Accessible magnetic resonance imaging: A review

Abstract

The role of MRI in diagnostics, prognostics, and discoveries in basic sciences has been well established. However, access to this life‐saving technology is largely restricted to countries in upper‐middle to high‐income groups. In this article, we collate recent global MR scanner density data and group them into six geographical regions based on the WHO classification. We then analyze these data with respect to demographic factors such as population size, life expectancy, the percentage of internet users, and World Bank income grouping. We map these demographic factors to five dimensions or characteristics of accessible MRI, adapting definitions from the healthcare literature. With this background, the study then reviews recent demonstrations of accessible MRI categorized based on main magnetic field strength. We describe demonstrated examples for each of these categories, ranging from ultralow‐field to ultrahigh‐field MRI. Lastly, we review MR methods and associated developments impacting accessible MRI such as increasing/augmenting MR awareness and local expertise, incorporating hardware‐cognizant methods, rapid quantitative imaging, and leveraging innovations from adjacent fields. Level of Evidence: 5 Technical Efficacy Stage: 6 J. Magn. Reson. Imaging 2019.

Assessment of cardiac function, blood flow and myocardial tissue relaxation parameters at 0.35 T

“…These results support the potential for low‐field MRI to expand cardiac MR availability to patients who may be contraindicated at higher B0, and increase accessibility in terms of lowered equipment costs. A lower cost, low field strength system with modern gradient and RF performance, and advanced iterative reconstruction methods capable of providing high quality diagnostic cardiac imaging, could have a profound impact on expanding the availability and accessibility of cardiac MRI services beyond academic medical centers in both developed and developing economies 71 …”

The MR Cap: A single‐sided MRI system designed for potential point‐of‐care limited field‐of‐view brain imaging

“…In addition to extending MRI applications to point‐of‐care sites, significantly reducing the equipment and siting costs of an MRI scanner might extend the impact of MRI diagnostic techniques, even if the scanner had a narrow clinical focus. As discussed in the Introduction, there is precedent for this in other imaging modalities, and there are large sections of the Global South and Global North with relatively sparse access to MRI …”

“…Recent reviews have examined the development of portable and low‐cost MRI systems for brain imaging . These include ultralow field systems that attempt to reduce cost and weight by reducing B 0 below 10 mT; prepolarized systems; low‐field systems employing resistive magnets or permanent magnet arrays, potentially employing built‐in encoding fields; and high‐ field systems with reduced cryogen use or new superconductor or cryostat technology .…”

Virtual Scanner: MRI on a Browser

“…The Standard Mode mimics a real scanner console and enables the user to perform custom MRI experiments. This mode may be used by MRI technicians as practice for scanner console operation without requiring expensive scanner hours and can help increase access to education (Geethanath & Vaughan Jr, 2019).…”