Ultra High Field Magnetic Resonance Imaging

From the early examples of what was to be called MRI, extending the te- nique to higher fields than those of less than 0. 1 T used in the first large-volume instruments was a goal, but the way there was unclear. The practical success of large superconducting magnets was a surprise, and the astonishment continued as they developed fields from 0. 3 T to 0. 6 T to 1. 5 T, and even more, up to the now common 3T systems, and a few 4T machines, and now to about 100 times the fields used in the first medium- and large-bore devices. In the early machines, low radiofrequencies of 4 MHz or so meant that RF coil designs were simple (even inexperienced undergraduates could design and build such circuits with little knowledge of more than DC electrical circuits), and the forces on gradient coils were small. The effects of magnetic susceptibility in- mogeneity in and around the object being imaged were negligible, and RF penet- tion depths were not a problem for human-scale samples. Everything began to change as higher fields and higher frequencies came into use, and the earlier idyllic simplicities began to seem quaint. The trend continued, however, driven by the increased signal-to-noise ratios and the resultant higher resolutions and speed available, and sophisticated engineering became more and more essential, not only for magnets but for gradient systems and radiofrequency transmitters and receivers, but also for better software for modeling and correcting distortions.

The up-to-date latest volume in the Biological Magnetic Resonance series

Klappentext
Ultra High Field Magnetic Resonance Imaging Prof. Pierre-Marie Robitaille, The Ohio State University Prof. Lawrence J. Berliner, University of Denver Ultra High Field Magnetic Resonance Imaging (UHFMRI) has undergone tremendous growth since its introduction in the late 1990's. Within a few years, it is anticipated that no less than 50 UHFMRI instruments will be in operation. The phenomenal growth of this modality has been driven in large measure by the tremendous signal to noise available with Ultra High Fields. Many challenges remain in order to bring UHFMRI into the mainstream of radiological diagnostic techniques. Nonetheless, with ground-breaking applications, UHFMRI is destined to promote great advancements in clinical medicine. Ultra High Field Magnetic Resonance Imaging covers the theoretical, experimental and clinical aspects of UHFMRI, and examines both its advantages and technical hurdles. Ultra High Field Magnetic Resonance Imaging is an invitation to the new generation of MRI scientists to invest in the wonderful modality which is UHFMRI. Key Features: Forward by Paul C. Lauterbur, University of Illinois, 2003 Nobel Prize in Medicine for Discoveries in Magnetic Resonance Imaging Historical Overview of Ultra High Field Magnetic Resonance Imaging Extensive Discussions of all Engineering Aspects of UHFMRI Including Magnet Design and Construction, Gradient Technology, Shim Coils and Ancillary Hardware. Presentation of System Sitting Considerations. Experimental and Theoretical Aspects of RF Coil Design for Ultra High Fields. Insight into Magnetic Susceptibility and UHFMRI Applications Including fMRI, Spectroscopy, Microscopy and High ResolutionImaging. Clinical Imaging with Particular Emphasis on Stroke and Tumor Evaluation. About the Editors: Dr. Pierre-Marie Robitaille is a Professor of Radiology at The Ohio State University. He has extensive experience in MRI and was responsible for the design and assembly of the first UHFMRI system. Dr. Lawrence J. Berliner is currently Professor and Chair of the Department of Chemistry and Biochemistry at the University of Denver. Dr. Berliner retired from Ohio State University where he spent a 32-year career in the area of biological magnetic resonance (EPR and NMR). He is the Series Editor for Biological Magnetic Resonance which was launched in 1979.

Inhalt
Ultra High Field Magnetic Resonance Imaging: A Historical Perspective.- Design Considerations for Ultra High Field MRI Magnet Systems.- Hardware Considerations in Ultra High Field MRI.- Aspects of Clinical Imaging at 7 T.- The Challenges of Integrating A 9.4T MR Scanner for Human Brain Imaging.- Ultra High Field MRI: High-Frequency Coils.- A Perspective into Ultra High Field MRI RF Coils.- Radiofrequency Field Calculations for High Field MRI.- Magnetic Susceptibility Effects in High Field MRI.- High Magnetic Fields for Imaging Cerebral Morphology, Function, and Biochemistry.- High-Resolution and Microscopic Imaging at High Field.- In-Vivo NMR Spectroscopy of the Brain at High Fields.- Clinical Promise: Clinical Imaging at Ultra High Field.