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 +To get the basic idea of CEST here a list of recent reviews. Best to for beginners is maybe
 +Chemical exchange saturation transfer (CEST): what is in a name and what isn't? by Peter van Zijl and NirbhayYadav.
 +Here the list of reviews in chronologic order:
 +Phys Med Biol. 2013 Nov 21;58(22):R221-69.
 +**Chemical exchange saturation transfer (CEST) and MR Z-spectroscopy in vivo: a
 +review of theoretical approaches and methods.**
 +Zaiss M, Bachert P.
 +Chemical exchange saturation transfer (CEST) of metabolite protons that undergo
 +exchange processes with the abundant water pool enables a specific contrast for
 +magnetic resonance imaging (MRI). The CEST image contrast depends on physical and
 +physiological parameters that characterize the microenvironment such as
 +temperature, pH, and metabolite concentration. However, CEST imaging in vivo is a
 +complex technique because of interferences with direct water saturation
 +(spillover effect), the involvement of other exchanging pools, in particular
 +macromolecular systems (magnetization transfer, MT), and nuclear Overhauser
 +effects (NOEs). Moreover, there is a strong dependence of the diverse effects on
 +the employed parameters of radiofrequency irradiation for selective saturation
 +which makes interpretation of acquired signals difficult. This review considers
 +analytical solutions of the Bloch–McConnell (BM) equation system which enable
 +deep insight and theoretical description of CEST and the equivalent off-resonant
 +spinlock (SL) experiments. We derive and discuss proposed theoretical treatments
 +in detail to understand the influence of saturation parameters on the acquired
 +Z-spectrum and how the different effects interfere and can be isolated in MR
 +Z-spectroscopy. Finally, we provide an overview of reported CEST effects in vivo
 +and discuss proposed methods and technical approaches applicable to in vivo CEST
 +studies on clinical MRI systems.
 +Curr Radiol Rep. 2013 Jun 1;1(2):102-114.
 +Chemical Exchange Saturation Transfer (CEST) Imaging: Description of Technique
 +and Potential Clinical Applications.
 +Kogan F(1), Hariharan H, Reddy R.
 +Chemical exchange saturation transfer (CEST) is a magnetic resonance imaging
 +(MRI) contrast enhancement technique that enables indirect detection of
 +metabolites with exchangeable protons. Endogenous metabolites with exchangeable
 +protons including many endogenous proteins with amide protons, glycosaminoglycans
 +(GAG), glycogen, myo-inositol (MI), glutamate (Glu), creatine (Cr) and several
 +others have been identified as potential in vivo endogenous CEST agents. These
 +endogenous CEST agents can be exploited as non-invasive and non-ionizing
 +biomarkers of disease diagnosis and treatment monitoring. This review focuses on
 +the recent technical developments in endogenous in vivo CEST MRI from various
 +metabolites as well as their potential clinical applications. The basic
 +underlying principles of CEST, its potential limitations and new techniques to
 +mitigate them are discussed.
 +J Neuroimaging. 2013 Oct;23(4):526-32. doi: 10.1111/j.1552-6569.2012.00751.x.
 +Epub 2013 Feb 12.
 +Application of chemical exchange saturation transfer (CEST) MRI for endogenous
 +contrast at 7 Tesla.
 +Dula AN(1), Smith SA, Gore JC.
 +Chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI)
 +indirectly images exchangeable solute protons resonating at frequencies different
 +than bulk water. These solute protons are selectively saturated using low
 +bandwidth RF irradiation and saturation is transferred to bulk water protons via
 +chemical exchange, resulting in an attenuation of the measured water proton
 +signal. CEST MRI is an advanced MRI technique with wide application potential due
 +to the ability to examine complex molecular contributions. CEST MRI at high field
 +(7 Tesla [7 T]) will improve the overall results due to increase in signal, T1
 +relaxation time, and chemical shift dispersion. Increased field strength
 +translates to enhanced quantification of the metabolite of interest, allowing
 +more fundamental studies on underlying pathophysiology. CEST contrast is affected
 +by several tissue properties, such as the concentrations of exchange partners and
 +their rate of proton exchange, whose effects have been examined and explored in
 +this review. We have highlighted the background of CEST MRI, typical
 +implementation strategy, and complications at 7 T.
 +Copyright © 2013 by the American Society of Neuroimaging.
 +NMR Biomed. 2013 Jul;26(7):810-28. doi: 10.1002/nbm.2899. Epub 2013 Jan 10.
 +Nuts and bolts of chemical exchange saturation transfer MRI.
 +Liu G(1), Song X, Chan KW, McMahon MT.
 +Chemical exchange saturation transfer (CEST) has emerged as a novel MRI contrast
 +mechanism that is well suited for molecular imaging studies. This new mechanism
 +can be used to detect small amounts of contrast agent through the saturation of
 +rapidly exchanging protons on these agents, allowing a wide range of
 +applications. CEST technology has a number of indispensable features, such as the
 +possibility of simultaneous detection of multiple 'colors' of agents and of
 +changes in their environment (e.g. pH, metabolites, etc.) through MR contrast.
 +Currently, a large number of new imaging schemes and techniques are being
 +developed to improve the temporal resolution and specificity and to correct for
 +the influence of B0 and B1 inhomogeneities. In this review, the techniques
 +developed over the last decade are summarized with the different imaging
 +strategies and post-processing methods discussed from a practical point of view,
 +including the description of their relative merits for the detection of CEST
 +agents. The goal of the present work is to provide the reader with a fundamental
 +understanding of the techniques developed, and to provide guidance to help refine
 +future applications of this technology. This review is organized into three main
 +sections ('Basics of CEST contrast', 'Implementation' and 'Post-processing'), and
 +also includes a brief Introduction and Summary. The 'Basics of CEST contrast'
 +section contains a description of the relevant background theory for saturation
 +transfer and frequency-labeled transfer, and a brief discussion of methods to
 +determine exchange rates. The 'Implementation' section contains a description of
 +the practical considerations in conducting CEST MRI studies, including the choice
 +of magnetic field, pulse sequence, saturation pulse, imaging scheme, and
 +strategies to separate magnetization transfer and CEST. The 'Post-processing'
 +section contains a description of the typical image processing employed for B0
 +/B1 correction, Z-spectral interpolation, frequency-selective detection and
 +improvement of CEST contrast maps.
 +Copyright © 2013 John Wiley & Sons, Ltd.
 + J Magn Reson. 2013 Apr;229:155-72. doi: 10.1016/j.jmr.2012.11.024. Epub 2012 Dec
 +CEST: from basic principles to applications, challenges and opportunities.
 +Vinogradov E(1), Sherry AD, Lenkinski RE.
 +Chemical Exchange Saturation Transfer (CEST) offers a new type of contrast for
 +MRI that is molecule specific. In this approach, a slowly exchanging NMR active
 +nucleus, typically a proton, possessing a chemical shift distinct from water is
 +selectively saturated and the saturated spin is transferred to the bulk water via
 +chemical exchange. Many molecules can act as CEST agents, both naturally
 +occurring endogenous molecules and new types of exogenous agents. A large variety
 +of molecules have been demonstrated as potential agents, including small
 +diamagnetic molecules, complexes of paramagnetic ions, endogenous macromolecules,
 +dendrimers and liposomes. In this review we described the basic principles of the
 +CEST experiment, with emphasis on the similarity to earlier saturation transfer
 +experiments described in the literature. Interest in quantitative CEST has also
 +resulted in the development of new exchange-sensitive detection schemes. Some
 +emerging clinical applications of CEST are described and the challenges and
 +opportunities associated with translation of these methods to the clinical
 +environment are discussed.
 +Copyright © 2012 Elsevier Inc. All rights reserved.
 +Magn Reson Med. 2011 Apr;65(4):927-48. doi: 10.1002/mrm.22761. Epub 2011 Feb 17.
 +Chemical exchange saturation transfer (CEST): what is in a name and what isn't?
 +van Zijl PC, Yadav NN.
 +Chemical exchange saturation transfer (CEST) imaging is a relatively new magnetic
 +resonance imaging contrast approach in which exogenous or endogenous compounds
 +containing either exchangeable protons or exchangeable molecules are selectively
 +saturated and after transfer of this saturation, detected indirectly through the
 +water signal with enhanced sensitivity. The focus of this review is on basic
 +magnetic resonance principles underlying CEST and similarities to and differences
 +with conventional magnetization transfer contrast. In CEST magnetic resonance
 +imaging, transfer of magnetization is studied in mobile compounds instead of
 +semisolids. Similar to magnetization transfer contrast, CEST has contributions of
 +both chemical exchange and dipolar cross-relaxation, but the latter can often be
 +neglected if exchange is fast. Contrary to magnetization transfer contrast, CEST
 +imaging requires sufficiently slow exchange on the magnetic resonance time scale
 +to allow selective irradiation of the protons of interest. As a consequence,
 +magnetic labeling is not limited to radio-frequency saturation but can be
 +expanded with slower frequency-selective approaches such as inversion, gradient
 +dephasing and frequency labeling. The basic theory, design criteria, and
 +experimental issues for exchange transfer imaging are discussed. A new
 +classification for CEST agents based on exchange type is proposed. The potential
 +of this young field is discussed, especially with respect to in vivo application
 +and translation to humans.
 +Copyright © 2011 Wiley-Liss, Inc.
 +Contrast Media Mol Imaging. 2010 Mar-Apr;5(2):78-98. doi: 10.1002/cmmi.369.
 +Encoding the frequency dependence in MRI contrast media: the emerging class of
 +CEST agents.
 +Terreno E(1), Castelli DD, Aime S.
 +CEST agents represent a very promising class of MRI contrast media as they encode
 +a frequency dependence that is not like the classical relaxation-based agents.
 +This peculiar property enables novel applications such as the detection of more
 +than one agent in the same MR image as well as the set-up of ratiometric methods
 +for the quantitative assessment of physico-chemical and biological parameters
 +that characterize the micro-environment in which they are distributed. This
 +survey is aimed at providing the reader with the basic properties and the
 +potential of these compounds. Fundamental aspects, such as the theoretical basis
 +of the saturation transfer via chemical exchange, the generation of the CEST
 +contrast, the classification and sensitivity of CEST agents, and some
 +representative examples displaying their potential in the field of MR-molecular
 +imaging, are presented and discussed in detail.
 +2010 John Wiley & Sons, Ltd.
 +Annu Rev Biomed Eng. 2008;10:391-411. doi:
 +Chemical exchange saturation transfer contrast agents for magnetic resonance
 +Sherry AD(1), Woods M.
 +Magnetic resonance imaging (MRI) contrast agents have become an important tool in
 +clinical medicine. The most common agents are Gd(3+)-based complexes that shorten
 +bulk water T(1) by rapid exchange of a single inner-sphere water molecule with
 +bulk solvent water. Current gadolinium agents lack tissue specificity and
 +typically do not respond to their chemical environment. Recently, it has been
 +demonstrated that MR contrast may be altered by an entirely different mechanism
 +based on chemical exchange saturation transfer (CEST). CEST contrast can
 +originate from exchange of endogenous amide or hydroxyl protons or from
 +exchangeable sites on exogenous CEST agents. This has opened the door for the
 +discovery of new classes of responsive agents ranging from MR gene reporter
 +molecules to small molecules that sense their tissue environment and respond to
 +biological events.
 +Progress in Nuclear Magnetic Resonance Spectroscopy, Volume 48, Issues 2–3, 30 May 2006, Pages 109-136, ISSN 0079-6565,
 +Chemical exchange saturation transfer imaging and spectroscopy
 +Jinyuan Zhou, Peter C.M. van Zijl,
the_reviews.txt · Last modified: 2020/06/15 11:53 (external edit)