INSTITUTE OF PHYSICS PUBLISHING MEASUREMENT SCIENCE AND TECHNOLOGY Meas. Sci. Technol. 16 (2005) R17–R36 doi:10.1088/0957-0233/16/4/R01 REVIEW ARTICLE In vivo magnetic resonance imaging: insights into structure and function of the central nervous system Oliver Natt and Jens Frahm Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut fur¨ biophysikalische Chemie, Am Faßberg 11, 37070 Gottingen,¨ Germany E-mail:
[email protected] Received 25 February 2004, in final form 22 November 2004 Published 24 February 2005 Online at stacks.iop.org/MST/16/R17 Abstract Spatially resolved nuclear magnetic resonance (NMR) techniques provide structural, metabolic and functional insights into the central nervous system and allow for repetitive in vivo studies of both humans and animals. Complementing its prominent role in diagnostic imaging, magnetic resonance imaging (MRI) has evolved into an indispensable research tool in system-oriented neurobiology where contributions to functional genomics and translational medicine bridge the gap from molecular biology to animal models and clinical applications. This review presents an overview on some of the most relevant advances in MRI. An introduction covering the basic principles is followed by a discussion of technological improvements in instrumentation and imaging sequences including recent developments in parallel acquisition techniques. Because MRI is noninvasive in contrast to most other imaging modalities, examples focus on in vivo studies of the central nervous system in a variety of species ranging from humans to mice and insects. Keywords: blood oxygenation level dependent (BOLD) contrast, central nervous system (CNS), diffusion, echo-planar imaging (EPI), fast low angle shot (FLASH), magnetic resonance angiography (MRA), magnetic resonance imaging (MRI), magnetization transfer (MT) contrast, nuclear magnetic resonance (NMR), partially parallel acquisition (PPA) (Some figures in this article are in colour only in the electronic version) 1.