About Magnus

The MAGNUS (Microstructure Anatomy Gradient for Neuroimaging with Ultrafast Scanning) system was developed by GE under a contract from the US Department of Defense, with the goal of imaging the microstructure of the human brain at very high resolution.  This system is based on a unique head-only insert that is installed in a standard clinical 3T magnet; the narrower bore at the head allows the MAGNUS to achieve substantially higher gradient performance (measured by amplitude and slew rate) than the most advanced commercial systems such as the Siemens Prisma or 7T scanners. The only comparable scanner in the Boston area is the ‘Connectom’ at MGH Charlestown, with amplitude 300 mT/m and maximum slew rate 200 T/m/s, compared to the MAGNUS, which currently achieves 200 mT/m and 500 T/m/s (published) and is expected to achieve at least 250 mT/m and 700 T/m/s.

The high gradient performance of the MAGNUS translates to a more than 4-fold improvement over existing 3T scanners, shortening scan times and revealing details of brain microstructure that are undetectable on other 3T or even 7T scanners.  We expect to achieve even higher performance in future, through further upgrades to the gradient driver electronics, along with a novel 64-channel head coil that will be developed by Nova Medical as part of this project. 

The head-only design of the MAGNUS also minimizes the problem of cardiac and peripheral nerve stimulation, which has limited the performance of other advanced scanners. The MAGNUS design has additional advantages, including a wide bore, enabling scans of large or claustrophobic subjects who often cannot tolerate the narrow bore of a typical 3T scanner or an even narrower 7T scanner.

The first MAGNUS was installed in 2020 at Walter Reed National Military Medical Center in Bethesda, MD, where it is used to study traumatic brain injury in military personnel.  Other installations are planned at the University of Wisconsin-Madison and the University of Iowa. Installing this exceptional system at Brigham and Women’s Hospital will make it accessible to a large community of Boston-area researchers, and we anticipate that it will stimulate many new innovations and discoveries in basic and clinical neuroscience.

References:

Foo TKF et al. (2020) Highly efficient head-only magnetic field insert gradient coil for achieving simultaneous high gradient amplitude and slew rate at 3.0T (MAGNUS) for brain microstructure imaging.  Magn Reson Med 2020 Jun;83(6):2356-2369. [Pubmed]

Tan ET et al. (2020a) Peripheral nerve stimulation limits of a high amplitude and slew rate magnetic field gradient coil for neuroimaging. Magn Reson Med 2020 Jan;83(1):352-366. [Pubmed]

Tan ET et al. (2020b) Oscillating diffusion-encoding with a high gradient-amplitude and high slew-rate head-only gradient for human brain imaging. Magn Reson Med 2020 Aug;84(2):950-965. [Pubmed]