Transceive surface coil array for magnetic resonance imaging of the human brain at 4 T.

abstract：:The image intensity in magnetic resonance magnitude images in the presence of noise is shown to be governed by a Rician distribution. Low signal intensities (SNR < 2) are therefore biased due to the noise. It is shown how the underlying noise can be estimated from the images and a simple correction scheme is provided ...

journal_title：Magnetic resonance in medicine

authors： Gudbjartsson H,Patz S

更新日期：1995-12-01 00:00:00

abstract：:High-signal artifacts produced by cerebrospinal fluid (CSF) flow can adversely affect fluid-attenuated inversion recovery (FLAIR) imaging of the brain and spinal cord. This study explores the use of a nonslice-selective inversion pulse to eliminate CSF flow artifacts together with a technique called "K-space Reordered...

journal_title：Magnetic resonance in medicine

authors： Herlihy AH,Oatridge A,Curati WL,Puri BK,Bydder GM,Hajnal JV

更新日期：2001-08-01 00:00:00

abstract：:Magnetization transfer imaging (MT) and localized proton spectroscopy (1H-MRS) were utilized in the evaluation of lesions (high signal abnormalities on T2-weighted images) and normal-appearing white matter (NAWM) in multiple sclerosis (MS). Eleven patients with a clinical diagnosis of MS were independently evaluated w...

journal_title：Magnetic resonance in medicine

authors： Hiehle JF Jr,Lenkinski RE,Grossman RI,Dousset V,Ramer KN,Schnall MD,Cohen JA,Gonzalez-Scarano F

更新日期：1994-09-01 00:00:00

abstract：:Signal-to-noise ratio (SNR) is a major challenge to sodium magnetic resonance imaging. Phased array coils have been shown significantly improving SNR in proton imaging over volume coils. This study investigates SNR advantage of a 15-channel array head coil (birdcage volume coil for transmit/receive and 15-channel arra...

journal_title：Magnetic resonance in medicine

authors： Qian Y,Zhao T,Wiggins GC,Wald LL,Zheng H,Weimer J,Boada FE

更新日期：2012-12-01 00:00:00

abstract：PURPOSE:The purpose of this study was to investigate the feasibility of in vivo imaging of human pancreatic ductal cells by OATP1B3 reporter gene under MRI. METHODS:A human cell line (PANC-1) derived from the pancreatic ductal epithelium was used in this study. After transduction of OATP1B3, the cellular physiological...

journal_title：Magnetic resonance in medicine

authors： Wu MR,Hsiao JK,Liu HM,Huang YY,Tseng YJ,Chou PT,Weng TI,Yang CY

更新日期：2019-08-01 00:00:00

abstract：:We improved the three-point phase-contrast method by regularization of MR velocity data after acquisition of a low velocity-to-noise ratio (VNR) velocity image and a high VNR aliased velocity image. The phase unwrapping algorithm is based on the assumed correlation of the velocity of adjacent flow voxels on the low VN...

journal_title：Magnetic resonance in medicine

authors： Herment A,Mousseaux E,Jolivet O,DeCesare A,Frouin F,Todd-Pokropek A,Bittoun J

更新日期：2000-07-01 00:00:00

abstract：:The proton T(1) was measured at 132 μT in ex vivo prostate tissue specimens from radical prostatectomies of 35 patients with prostate cancer. Each patient provided two specimens. The NMR and MRI measurements involved proton repolarization, a field of typically 150 mT and detection of the 5.6-kHz signal with a supercon...

journal_title：Magnetic resonance in medicine

authors： Busch S,Hatridge M,Mößle M,Myers W,Wong T,Mück M,Chew K,Kuchinsky K,Simko J,Clarke J

更新日期：2012-04-01 00:00:00

abstract：PURPOSE:To achieve highly accelerated submillimeter resolution T 2 -weighted functional MRI at 7T by developing a three-dimensional gradient and spin echo imaging (GRASE) with inner-volume sel...

journal_title：Magnetic resonance in medicine

authors： Park S,Torrisi S,Townsend JD,Beckett A,Feinberg DA

更新日期：2020-11-24 00:00:00

abstract：PURPOSE:The purpose of this study is to increase the robustness of MR fingerprinting (MRF) toward subject motion. METHODS:A novel reconstruction algorithm, MOtion insensitive MRF (MORF), was developed, which uses an iterative reconstruction based retrospective motion correction approach. Each iteration loops through t...

journal_title：Magnetic resonance in medicine

authors： Mehta BB,Ma D,Pierre EY,Jiang Y,Coppo S,Griswold MA

更新日期：2018-12-01 00:00:00

abstract：:Cerebral blood volume changes with arterial carbon dioxide were monitored by proton T1-weighted MR images following administration of the intravascular contrast agent Gd-DTPA labeled with human serum albumin. Without MR contrast, no significant image intensity changes were observed with PaCO2. Following contrast, regi...

journal_title：Magnetic resonance in medicine

authors： Moseley ME,Chew WM,White DL,Kucharczyk J,Litt L,Derugin N,Dupon J,Brasch RC,Norman D

更新日期：1992-01-01 00:00:00

abstract：:Gradient-echo EPI, blood oxygenation level-dependent (BOLD) functional MRI (fMRI) using parallel imaging (PI) is demonstrated at 7 Tesla with 16 channels, a fourfold 1D reduction factor (R), and fourfold maximal aliasing. The resultant activation detection in finger-tapping fMRI studies was robust, in full agreement w...

journal_title：Magnetic resonance in medicine

authors： Moeller S,Van de Moortele PF,Goerke U,Adriany G,Ugurbil K

更新日期：2006-07-01 00:00:00

abstract：PURPOSE:A purely experimental method for MRI-based transfer function (TF) determination is presented. A TF characterizes the potential for radiofrequency heating of a linear implant by relating the incident tangential electric field to a scattered electric field at its tip. We utilize the previously introduced transfer...

journal_title：Magnetic resonance in medicine

authors： Tokaya JP,Raaijmakers AJE,Luijten PR,Sbrizzi A,van den Berg CAT

更新日期：2020-03-01 00:00:00

abstract：PURPOSE:To demonstrate how triple diffusion encoding (TDE) MRI can be applied to separately estimate the intra-axonal and extra-axonal diffusion tensors in white matter (WM). METHODS:Using a TDE pulse sequence with an axially symmetric b-matrix, diffusion MRI data were acquired at 3T for 3 healthy adults with an axial...

journal_title：Magnetic resonance in medicine

authors： Ramanna S,Moss HG,McKinnon ET,Yacoub E,Helpern JA,Jensen JH

更新日期：2020-06-01 00:00:00

abstract：:Techniques are described for the (31)P NMR analysis of glycerophospholipid (PL) headgroup and molecular species in brain. The (31)P NMR spectrum of PLs from human temporal cortex, solubilized in aqueous Na cholate, typically showed 3 major resonances, assigned to phosphatidylcholine (PC) molecular species containing 0...

journal_title：Magnetic resonance in medicine

authors： Pearce JM,Komoroski RA

更新日期：2000-08-01 00:00:00

abstract：:Quantitative 1H MRS to determine cerebral metabolite patterns and MRI to determine CSF flow were applied to 12 patients with ventricular dilation-Group A, cortical atrophy (N = 5); or Group B, hydrocephalus (N = 7)- and in 9 normal controls. While mean brain water (Group A = 80% +/- 6; Group B = 86% +/- 5; normal = 85...

journal_title：Magnetic resonance in medicine

authors： Bluml S,McComb JG,Ross BD

更新日期：1997-03-01 00:00:00

abstract：PURPOSE:Dipole antennas in ultrahigh field MRI have demonstrated advantages over more conventional designs. In this study, the fractionated dipole antenna is presented: a dipole where the legs are split into segments that are interconnected by capacitors or inductors. METHODS:A parameter study has been performed on di...

journal_title：Magnetic resonance in medicine

authors： Raaijmakers AJ,Italiaander M,Voogt IJ,Luijten PR,Hoogduin JM,Klomp DW,van den Berg CA

更新日期：2016-03-01 00:00:00

abstract：PURPOSE:To investigate the uncertainties on relative Cramér-Rao lower bound (rCRB) estimates and demonstrate their biasing effects in MRS quantification. THEORY AND METHODS:Simulations were performed to calculate the distribution of the computed rCRB (noted rCRB*) for several rCRB levels. One hundred thousand simulati...

journal_title：Magnetic resonance in medicine

authors： Bonny JM,Pagès G

更新日期：2019-02-01 00:00:00

abstract：:Two different types of (co-registered) images of the same slice of tissue will generally have different spatial resolutions. The judicious pixel-by-pixel combination of their data can be accomplished to yield a single image exhibiting properties of both. Here, axial (18)FDG PET and (1)H(2)O MR images of the human brai...

journal_title：Magnetic resonance in medicine

authors： Sammi MK,Felder CA,Fowler JS,Lee JH,Levy AV,Li X,Logan J,Pályka I,Rooney WD,Volkow ND,Wang GJ,Springer CS Jr

更新日期：1999-08-01 00:00:00

abstract：:A new parallel imaging technique was implemented which can result in reduced image acquisition times in MRI. MR data is acquired in parallel using an array of receiver coils and then reconstructed simultaneously with multiple processors. The method requires the initial estimation of the 2D sensitivity profile of each ...

journal_title：Magnetic resonance in medicine

authors： Kyriakos WE,Panych LP,Kacher DF,Westin CF,Bao SM,Mulkern RV,Jolesz FA

更新日期：2000-08-01 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 propose a phase error correction scheme for monopolar time-interleaved multi-echo gradient echo water-fat imaging that allows accurate and robust complex-based quantification of the proton density fat fraction (PDFF). METHODS:A three-step phase correction scheme is proposed to address a) a phase term induce...

journal_title：Magnetic resonance in medicine

authors： Ruschke S,Eggers H,Kooijman H,Diefenbach MN,Baum T,Haase A,Rummeny EJ,Hu HH,Karampinos DC

更新日期：2017-09-01 00:00:00

abstract：PURPOSE:A new method, called Transmit and Receive Patterns from Low-Tip-angle gradient-Echo Images (TRIPLET), is described which simultaneously maps the B1+ and B1- fields of a transmit/receive radiofrequency coil array. The input data are low-tip-angle gradient-echo images, which can be acquired in a relatively short ...

journal_title：Magnetic resonance in medicine

authors： Sbrizzi A,Raaijmakers AJ,Hoogduin H,Lagendijk JJ,Luijten PR,van den Berg CA

更新日期：2014-07-01 00:00:00

abstract：:Dynamic MRI tracking of rat T-cells in vivo is performed in rat testicles after labeling isolated rat T-cells in vitro with superparamagnetic dextran-coated iron-oxide particles, BMS180549. Tissue inflammation induced by the local injection of the calcium ionophore, A23187, is used to attract labeled T-cells. Gradient...

journal_title：Magnetic resonance in medicine

authors： Yeh TC,Zhang W,Ildstad ST,Ho C

更新日期：1995-02-01 00:00:00

abstract：:Susceptibility artifacts and transmission radio frequency (RF) field (B(1) +) inhomogeneity are major limitations in high-field gradient echo MRI. Previously proposed numerical 2D spectral-spatial RF pulses have been shown to be promising for reducing the through-plane signal loss susceptibility artifact by incorporat...

journal_title：Magnetic resonance in medicine

authors： Yang C,Deng W,Stenger VA

更新日期：2011-02-01 00:00:00

abstract：PURPOSE:To develop a novel, simultaneous multislice reconstruction method that exploits Hankel subspace learning (SMS-HSL) for aliasing separation in the slice direction. METHODS:An SMS signal model with the Hankel-structured matrix was proposed. To efficiently suppress interslice leakage artifacts from a signal subsp...

journal_title：Magnetic resonance in medicine

authors： Park S,Park J

更新日期：2017-10-01 00:00:00

abstract：:Functional MRI studies to date have been generally performed using the blood oxygenation level dependent (BOLD) contrast mechanism. Recently, it has been proposed that dynamic change in the apparent diffusion coefficient (ADC), measured using intravoxel incoherent motion (IVIM) weighting, can be used as a robust funct...

journal_title：Magnetic resonance in medicine

authors： Harshbarger TB,Song AW

更新日期：2004-12-01 00:00:00

abstract：PURPOSE:To separate the spectrally overlapped lactate and lipid signals at 1.3 ppm using diffusion-weighted magnetic resonance spectroscopy (DW-MRS) based on their large diffusivity difference. METHODS:DW-MRS was applied to the gel phantoms containing lactate and lipid droplets, and to the rat brain tumors. Lactate an...

journal_title：Magnetic resonance in medicine

authors： Wang AM,Leung GK,Kiang KM,Chan D,Cao P,Wu EX

更新日期：2017-02-01 00:00:00

abstract：:The goal of this study was to measure the interindividual reproducibility of glutamate quantification in 1.5-T (1)H MRS of human brains. To determine the effective echo time (TE) for glutamate quantification, spectra from a phantom and 12 participants were obtained with TE = 30, 35, 40, and 144 ms (repetition time (TR...

journal_title：Magnetic resonance in medicine

authors： Jang DP,Lee JM,Lee E,Park S,Kim JJ,Namkoong K,Yoon KJ,Kim IY,Kim SI

更新日期：2005-03-01 00:00:00

abstract：:The focal underdetermined system solver (FOCUSS) was originally designed to obtain sparse solutions by successively solving quadratic optimization problems. This article adapts FOCUSS for a projection reconstruction MR imaging problem to obtain high resolution reconstructions from angular under-sampled radial k-space ...

journal_title：Magnetic resonance in medicine

authors： Ye JC,Tak S,Han Y,Park HW

更新日期：2007-04-01 00:00:00

abstract：PURPOSE:To develop a flexible fast spin echo (FSE) triple-echo Dixon (FTED) technique. METHODS:An FSE pulse sequence was modified by replacing each readout gradient with three fast-switching bipolar readout gradients with minimal interecho dead time. The corresponding three echoes were used to generate three raw image...

journal_title：Magnetic resonance in medicine

authors： Son JB,Hwang KP,Madewell JE,Bayram E,Hazle JD,Low RN,Ma J

更新日期：2017-03-01 00:00:00