Color MRI on the horizon

Researchers in the USA have developed an approach to bring color to magnetic resonance imaging (MRI). The work, published in Nature this week, is expected to overcome the limitation of relying on ‘grey-scale’ contrast agents in MRI, which is widely used in medicine as a clinical diagnostic and biomedical research tool.

Gary Zabow and his colleagues from the National Institutes of Health in Bethesda, Maryland, and National Institute of Standards and Technology in Boulder, Colorado, microfabricated a family of magnetic microstructures that yield well-defined spectral signatures in the radio-frequency spectrum used for MRI — effectively giving them characteristic colors that can be readily distinguished from one another. Currently, the effects of contrast agents in MRI are largely indistinguishable from one another, leading to essentially monochrome contrast.

The microstructures also function as subcellular-sized spectral radio-frequency tags that enable increased MRI functionality, high sensitivity and greatly extended spectral ranges.

Commenting in a related ‘News and Views’ article, Richard Bowtell of the University of Nottingham’s Sir Peter Mansfield Magnetic Resonance Centre in the UK notes that the controlled spectral signatures provided by the microfabricated particles can be used immediately in various applications including cell tracking and microfluidics. “But the ultimate usefulness of these agents in vivo,” he says, “will probably depend on the feasibility of making magnetizable particles sensitive to physiological conditions.”