field acquisitions. Altogether, this work opens a path towards highly accessible MRI under circumstances previously unrealistic.

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T. Guallart-Naval, J. M. Algarín, R. Pellicer-Guridi, F. Galve, Y. Vives-Gilabert, R. Bosch, E. Pallás, J. M. González, J. P. Rigla, P. Martínez, F. J. Lloris, J. Borreguero, A. Marcos-Perucho, V. Negnevitsky, L. Martí-Bonmatí, A. Ríos, J. M. Benlloch, J. Alonso. 2023-02-15. Portable magnetic resonance imaging of patients indoors, outdoors and at home. https://doi.org/10.1038/s41598-022-17472-w

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