Project Summary/Abstract. This S10 High-End Instrumentation grant application from Washington University (WU) in St. Louis requests funds in partial support of the purchase of a Siemens whole-body human 7-T MRI scanner (MAGNETOM-Terra). Compared to a 3-T scanner, the 7-T MAGNETOM Terra provides twice the 1H MR signal-to-noise ratio (SNR). The increased SNR can be leveraged to provide (i) increased spatial resolution or (ii) more accurate voxel-wise estimation of signal amplitude. Magnetic susceptibility effects scale as the field strength, thus BOLD fMRI can achieve submillimeter resolution and susceptibility-weighted MRI at 7 T demonstrates substantially improved definition of tissue microstructure. There are no whole-body human 7-T MRI scanners at WU. The nearest whole-body human 7-T MRI scanners in the Midwest “St. Louis” region are found at considerable distance from the WU Medical Center, specifically, at the University of Missouri’s Columbia campus, 120 miles (2 hours by car), and at the Carle Foundation Hospital in Urbana, Illinois, 190 miles (3 hours by car). The requested 7-T human research scanner will join five Siemens 3-T workhorse research MRI instruments within the Mallinckrodt Institute of Radiology’s (MIR) Division of Research Imaging Facilities (RIF). The 7-T scanner will operate as part of MIR’s East Imaging Building “MRI Facility”, which manages three Siemens PRISMA 3-T MRI scanners. These MRI scanners are dedicated to clinical and nonclinical research involving outpatients and healthy control subjects, with a strong focus on brain imaging. MIR’s 3-T scanners are heavily utilized, logging an average of 1,630 billable hours per scanner (not including protocol development and maintenance time) in calendar year 2019 prior to COVID-related quarantine restrictions. As part of this S10 grant application, “base grant” summaries are provided for 29 NIH funded projects that will substantially benefit from the human 7-T research scanner. These base grants are heavily weighted toward neurology (brain) applications. Importantly, the requested 7-T scanner will anchor initiation of a major new research program in high-field MRI at WU. Toward this end, Richard Wahl, Radiology Chair and MIR Director, has made substantial financial commitments to ensure the success of the new research program. These commitments include: (i) ~$6,500,000 in “matching funds”, which added to a prospective $2,000,000 in funding from this S10 grant will equal the instrument’s purchase price of ~$8,500,000, (ii) $2,500,000 in renovation/construction costs to build a new scanner bay, which will enable siting of the 7-T scanner in the East Imaging Building, (iii) $1,400,000 to guarantee a Siemens service agreement throughout the first five years of scanner operation, and (iv) $2,500,000 to recruit two tenure-track/tenured high-field MRI faculty members, one focused on RF coils and other hardware issues and one focused on pulse-sequence design and image reconstruction algorithms. The institutional commitment to support the 7-T scanner and the development of a high-field MRI research program is truly outstanding.

Project Narrative: Ultra-high magnetic field strength MRI scanners offer significant benefits for research- focused imaging of human subjects, especially for neurology (brain) applications. Washington University in St. Louis hosts an extraordinary neuroscience imaging community of internationally respected scientists. This proposal from Washington University requests funding in partial support of the purchase of a ultra-high field, 7- tesla, human MRI scanner.