Piezoelectric-controlled tuning capacitor for surface coils.

abstract：:Dynamic contrast-enhanced (DCE-) MRI is often used to evaluate the response to experimental antiangiogenic therapies in small animal models of cancer. Unfortunately, DCE-MRI studies often require a substantial investment of both time and money to achieve the desired level of statistical significance. Multiple-mouse MR...

journal_title：Magnetic resonance in medicine

authors： Ramirez MS,Ragan DK,Kundra V,Bankson JA

更新日期：2007-09-01 00:00:00

abstract：PURPOSE:Single-scan two-dimensional MRI has been generally constrained to acquisitions in high quality magnets. This study introduces a methodology, cross-term spatiotemporal encoding (xSPEN), that delivers such images under much poorer external field conditions. METHODS:xSPEN departs from conventional k-space scannin...

journal_title：Magnetic resonance in medicine

authors： Zhang Z,Seginer A,Frydman L

更新日期：2017-02-01 00:00:00

abstract：:The multiexponential behavior of the decay curves obtained in vitro by a Carr-Purcell-Meiboom-Gill (CPMG) sequence from spleens and kidneys of mice is analyzed. The mice were inoculated with the acute lymphocytic P388 leukemic cells and treated with the anticancer drug cis-diamminedichloroplatinum(II), cis-Pt. Kidneys...

journal_title：Magnetic resonance in medicine

authors： François A,Van Gerven L,Atassi G,Eisendrath H,Gielen M,Willem R

更新日期：1988-08-01 00:00:00

abstract：PURPOSE:The goal of this study was to conduct an exposure assessment for workers moving through the stray stationary field of common MRI scanners, performed according to the recent International Commission on Non-Ionizing Radiation Protection (ICNIRP) Guidelines, which aim at avoiding annoying sensory effects. THEORY ...

journal_title：Magnetic resonance in medicine

authors： Zilberti L,Bottauscio O,Chiampi M

更新日期：2016-10-01 00:00:00

abstract：:The proton exchange rates between water and the hydroxyl protons of threonine, serine, tyrosine, the amino protons of lysine, and the guanidinium protons of arginine were measured in the pH range 0.5 to 8.5 and for the temperatures 4 degrees C, 10 degrees C, 20 degrees C, 30 degrees C, and 36 degrees C. The intrinsic ...

journal_title：Magnetic resonance in medicine

authors： Liepinsh E,Otting G

更新日期：1996-01-01 00:00:00

abstract：:Three-dimensional magnetization-prepared (MP) MR angiography (MRA) was applied to the carotid and vertebral arteries by using ECG triggering, a slab selective RF inversion pulse, centric phase encoding and acquisition during diastole. Both theoretically and experimentally, the MP MRA sequence was shown to perform well...

journal_title：Magnetic resonance in medicine

authors： Wilman AH,Huston J 3rd,Riederer SJ

更新日期：1997-02-01 00:00:00

abstract：PURPOSE:To enable accurate magnetic resonance (MR) parameter mapping with accelerated data acquisition, utilizing recent advances in constrained imaging with sparse sampling. THEORY AND METHODS:A new constrained reconstruction method based on low-rank and sparsity constraints is proposed to accelerate MR parameter map...

journal_title：Magnetic resonance in medicine

authors： Zhao B,Lu W,Hitchens TK,Lam F,Ho C,Liang ZP

更新日期：2015-08-01 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：:Cortical spreading depression (CSD) was visualized using manganese-enhanced MRI (MEMRI) following topical application of KCl to the exposed rat cortex. MEMRI signal increase in the ipsilateral cortex relative to the contralateral control region was 60 +/- 30% following two KCl applications. MEMRI signal increase for a...

journal_title：Magnetic resonance in medicine

authors： Henning EC,Meng X,Fisher M,Sotak CH

更新日期：2005-04-01 00:00:00

abstract：PURPOSE:T2 -weighted sequences are particularly sensitive to the radiofrequency (RF) field inhomogeneity problem at ultra-high-field because of the errors accumulated by the imperfections of the train of refocusing pulses. As parallel transmission (pTx) has proved particularly useful to counteract RF heterogeneities, u...

journal_title：Magnetic resonance in medicine

authors： Gras V,Mauconduit F,Vignaud A,Amadon A,Le Bihan D,Stöcker T,Boulant N

更新日期：2018-07-01 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:Cross-relaxation of protons with (14) N nuclei in proteins enhances relaxivity in the quadrupolar dip range of typically 2-3 MHz Larmor frequency. The magnitude of these dips was suggested as a means of assessing the degeneracy of articular cartilage during osteoarthritis (OA). However, so far only proteoglycan...

journal_title：Magnetic resonance in medicine

authors： Rössler E,Mattea C,Stapf S

更新日期：2015-05-01 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 develop and evaluate a novel 2D phase-unwrapping method that works robustly in the presence of severe noise, rapid phase changes, and disconnected regions. THEORY AND METHODS:The MR phase map usually varies rapidly in regions adjacent to wraps. In contrast, the phasors can vary slowly, especially in regions...

journal_title：Magnetic resonance in medicine

authors： Cheng J,Mei Y,Liu B,Guan J,Liu X,Wu EX,Feng Q,Chen W,Feng Y

更新日期：2018-01-01 00:00:00

abstract：:Skeletal muscle triglycerides are markers for insulin resistance in type 2 diabetes. Recently, MR spectroscopy was adapted for in vivo measurement of triglycerides in animal models and for the characterization of new therapeutic approaches. Because of small MR spectroscopy voxel sizes used in skeletal muscles, surface...

journal_title：Magnetic resonance in medicine

authors： Neumaier M,Niessen HG,Kaulisch T,Stiller D

更新日期：2009-10-01 00:00:00

abstract：:Emerging applications of sodium bioscales derived from quantitative sodium magnetic resonance imaging assess temporal changes in regional sodium concentration over intervals that vary from hours (monitoring tissue viability in stroke) to weeks (monitoring brain tumor treatment during radiation therapy) or even years (...

journal_title：Magnetic resonance in medicine

authors： Atkinson IC,Lu A,Thulborn KR

更新日期：2012-09-01 00:00:00

abstract：PURPOSE:To test the feasibility of using the SPICE (SPectroscopic Imaging by exploiting spatiospectral CorrElation) technique, which uses the partial separability of spectroscopic data, for high resolution hyperpolarized (HP) 13 C spectroscopic imaging. METHODS:Numerical simulations were performed to investigate the i...

journal_title：Magnetic resonance in medicine

authors： Lee H,Song JE,Shin J,Joe E,Joo CG,Choi YS,Song HT,Kim DH

更新日期：2018-08-01 00:00:00

abstract：:The authors describe a method for accurate in vivo multislice imaging of the active component of the B1 field which is based on a previously proposed method, which uses the signal intensity ratio of two images measured with different excitation angles, and a repetition time TR 5 > or = 5 T1. The new method essentially...

journal_title：Magnetic resonance in medicine

authors： Stollberger R,Wach P

更新日期：1996-02-01 00:00:00

abstract：:In the dynamic nuclear polarization process, microwave irradiation facilitates exchange of polarization from a radical's unpaired electron to nuclear spins at cryogenic temperatures, increasing polarization by >10,000. Doping samples with Gd(3+) ions further increases the achievable solid-state polarization. However, ...

journal_title：Magnetic resonance in medicine

authors： Gordon JW,Fain SB,Rowland IJ

更新日期：2012-12-01 00:00:00

abstract：PURPOSE:The goal of this study is to characterize and improve the accuracy of 2D magnetic resonance fingerprinting (MRF) scans in the presence of slice profile (SP) and B1 imperfections, which are two main factors that affect quantitative results in MRF. METHODS:The SP and B1 imperfections are characterized and correc...

journal_title：Magnetic resonance in medicine

authors： Ma D,Coppo S,Chen Y,McGivney DF,Jiang Y,Pahwa S,Gulani V,Griswold MA

更新日期：2017-11-01 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：:Manganese is a useful contrast agent for MRI of animals. Previously, it has been shown that systemic doses of MnCl(2) provide unique contrast in the rodent brain, enabling visualization of neuroarchitecture. The present work investigates the dose and temporal dependence of brain enhancement after i.v. administration o...

journal_title：Magnetic resonance in medicine

authors： Lee JH,Silva AC,Merkle H,Koretsky AP

更新日期：2005-03-01 00:00:00

abstract：:Recent in vivo 1H MRS studies of muscle oxygen levels by means of myoglobin (Mb) oxygenation have necessitated an investigation of the possible contamination from deoxy-hemoglobin (Hb). To determine the contribution of Hb in these NMR measurements, we studied the NMR visibility of histidyl N-delta proton of Hb in lyse...

journal_title：Magnetic resonance in medicine

authors： Wang DJ,Nioka S,Wang Z,Leigh JS,Chance B

更新日期：1993-12-01 00:00:00

abstract：PURPOSE:To develop and validate a regularization approach of optimizing B1 insensitivity of the quantitative magnetization transfer (qMT) pool-size ratio (F). METHODS:An expression describing the impact of B1 inaccuracies on qMT fitting parameters was derived using a sensitivity analysis. To simultaneously optimize fo...

journal_title：Magnetic resonance in medicine

authors： Boudreau M,Pike GB

更新日期：2018-12-01 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：:A potential relationship between structural compartments in neural tissue and NMR parameters may increase the specificity of MRI in diagnosing diseases. Nevertheless, our understanding of MR of nerves and white matter is limited, particularly the influence of various water compartments on the MR signal is not known. I...

journal_title：Magnetic resonance in medicine

authors： Peled S,Cory DG,Raymond SA,Kirschner DA,Jolesz FA

更新日期：1999-11-01 00:00:00

abstract：:A general analytical framework is presented for the design of birdcage radiofrequency resonators on cylindrical formers having arbitrary cross-sectional shape. The primary objective of such shapes would be to improve the sensitivity of the NMR experiment to noncircular regions of the human anatomy while maintaining fi...

journal_title：Magnetic resonance in medicine

authors： De Zanche N,Yahya A,Vermeulen FE,Allen PS

更新日期：2005-01-01 00:00:00

abstract：:In spin echo imaging, magnetization is assigned to a location defined by its frequency of rotation. In the presence of a static magnetic field inhomogeneity, however, this location does not correspond to the true location of the magnetization. This paper describes a magnetic resonance imaging technique called phase co...

journal_title：Magnetic resonance in medicine

authors： Kim JK,Plewes DB,Henkelman RM

更新日期：1995-04-01 00:00:00

abstract：:A partial saturation method is described for obtaining rapid images of tissue 1H spin-lattice relaxation rates following administration of the paramagnetic contrast agent gadolinium-diethylenetriaminepentaacetate. The paramagnetic contribution to the relaxation rates is proportional to the concentration of contrast ag...

journal_title：Magnetic resonance in medicine

authors： Kennedy SD,Szczepaniak LS,Gibson SL,Hilf R,Foster TH,Bryant RG

更新日期：1994-03-01 00:00:00

abstract：PURPOSE:To develop a method based on fat-water transition region extraction (TREE) for robust fat-water separation and quantification in challenging scenarios, including low signal-to-noise ratio (SNR), fast changing B0 field, and disjointed anatomies. THEORY AND METHODS:In TREE method, the phasor solutions of each pi...

journal_title：Magnetic resonance in medicine

authors： Peng H,Zou C,Cheng C,Tie C,Qiao Y,Wan Q,Lv J,He Q,Liang D,Liu X,Liu W,Zheng H

更新日期：2019-07-01 00:00:00