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2011, Journal of Magnetic Resonance
NMR in biomedicine
Quantitative rotating frame relaxometry methods in MRI2016 •
Macromolecular degeneration and biochemical changes in tissue can be quantified using rotating frame relaxometry in MRI. It has been shown in several studies that the rotating frame longitudinal relaxation rate constant (R1ρ ) and the rotating frame transverse relaxation rate constant (R2ρ ) are sensitive biomarkers of phenomena at the cellular level. In this comprehensive review, existing MRI methods for probing the biophysical mechanisms that affect the rotating frame relaxation rates of the tissue (i.e. R1ρ and R2ρ ) are presented. Long acquisition times and high radiofrequency (RF) energy deposition into tissue during the process of spin-locking in rotating frame relaxometry are the major barriers to the establishment of these relaxation contrasts at high magnetic fields. Therefore, clinical applications of R1ρ and R2ρ MRI using on- or off-resonance RF excitation methods remain challenging. Accordingly, this review describes the theoretical and experimental approaches to the des...
NMR in biomedicine
The follow-up of progressive hypertrophic cardiomyopathy using magnetic resonance rotating frame relaxation times2017 •
Magnetic resonance rotating frame relaxation times are an alternative non-contrast agent choice for the diagnosis of chronic myocardial infarct. Fibrosis typically occurs in progressive hypertrophic cardiomyopathy. Fibrosis has been imaged in myocardial infarcted tissue using rotating frame relaxation times, which provides the possibility to follow up progressive cardiomyopathy without contrast agents. Mild and severe left ventricular hypertrophy were induced in mice by transverse aortic constriction, and the longitudinal rotating frame relaxation times (T1ρ ) and relaxation along the fictitious field (TRAFF2 , TRAFF3 ) were measured at 5, 10, 24, 62 and 89 days after transverse aortic constriction in vivo. Myocardial fibrosis was verified using Masson's trichrome staining. Increases in the relative relaxation time differences of T1ρ , together with TRAFF2 and TRAFF3 , between fibrotic and remote tissues over time were observed. Furthermore, TRAFF2 and TRAFF3 showed higher relax...
In the present study we derive a solution for two site fast exchange-induced relaxation in the presence of a fictitious magnetic field as generated by amplitude and frequency modulated RF pulses. This solution provides a means to analyze data obtained from relaxation experiments with the method called RAFFn (Relaxation Along a Fictitious Field of rank n), in which a fictitious field is created in a coordinate frame undergoing multi-fold rotation about n axes (rank n). The RAFF2 technique is relevant to MRI relaxation methods that provide good contrast enhancement for tumor detection. The relaxation equations for n = 2 are derived for the fast exchange regime using density matrix formalism. The method of derivation can be further extended to obtain solutions for n > 2. Published by Elsevier Inc.
Journal of Magnetic Resonance Imaging
Combined off-resonance imaging and T2 relaxation in the rotating frame for positive contrast MR imaging of infection in a murine burn model2010 •
In the present study we derive expressions for relaxation rate functions due to dipolar interactions between identical spins in the rotating frames of rank greater than or equal to 3. The rotating frames are produced due to fictitious magnetic field as generated by amplitude and frequency modulated radiofrequency (RF) pulses operating in non-adiabatic regime. This solution provides a means for description of the relaxations during method entitled Relaxation Along a Fictitious Field (RAFF) in the rotating frame of rank n (RAFFn), in which a fictitious field is created in a coordinate frame undergoing multi-fold rotation about n axes (i.e., rank n). We validate the proposed model by comparison with the accepted trigonometric relations for relaxation rates between tilted frames. The agreement between the proposed model for RAFF3 and the trigonometric model is excellent.
2015 •
Journal of Magnetic Resonance
Heteronuclear Adiabatic Relaxation Dispersion (HARD) for quantitative analysis of conformational dynamics in proteins2012 •
Journal of Orthopaedic Research
Evaluation of articular cartilage with quantitative MRI in an equine model of post‐traumatic osteoarthritisMagnetic Resonance in Medicine
Low-power adiabatic sequences for in vivo localized two-dimensional chemical shift correlated MR spectroscopy2010 •
Parkinsonism & Related Disorders
Magnetization transfer and adiabatic R1ρ MRI in the brainstem of Parkinson’s disease2012 •
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Global Journal of Medical Research
Effect of RF Fields During Pulse on Rotational Diffusion: Influence on Spectral DensityJournal of Magnetic Resonance
Nonlinear magnetic field gradients can reduce SAR in flow-driven arterial spin labeling measurements2007 •
Journal of Biomolecular NMR
Joint composite-rotation adiabatic-sweep isotope filtration2007 •
Journal of Cardiovascular Magnetic Resonance
Endogenous assessment of chronic myocardial infarction with T1ρ-mapping in patients2014 •
Journal of the American Chemical Society
Probing Slow Protein Dynamics by Adiabatic R 1ρ and R 2ρ NMR Experiments2010 •
Measurement Science and Technology
A comparison of magnetic resonance methods for spatially resolved T 2 distribution measurements in porous media2015 •
Magnetic Resonance in Medicine
Spin-locking versus chemical exchange saturation transfer MRI for investigating chemical exchange process between water and labile metabolite protons2011 •
Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine
Rotating frame spin lattice relaxation in a swine model of chronic, left ventricular myocardial infarction2010 •
IEEE Transactions on Medical Imaging
Generating Super Stimulated-Echoes in MRI and Their Application to Hyperpolarized C-13 Diffusion Metabolic Imaging2000 •
Magnetic Resonance in Medicine
Erratum to Spin-locking versus chemical exchange saturation transfer MRI for investigating chemical exchange process between water and labile metabolite protons. Magn Reson Med 2011;65:1448-14602012 •
Journal of Magnetic Resonance
Gapped pulses for frequency-swept MRIMagnetic Resonance in Medicine
Validation and optimization of adiabatic T1ρand T2ρfor quantitative imaging of articular cartilage at 3 T2016 •
Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine
Selective magnetic resonance imaging of magnetic nanoparticles by acoustically induced rotary saturation2014 •
2008 •
Magnetic Resonance in Medicine
Quantitative cardiac 31 P spectroscopy at 3 Tesla using adiabatic pulses2009 •
Journal of Magnetic Resonance
Theoretical studies of the effect of the dipolar field in multiple spin-echo sequences with refocusing pulses of finite duration2007 •
Journal of magnetic resonance (San Diego, Calif. : 1997)
Balanced Steady-State Free Precession (bSSFP) from an effective field perspective: Application to the detection of chemical exchange (bSSFPX)2016 •
Journal of Magnetic Resonance
Chemical shift anisotropy selective inversion2009 •
NMR in Biomedicine
Magnetization transfer effects on the efficiency of flow-driven adiabatic fast passage inversion of arterial blood2007 •
Journal of Magnetic Resonance
Dipolar recoupling in solid state NMR by phase alternating pulse sequences2009 •
Magnetic Resonance in Medicine
Rapid B1+ mapping using a preconditioning RF pulse with TurboFLASH readout2000 •
Journal of Magnetic Resonance
pCEST: Positive contrast using Chemical Exchange Saturation Transfer2012 •
Journal of Magnetic Resonance
Spectroscopic imaging with improved gradient modulated constant adiabaticity pulses on high-field clinical scanners2010 •
Journal of Magnetic Resonance Imaging
A pulse sequence for rapid in vivo spin-locked MRI2006 •
Journal of Cerebral Blood Flow & Metabolism
Quantitative assessment of water pools by T1ρ and T2ρ MRI in acute cerebral ischemia of the rat2009 •
Magnetic Resonance in Medicine
Spatial distribution and relationship of T 1ρ and T 2 relaxation times in knee cartilage with osteoarthritis2009 •
The Journal of Chemical Physics
Dynamic nuclear polarization at high magnetic fields2008 •
Journal of the American Chemical Society
Proton-Evolved Local-Field Solid-State NMR Studies of Cytochrome b 5 Embedded in Bicelles, Revealing both Structural and Dynamical Information2010 •
Magnetic Resonance in Medicine
T1ρ contrast in functional magnetic resonance imaging2005 •
Magnetic Resonance in Medicine
On- and off-resonanceT1? MRI in acute cerebral ischemia of the rat2003 •
Magnetic Resonance in Medicine
A new method for detecting exchanging amide protons using chemical exchange rotation transfer2013 •
Journal of Magnetic Resonance
Pre-SAT180, a simple and effective method for residual water suppression2008 •
2008 •
Magnetic Resonance in Medicine
Pseudo-continuous transfer insensitive labeling technique2011 •
Magnetic Resonance in Medicine
In vivoT1ρ mapping in cartilage using 3D magnetization-prepared angle-modulated partitionedk-space spoiled gradient echo snapshots (3D MAPSS)2008 •
Journal of Magnetic Resonance
Sodium inversion recovery MRI of the knee joint in vivo at 7T