NexGen 7T MRI scanner for mesoscale brain imaging: Integration and Dissemination

点击翻译按钮获取中文摘要

SUMMARY The "NexGen" 7 Tesla MRI scanner at UC Berkeley is a unique resource that we wish to make available for neuroscience collaborations across the globe. It was specifically designed for extremely high resolution structural and functional neuroimaging at the scale of cortical laminae and columnar neurocircuit organization ("meso-scale"). To achieve this, the NexGen scanner builds upon existing standard 7T scanners and integrates a number of technological advances, creating synergistic improvements and gains in speed, resolution and signal. Such advances include: currently the highest performance one-of-a-kind head-only magnetic gradient coil designed to safely create more signal at faster time scales (higher gradient amplitudes and slew rates without peripheral nerve stimulation; PNS), high-density receiver array coils (e.g. up to 128 channel receive array integrated into a 7T) that enable unprecedented spatial resolution and image-forming accelerations. As part of this collaborative endeavor, we will be creating novel advances in pulse sequences for novel neuroscientific applications imaging to take advantage of the scanner hardware’s higher performance. The scanner has been validated in reproducible mesoscale fMRI studies using GE-EPI and VASO fMRI at isotropic resolutions between 0.39 mm and 0.6 mm, that is a 4.6 to 23-fold higher volumetric resolution over typical 1 mm isotropic resolution in fMRI on conventional 7T scanners. The stronger gradients offer considerable improvements in diffusion imaging reaching higher b-values with shortened TEs. These hardware advances also enable larger areas of brain coverage, higher temporal resolutions and reduced distortions at mesoscale resolutions. Thus, with the NexGen 7T, meso-scale neuroscience experiments can be greatly expanded from traditional zoomed, small volume imaging approaches. Such a one-of-a-kind instrument has great potential to continue to advance the field and will be optimally used by a diverse group of neuroscientists and clinician scientists. Funding of the current U24 proposal would facilitate engineering and scientific personnel to support and maintain the use of the scanner; enables efficient data transfer and analysis, as well as the subject recruitment, user training and guidance of scientific collaborations nationally and internationally. While the main goal of this project is to provide an innovative resource for higher granularity in functional and structural human brain research, the research resource also holds potential for better understanding neurological diseases, such as Epilepsy, Alzheimer’s and mental disorders.