Iterative reweighted linear least squares for accurate, fast, and robust estimation of diffusion magnetic resonance parameters.

abstract：:Steady-state free precession (SSFP) methods have been very successful due to their high signal and short imaging times. These properties make them good candidates for applications that intrinsically suffer from low signal such as low gamma nuclei imaging. A new chemical shift imaging (CSI) technique based on the SSFP ...

journal_title：Magnetic resonance in medicine

authors： Speck O,Scheffler K,Hennig J

更新日期：2002-10-01 00:00:00

abstract：:Magnetization transfer effects represent a major source of contrast in multislice turbo spin echo sequences (TSE)/fast spin echo sequences. Generally, low refocusing flip angles have become common in such MRI sequences, especially to mitigate specific absorption rate problems. Since the strength of magnetization trans...

journal_title：Magnetic resonance in medicine

authors： Weigel M,Helms G,Hennig J

更新日期：2010-01-01 00:00:00

abstract：:A novel radio-frequency (RF) pulse design algorithm is presented that generates fast slice-selective excitation pulses that mitigate B+1 inhomogeneity present in the human brain at high field. The method is provided an estimate of the B+1 field in an axial slice of the brain and then optimizes the placement of sinc-li...

journal_title：Magnetic resonance in medicine

authors： Zelinski AC,Wald LL,Setsompop K,Alagappan V,Gagoski BA,Goyal VK,Adalsteinsson E

更新日期：2008-06-01 00:00:00

abstract：:Magnetic resonance imaging allows numerous k-space sampling schemes such as cartesian, polar, spherical, and other non-rectilinear trajectories. Non-rectilinear MR acquisitions permit fast scan times and can suppress motion artifacts. Still, these sampling schemes may adversely affect the image characteristics due to ...

journal_title：Magnetic resonance in medicine

authors： Lauzon ML,Rutt BK

更新日期：1996-12-01 00:00:00

abstract：PURPOSE:Myocardial effective relaxation time T2* is commonly regarded as a surrogate for myocardial tissue oxygenation. However, it is legitimate to assume that there are multiple factors that influence T2*. To this end, this study investigates the relationship between T2* and cardiac macromorphology given by left vent...

journal_title：Magnetic resonance in medicine

authors： Huelnhagen T,Hezel F,Serradas Duarte T,Pohlmann A,Oezerdem C,Flemming B,Seeliger E,Prothmann M,Schulz-Menger J,Niendorf T

更新日期：2017-06-01 00:00:00

abstract：:A multifocal mouse liver tumor model chemically induced with 5,9-dimethyl-7H-dibenzo[c,g]carbazole was investigated by respiratory-triggered morphological and functional MRI (fMRI) at 4.7 Tesla. The model is characterized by the presence of two tumor types: hypovascular cholangioma and vascularized hepatocellular carc...

journal_title：Magnetic resonance in medicine

authors： Thomas CD,Chenu E,Walczak C,Plessis MJ,Perin F,Volk A

更新日期：2003-09-01 00:00:00

abstract：:Parallel transmission has emerged as an efficient means for implementing multidimensional spatially selective radiofrequency excitation pulses. To date, most theoretical and experimental work on parallel transmission radiofrequency (RF) pulse design is based on the small-tip-angle approximation to the Bloch equation. ...

journal_title：Magnetic resonance in medicine

authors： Zheng H,Zhao T,Qian Y,Ibrahim TS,Boada FE

更新日期：2011-09-01 00:00:00

abstract：PURPOSE:Blood flow causes induced voltages via the magnetohydrodynamic (MHD) effect distorting electrograms (EGMs) made during magnetic resonance imaging. To investigate the MHD effect in this context MHD voltages occurring inside the human heart were simulated in an in vitro model system inside a 1.5 T MR system. MET...

journal_title：Magnetic resonance in medicine

authors： Buchenberg WB,Mader W,Hoppe G,Lorenz R,Menza M,Büchert M,Timmer J,Jung B

更新日期：2015-09-01 00:00:00

abstract：:A method is demonstrated for detection of magnetization from a selected region within the sensitive volume of a surface coil in a single acquisition. Composite pulses are described which eliminate signals from regions where magnetization is rotated 270 and 450 degrees. There is a loss of 1.3% or less of signal from re...

journal_title：Magnetic resonance in medicine

authors： Karczmar GS,Matson GB,Weiner MW

更新日期：1986-04-01 00:00:00

abstract：PURPOSE:The purpose of this study was to evaluate a new inline motion compensation approach called image-based navigation with Constant Respiratory efficiency UsIng Single End-expiratory threshold (iNAV-CRUISE) for coronary MR angiography (CMRA). METHODS:The CRUISE gating technique was combined with iNAV motion correc...

journal_title：Magnetic resonance in medicine

authors： Henningsson M,Smink J,van Ensbergen G,Botnar R

更新日期：2018-01-01 00:00:00

abstract：:Algorithms to reliably detect motion in navigator echoes are crucial to many MRI motion suppression techniques. The accuracy of these algorithms is affected by noise and deformation of navigator echo profile caused by physiologic motion. This study compared the performance of algorithms based on correlation and least ...

journal_title：Magnetic resonance in medicine

authors： Wang Y,Grimm RC,Felmlee JP,Riederer SJ,Ehman RL

更新日期：1996-07-01 00:00:00

abstract：PURPOSE:To evaluate the role of true diffusion and flow-related pseudodiffusion in cerebral blood flow (CBF) quantification using arterial spin labeling (ASL) with single-shot or segmented 3D gradient and spin echo (GRASE) readouts. THEORY:The extended phase graph (EPG) algorithm, originally designed to model the effe...

journal_title：Magnetic resonance in medicine

authors： He X,Wengler K,Schweitzer ME

更新日期：2018-08-01 00:00:00

abstract：:In vivo echo-planar MR imaging was used to measure apparent diffusion coefficients (ADC) of cerebral tissues in a comprehensive noninvasive evaluation of early ischemic brain damage induced by occlusion of the middle cerebral artery (MCA) in a cat model of acute regional stroke. Within 10 min after arterial occlusion,...

journal_title：Magnetic resonance in medicine

authors： Kucharczyk J,Mintorovitch J,Asgari HS,Moseley M

更新日期：1991-06-01 00:00:00

abstract：:We describe a doubly tuned radiofrequency (RF) local coil probe designed specifically for performing in vivo image-localized spectroscopy. The probe was designed using principles developed in connection with the counter-rotating-current (CRC) and planar-pair loop gap resonators for magnetic resonance imaging (MRI). Th...

journal_title：Magnetic resonance in medicine

authors： Grist TM,Jesmanowicz A,Kneeland JB,Froncisz W,Hyde JS

更新日期：1988-03-01 00:00:00

abstract：:The objective of this study is to evaluate the effect of MR image resolution on trabecular bone parameters and to determine the acceptable resolution that can be accurately analyzed to assess structural parameters. Ten distal femoral condyle specimens of 1 × 1 × 1 cm(3) were scanned with a 4.7-T Bruker BioSpec MRI sca...

journal_title：Magnetic resonance in medicine

authors： Kim N,Lee JG,Song Y,Kim HJ,S Yeom J,Cho G

更新日期：2012-01-01 00:00:00

abstract：:In the recently proposed technique Sweep Imaging with Fourier Transform (SWIFT), frequency-modulated radiofrequency pulses are used in concert with simultaneous acquisition to facilitate MRI of samples with very short transverse relaxation time. In the present work, sweep MRI is reviewed from a reconstruction perspect...

journal_title：Magnetic resonance in medicine

authors： Weiger M,Hennel F,Pruessmann KP

更新日期：2010-12-01 00:00:00

abstract：:Image reconstruction of tagged cardiac MR images using complementary spatial modulation of magnetization (CSPAMM) requires the subtraction of two complex datasets to remove the untagged signal. Although the resultant images typically have sharper and more persistent tags than images formed without complementary taggin...

journal_title：Magnetic resonance in medicine

authors： NessAiver M,Prince JL

更新日期：2003-08-01 00:00:00

abstract：:A magnetic resonance imaging method is presented for quantifying the degree to which water diffusion in biologic tissues is non-Gaussian. Since tissue structure is responsible for the deviation of water diffusion from the Gaussian behavior typically observed in homogeneous solutions, this method provides a specific me...

journal_title：Magnetic resonance in medicine

authors： Jensen JH,Helpern JA,Ramani A,Lu H,Kaczynski K

更新日期：2005-06-01 00:00:00

abstract：PURPOSE:Measurement of venous oxygenation (Yv) is a critical step toward quantitative assessment of brain oxygen metabolism, a key index in many brain disorders. The present study aims to develop a noninvasive, rapid, and reproducible method to measure Yv in a vessel-specific manner. THEORY:The method, T2-Relaxation-U...

journal_title：Magnetic resonance in medicine

authors： Krishnamurthy LC,Liu P,Ge Y,Lu H

更新日期：2014-03-01 00:00:00

abstract：:Changes in the exchange rate of water across the blood-brain barrier, denoted k(w), may indicate blood-brain barrier dysfunction before the leakage of large-molecule contrast agents is observable. A previously proposed approach for measuring k(w) is to use diffusion-weighted arterial spin labeling to measure the vascu...

journal_title：Magnetic resonance in medicine

authors： St Lawrence KS,Owen D,Wang DJ

更新日期：2012-05-01 00:00:00

abstract：:Noninvasive molecular imaging of angiogenesis could play a critical role in the clinical management of peripheral vascular disease patients. The alpha(nu)beta(3)-integrin, a well-established biomarker of neovascular proliferation, is an ideal target for molecular imaging of angiogenesis. This study investigates whethe...

journal_title：Magnetic resonance in medicine

authors： Winter PM,Caruthers SD,Allen JS,Cai K,Williams TA,Lanza GM,Wickline SA

更新日期：2010-08-01 00:00:00

abstract：:Cervical spinal cord spectroscopy has the potential to add metabolic information to spinal cord MRI and improve the clinical evaluation and research investigation of spinal cord diseases, such as multiple sclerosis (MS) and intraspinal tumors. However, in vivo proton MR spectroscopy ((1)H-MRS) of the spinal cord is di...

journal_title：Magnetic resonance in medicine

authors： Marliani AF,Clementi V,Albini-Riccioli L,Agati R,Leonardi M

更新日期：2007-01-01 00:00:00

abstract：:The use of phase correlation to detect rigid-body translational motion is reviewed and applied to individual echotrains in turbo-spin-echo data acquisition. It is shown that when the same echotrain is acquired twice, the subsampled correlation provides an array of delta-functions, from which the motion that occurred b...

journal_title：Magnetic resonance in medicine

authors： Mendes J,Kholmovski E,Parker DL

更新日期：2009-03-01 00:00:00

abstract：PURPOSE:To characterize pseudo-continuous arterial spin labeling (pCASL) through simulations of spin inversion and to discuss suitable parameter settings for measuring cerebral perfusion. METHODS:Simulations of arterial spin inversion in pCASL were performed based on the Bloch equation. Both the labeling and the contr...

journal_title：Magnetic resonance in medicine

authors： Lorenz K,Mildner T,Schlumm T,Möller HE

更新日期：2018-03-01 00:00:00

abstract：:Continuous arterial spin labeling (CASL) was used to obtain an index of cerebral blood flow (ICBF) in the normal mouse brain and in an orthotopic mouse model of human U87 high-grade glioma at 8.5 T. Under the assumption of a constant tissue:blood partition coefficient for water in different tissues, the mean ICBF (n =...

journal_title：Magnetic resonance in medicine

authors： Sun Y,Schmidt NO,Schmidt K,Doshi S,Rubin JB,Mulkern RV,Carroll R,Ziu M,Erkmen K,Poussaint TY,Black P,Albert M,Burstein D,Kieran MW

更新日期：2004-05-01 00:00:00

abstract：:Experiments have been performed to demonstrate and quantify cross-relaxation between water and methylene resonances in a simple model system. Inversion recovery experiments on aqueous solutions of polyethylene glycol produce a transient nuclear Overhauser effect that alters the recovery of the methylene resonance. The...

journal_title：Magnetic resonance in medicine

authors： Gore JC,Brown MS,Armitage IM

更新日期：1989-03-01 00:00:00

abstract：:The mechanism behind previously observed changes in the apparent diffusion coefficient (ADC) during brain activation is not well understood. Therefore, we investigated the signal source and spatial specificity of functional magnetic resonance imaging (fMRI) ADC changes systematically in the visual cortex of cats using...

journal_title：Magnetic resonance in medicine

authors： Jin T,Zhao F,Kim SG

更新日期：2006-12-01 00:00:00

abstract：:An improved double quantum coherence (DQC) filter for the selective in vivo detection of glutathione (GSH) in the human brain at 1.5 Tesla is presented. The goal was to minimize contamination of the DQC-filtered GSH signal at 2.9 ppm with contributions arising from GABA. The modification consists of tailoring the freq...

journal_title：Magnetic resonance in medicine

authors： Trabesinger AH,Boesiger P

更新日期：2001-04-01 00:00:00

abstract：:High-field (>or=3 T) cardiac MRI is challenged by inhomogeneities of both the static magnetic field (B(0)) and the transmit radiofrequency field (B(1)+). The inhomogeneous B fields not only demand improved shimming methods but also impede the correct determination of the zero-order terms, i.e., the local resonance fre...

journal_title：Magnetic resonance in medicine

authors： Schär M,Vonken EJ,Stuber M

更新日期：2010-02-01 00:00:00

abstract：PURPOSE:A new approach to design parallel transmit (pTx) head arrays is proposed that integrates transmit radiofrequency pulse designs with electromagnetic modeling of array coil elements. THEORY AND METHODS:An approach to design pTx head arrays is proposed that finds optimal groupings of a large number of coils into ...

journal_title：Magnetic resonance in medicine

authors： Cao Z,Yan X,Gore JC,Grissom WA

更新日期：2020-06-01 00:00:00