Correlation of spectroscopy and magnetization transfer imaging in the evaluation of demyelinating lesions and normal appearing white matter in multiple sclerosis.

abstract：PURPOSE:Evaluate the usefulness of single-shot and of interleaved spatiotemporally encoded (SPEN) methods to perform diffusion tensor imaging (DTI) under various preclinical and clinical settings. METHODS:A formalism for analyzing SPEN DTI data is presented, tailored to account for the spatially dependent b-matrix wei...

journal_title：Magnetic resonance in medicine

authors： Solomon E,Liberman G,Nissan N,Frydman L

更新日期：2017-03-01 00:00:00

abstract：:Traditionally, the method of nonlinear least squares (NLLS) analysis has been used to estimate the parameters obtained from exponential decay data. In this study, we evaluated the use of Bayesian probability theory to analyze such data; specifically, that resulting from intravoxel incoherent motion NMR experiments. An...

journal_title：Magnetic resonance in medicine

authors： Neil JJ,Bretthorst GL

更新日期：1993-05-01 00:00:00

abstract：PURPOSE:A multi-turn transmit surface coil design was presented to improve B1 efficiency when used with current source amplification. METHODS:Three different coil designs driven by an on-coil current-mode class-D amplifier with current envelope feedback were tested on the benchtop and through imaging in a 1.5 T scanne...

journal_title：Magnetic resonance in medicine

authors： Gudino N,Griswold MA

更新日期：2013-04-01 00:00:00

abstract：:Four-dimensional (4D) flow imaging has been used to study flow patterns and pathophysiology, usually focused on specific thoracic vessels and cardiac chambers. Whole-heart 4D flow at high measurement accuracy covering the entire thoracic cardiovascular system would be desirable to simplify and improve hemodynamic asse...

journal_title：Magnetic resonance in medicine

authors： Uribe S,Beerbaum P,Sørensen TS,Rasmusson A,Razavi R,Schaeffter T

更新日期：2009-10-01 00:00:00

abstract：:Artery wall motion and strain play important roles in vascular remodeling and may be important in the pathogenesis of vascular disease. In vivo observations of circumferentially nonuniform wall motion in the human aorta suggest that nonuniform strain may contribute to the localization of vascular pathology. A velocity...

journal_title：Magnetic resonance in medicine

authors： Draney MT,Arko FR,Alley MT,Markl M,Herfkens RJ,Pelc NJ,Zarins CK,Taylor CA

更新日期：2004-08-01 00:00:00

abstract：:Accurate and reproducible MRI R2 * relaxometry for tissue iron quantification is important in managing transfusion-dependent patients. MRI data are often acquired using array coils and reconstructed by the root-sum-square algorithm, and as such, measured signals follow the noncentral chi distribution. In this study, t...

journal_title：Magnetic resonance in medicine

authors： Feng Y,He T,Gatehouse PD,Li X,Harith Alam M,Pennell DJ,Chen W,Firmin DN

更新日期：2013-12-01 00:00:00

abstract：PURPOSE:Quantitative mapping of the native T1 of the heart using the modified look-locker inversion recovery (MOLLI) technique provides high quality diagnostic information without requiring contrast agents. Previous work has considered the effects of T2 relaxation on MOLLI T1 measurements, finding that the T1 measured ...

journal_title：Magnetic resonance in medicine

authors： Robson MD,Piechnik SK,Tunnicliffe EM,Neubauer S

更新日期：2013-09-01 00:00:00

abstract：:The success in utilizing in vivo NMR to identify and/or monitor metabolic abnormalities will be determined in large part on the reliability with which the spectral parameters of the metabolites present can be measured. For these reasons it is clear that there is a need for the development of algorithms with which to o...

journal_title：Magnetic resonance in medicine

authors： Lenkinski RE,Allman T,Scheiner JD,Deming SN

更新日期：1989-06-01 00:00:00

abstract：:A modified Prony method (MPM) was applied to analyze the main signals present in spatially resolved 31P NMR spectra of MCF7 breast tumors implanted in nude mice. First, the method was tested on synthetic data to establish its limits of reliability. Its performance with respect to peak identification and quantification...

journal_title：Magnetic resonance in medicine

authors： Viti V,Ragona R,Guidoni L,Barone P,Furman E,Degani H

更新日期：1997-08-01 00:00:00

abstract：:Multislice, two-dimensional phosphorus 31 spectroscopic imaging (SI) of human brain was performed in 15 normal volunteers on a 3-Tesla magnetic resonance system. Images of free magnesium concentrations and pH as well as phosphoesters, inorganic phosphate, phosphocreatine, and adenosine triphosphate (ATP), were calcula...

journal_title：Magnetic resonance in medicine

authors： Barker PB,Butterworth EJ,Boska MD,Nelson J,Welch KM

更新日期：1999-02-01 00:00:00

abstract：:Respiratory motion and pulsatile blood flow can generate artifacts in morphological and functional lung imaging. Total acquisition time, and thus the achievable signal to noise ratio, is limited when performing breath-hold and/or electrocardiogram-triggered imaging. To overcome these limitations, imaging during free r...

journal_title：Magnetic resonance in medicine

authors： Oechsner M,Pracht ED,Staeb D,Arnold JF,Köstler H,Hahn D,Beer M,Jakob PM

更新日期：2009-03-01 00:00:00

abstract：PURPOSE:To develop and validate a data processing technique that allows phase-contrast MRI-based 4D flow imaging of the aortic valve in a single breath-hold. THEORY AND METHODS:To regularize the ill-posed inverse problem, we extend a recently proposed 2D phase-contrast MRI method to 4D flow imaging. Adopting an empiri...

journal_title：Magnetic resonance in medicine

authors： Rich A,Potter LC,Jin N,Liu Y,Simonetti OP,Ahmad R

更新日期：2019-02-01 00:00:00

abstract：:The incoherent displacement of water in living tissues is of considerable interest because of the widespread use of diffusion-weighted MRI, for which image contrast is based on the water apparent diffusion coefficient (ADC). It has been hypothesized that the decrease in water ADC associated with brain injury is primar...

journal_title：Magnetic resonance in medicine

authors： Sehy JV,Ackerman JJ,Neil JJ

更新日期：2002-07-01 00:00:00

abstract：:The authors present their 1-year experience with the use of 3DFT, time-of-flight MR angiography for the evaluation of vascular diseases of the head and neck. Their experience with over 150 patients indicates that this examination may be performed in conjunction with standard spin-echo imaging with only a minimal incre...

journal_title：Magnetic resonance in medicine

authors： Masaryk TJ,Laub GA,Modic MT,Ross JS,Haacke EM

更新日期：1990-05-01 00:00:00

abstract：:Lactate is a key metabolite and its rates of cellular uptake and release, its production rates from glucose and glycogen, and its interconversion rate with pyruvate are important determinants of cellular energy production. If lactate precursors such as pyruvate and glucose are labeled appropriately with (13)C, (1)H NM...

journal_title：Magnetic resonance in medicine

authors： Lloyd SG,Zeng H,Wang P,Chatham JC

更新日期：2004-06-01 00:00:00

abstract：:Ferumoxytol is an ultrasmall superparamagnetic iron oxide agent marketed for the treatment of anemia. There has been increasing interest in its properties as an MRI contrast agent as well as greater awareness of its adverse event profile. This mini-review summarizes the current state of knowledge of the risks of ferum...

journal_title：Magnetic resonance in medicine

authors： Vasanawala SS,Nguyen KL,Hope MD,Bridges MD,Hope TA,Reeder SB,Bashir MR

更新日期：2016-05-01 00:00:00

abstract：PURPOSE:To develop a fast and accurate method for 3D T2 mapping of prostate cancer using undersampled acquisition and dictionary-based fitting. METHODS:3D high-resolution T2 -weighted images (0.9 × 0.9 × 3 mm3 ) were obtained with a multishot T2 -prepared balanced steady-state free precession (T2 -prep-bSSFP) acquisit...

journal_title：Magnetic resonance in medicine

authors： Roccia E,Vidya Shankar R,Neji R,Cruz G,Munoz C,Botnar R,Goh V,Prieto C,Dregely I

更新日期：2019-03-01 00:00:00

abstract：PURPOSE:To study the utility of fractional calculus in modeling gradient-recalled echo MRI signal decay in the normal human brain. METHODS:We solved analytically the extended time-fractional Bloch equations resulting in five model parameters, namely, the amplitude, relaxation rate, order of the time-fractional derivat...

journal_title：Magnetic resonance in medicine

authors： Qin S,Liu F,Turner IW,Yu Q,Yang Q,Vegh V

更新日期：2017-04-01 00:00:00

abstract：PURPOSE:The purpose of this work was to develop and evaluate a robust water-fat separation method for T1-weighted symmetric two-point Dixon data. THEORY AND METHODS:A method for water-fat separation by phase unwrapping of the opposite-phase images by phase-sensitive reconstruction (PSR) is introduced. PSR consists of ...

journal_title：Magnetic resonance in medicine

authors： Romu T,Dahlström N,Leinhard OD,Borga M

更新日期：2017-09-01 00:00:00

abstract：:In the ongoing quest for faster imaging and higher spatial resolution, several methods have been developed to speed up data acquisition by incorporating prior information about the object being imaged. This study shows that many of these methods can be integrated into a single common equation. The unified framework pr...

journal_title：Magnetic resonance in medicine

authors： Tsao J,Behnia B,Webb AG

更新日期：2001-10-01 00:00:00

abstract：PURPOSE:To develop the simultaneous acquisition of multiple voxels in localized MR spectroscopy (MRS) using sensitivity encoding, allowing reduced total scan time compared to conventional sequential single voxel (SV) acquisition methods. METHODS:Dual volume localization was used to simultaneously excite voxels in both...

journal_title：Magnetic resonance in medicine

authors： Boer VO,Klomp DW,Laterra J,Barker PB

更新日期：2015-09-01 00:00:00

abstract：PURPOSE:Banding artifacts in images acquired by balanced steady-state free precession (bSSFP) remain a challenge in MRI as they considerably reduce image quality, and diagnostic value deteriorates accordingly. As the steady-state tolerates small shifts in frequency, it is possible to acquire frequency-modulated bSSFP. ...

journal_title：Magnetic resonance in medicine

authors： Slawig A,Wech T,Ratz V,Tran-Gia J,Neubauer H,Bley T,Köstler H

更新日期：2017-12-01 00:00:00

abstract：:AFI (actual flip angle imaging) represents an interesting approach to map the B(1) transmit fields by measuring the spatial variations of the effective flip angle. However, the accuracy of the technique relies on the adequate spoiling of transverse magnetization. In the present work configuration theory was employed t...

journal_title：Magnetic resonance in medicine

authors： Nehrke K

更新日期：2009-01-01 00:00:00

abstract：:Aim of the study was to determine distribution and depletion patterns of intramyocellular lipids (IMCL) in leg muscles before and after two types of standardized endurance exercise. ¹H-magnetic resonance spectroscopic imaging was performed (1) in the thigh of eight-trained cyclists after exercising on an ergometer for...

journal_title：Magnetic resonance in medicine

authors： Vermathen P,Saillen P,Boss A,Zehnder M,Boesch C

更新日期：2012-11-01 00:00:00

abstract：:An eight-channel receive-only brain coil and table-top detunable volume transmit coil were developed and tested at 7 T for human imaging. Optimization of this device required attention to sources of interaction between the array elements, between the transmit and receive coils and minimization of common mode currents ...

journal_title：Magnetic resonance in medicine

authors： Wiggins GC,Potthast A,Triantafyllou C,Wiggins CJ,Wald LL

更新日期：2005-07-01 00:00:00

abstract：PURPOSE:Multi-echo spin-echo (MSE) transverse relaxometry mapping using multi-component models is used to study disease activity in neuromuscular disease by assessing the T2 of the myocytic component (T2water ). Current extended phase graph algorithms are not optimized for fat fractions above 50% and the effects of ina...

journal_title：Magnetic resonance in medicine

authors： Keene KR,Beenakker JM,Hooijmans MT,Naarding KJ,Niks EH,Otto LAM,van der Pol WL,Tannemaat MR,Kan HE,Froeling M

更新日期：2020-11-01 00:00:00

abstract：PURPOSE:To assess volumetric proton MR spectroscopic imaging (MRSI) of the human brain on multivendor MRI instruments. METHODS:Echo-planar spectroscopic imaging was developed on instruments from three manufacturers, with matched specifications and acquisition protocols that accounted for differences in sampling perfor...

journal_title：Magnetic resonance in medicine

authors： Sabati M,Sheriff S,Gu M,Wei J,Zhu H,Barker PB,Spielman DM,Alger JR,Maudsley AA

更新日期：2015-11-01 00:00:00

abstract：:Experimental procedures for obtaining localized 31P NMR spectra of humans by means of the ISIS sequence are discussed in detail. The technique is optimized for use with volume coils and with surface coils in order to measure localized 31P NMR spectra of different tissues and organs. Selective frequency-modulated (FM) ...

journal_title：Magnetic resonance in medicine

authors： Luyten PR,Groen JP,Vermeulen JW,den Hollander JA

更新日期：1989-07-01 00:00:00

abstract：:Radiofrequency (RF) -spoiled gradient echo sequences were developed with the aim to produce images with T(1) weighted contrast within short acquisition time. Over the past two decades, this type of sequence has proven to be a robust technique and represents a reliable workhorse in clinical MRI. This study presents an ...

journal_title：Magnetic resonance in medicine

authors： Leupold J,Hennig J,Scheffler K

更新日期：2008-07-01 00:00:00

abstract：:A method is suggested whereby the shifted extracellular triple quantum filtered 23Na signal of an isolated organ is completely eliminated. The method is based on the long relaxation time of the triple quantum coherence and on its fast evolution rate. When the carrier frequency is set on top of the intracellular sodium...

journal_title：Magnetic resonance in medicine

authors： Navon G

更新日期：1993-10-01 00:00:00