Hypercarbia-induced changes in cerebral blood volume in the cat: a 1H MRI and intravascular contrast agent study.

abstract：:A MultiEcho Segmented EPI with z-shimmed BAckground gradient Compensation (MESBAC) pulse sequence is proposed and validated for functional MRI (fMRI) study in regions suffering from severe susceptibility artifacts. This sequence provides an effective tradeoff between spatial and temporal resolution and reduces image d...

journal_title：Magnetic resonance in medicine

authors： Li Z,Wu G,Zhao X,Luo F,Li SJ

更新日期：2002-08-01 00:00:00

abstract：:A receive-only phased-array coil was designed to image the lower extremities. The array consists of four volume coils placed on two cylindrical formers. The coil array has the ability to image both legs simultaneously over a 40 cm longitudinal field of view (FOV). Experiments using phantoms show an increase in signal-...

journal_title：Magnetic resonance in medicine

authors： Brown R,Mareyam A,Reid E,Wang Y

更新日期：2004-03-01 00:00:00

abstract：PURPOSE:To accelerate whole-heart three-dimension MR angiography (MRA) by using a variable-density Poisson-disc undersampling pattern and a compressed sensing (CS) reconstruction algorithm, and compare the results with sensitivity encoding (SENSE). METHODS:For whole-heart MRA, a prospective variable-density Poisson-di...

journal_title：Magnetic resonance in medicine

authors： Moghari MH,Uecker M,Roujol S,Sabbagh M,Geva T,Powell AJ

更新日期：2018-02-01 00:00:00

abstract：:A new model of compartmentalized relaxation--that which occurs for spins (protons) exchanging between compartments of different relaxation rates--is presented. This model generalizes previous ones by allowing spatially dependent relaxation within compartments. Solutions for the diffusion-Bloch equations are found via ...

journal_title：Magnetic resonance in medicine

authors： Barsky D,Pütz B,Schulten K

更新日期：1997-05-01 00:00:00

abstract：:A single slice of z-magnetization is used to generate high-speed images. The slice selection step is achieved using two sin-sinc pulses. This procedure eliminates the need for continual slice gradient reversal, a requirement for the FLASH technique. The RAPID imaging method has less inherent T1 and/or T2 dependence th...

journal_title：Magnetic resonance in medicine

authors： Brooks WM,Brereton IM,Doddrell DM

更新日期：1987-08-01 00:00:00

abstract：:High-field MRI scanners are, in principle, well suited for mouse studies; however, many high-field magnets employ a vertical design that may influence the physiological state of the rodent. The purpose of this study was to investigate the orthostatic response of cerebral blood flow (CBF) in mice during a prolonged MR ...

journal_title：Magnetic resonance in medicine

authors： Foley LM,Hitchens TK,Kochanek PM,Melick JA,Jackson EK,Ho C

更新日期：2005-10-01 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：: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：: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 a method for retrospective artifact elimination of MRS data. This retrospective method was based on an approach that combines jackknife analyses with the correlation of spectral windows, and therefore termed "JKC." METHODS:Twelve healthy volunteers performed 3 separate measurement protocols using a ...

journal_title：Magnetic resonance in medicine

authors： Tapper S,Tisell A,Helms G,Lundberg P

更新日期：2019-04-01 00:00:00

abstract：PURPOSE:The purpose of the present study was to apply noninvasive methods for monitoring regeneration and mechanical properties of tissue-engineered cartilage in vivo at different growth stages using MR elastography (MRE). METHODS:Three types of scaffolds, including silk, collagen, and gelatin seeded by human mesenchy...

journal_title：Magnetic resonance in medicine

authors： Khalilzad-Sharghi V,Han Z,Xu H,Othman SF

更新日期：2016-03-01 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:We incorporate simultaneous multislice (SMS) acquisition into MR fingerprinting (MRF) to accelerate the MRF acquisition. METHODS:The t-Blipped SMS-MRF method is achieved by adding a Gz blip before each data acquisition window and balancing it with a Gz blip of opposing polarity at the end of each TR. Thus the ...

journal_title：Magnetic resonance in medicine

authors： Ye H,Ma D,Jiang Y,Cauley SF,Du Y,Wald LL,Griswold MA,Setsompop K

更新日期：2016-05-01 00:00:00

abstract：PURPOSE:Within multiple sclerosis (MS) lesions iron is present in chronically activated microglia. Thus, iron detection with MRI might provide a biomarker for chronic inflammation within lesions. Here, we examine contributions of iron and myelin to magnetic susceptibility of lesions on quantitative susceptibility mappi...

journal_title：Magnetic resonance in medicine

authors： Wisnieff C,Ramanan S,Olesik J,Gauthier S,Wang Y,Pitt D

更新日期：2015-08-01 00:00:00

abstract：:Accurate quantification of myocardial perfusion remains challenging due to saturation of the arterial input function at high contrast concentrations. A method for estimating the arterial input function directly from tissue curves in the myocardium that avoids these difficulties is presented. In this constrained altern...

journal_title：Magnetic resonance in medicine

authors： Fluckiger JU,Schabel MC,DiBella EV

更新日期：2011-08-01 00:00:00

abstract：:Dextran-magnetite, a superparamagnetic compound, is a powerful relaxation reagent for sodium. Administered intravenously, it is confined mainly to the vasculature and eliminates the signal from plasma sodium, a significant component of the tissue sodium signal. Applications of dextran-magnetite for in vivo sodium imag...

journal_title：Magnetic resonance in medicine

authors： Summers RM,Joseph PM,Renshaw PF,Kundel HL

更新日期：1988-12-01 00:00:00

abstract：PURPOSE:Dynamic phosphorus MR spectroscopic imaging (31 P-MRSI) experiments require temporal resolution on the order of seconds to concurrently assess different muscle groups. A highly accelerated pulse sequence combining flyback echo-planar spectroscopic imaging (EPSI) and compressed sensing was developed and tested i...

journal_title：Magnetic resonance in medicine

authors： Santos-Díaz A,Harasym D,Noseworthy MD

更新日期：2019-06-01 00:00:00

abstract：:A 3D sequence for dynamic susceptibility imaging is proposed which combines echo-shifting principles (such as PRESTO), sensitivity encoding (SENSE), and partial-Fourier acquisition. The method uses a moderate SENSE factor of 2 and takes advantage of an alternating partial k-space acquisition in the "slow" phase encode...

journal_title：Magnetic resonance in medicine

authors： Klarhöfer M,Dilharreguy B,van Gelderen P,Moonen CT

更新日期：2003-10-01 00:00:00

abstract：:Wavelet packet analysis is a mathematical transformation that can be used to post-process images, for example, to remove image noise ("denoising"). At a very low signal-to-noise ratio (SNR <5), standard magnitude magnetic resonance images have skewed Rician noise statistics that degrade denoising performance. Since th...

journal_title：Magnetic resonance in medicine

authors： Wood JC,Johnson KM

更新日期：1999-03-01 00:00:00

abstract：PURPOSE:This work describes the construction and evaluation of a bilateral 32-channel receive array for breast imaging at 7T. METHODS:The receive array consisted of 32 receive coils, placed on two 3D-printed hemispherical formers. Each side of the receive array consisted of 16 receive loops, each loop having a corresp...

journal_title：Magnetic resonance in medicine

authors： Del Bosque R,Cui J,Ogier S,Cheshkov S,Dimitrov IE,Malloy C,Wright SM,McDougall M

更新日期：2021-01-01 00:00:00

abstract：:The absolute partial pressure of oxygen (pO(2)) in the mammary gland pad and femoral muscle of female mice was measured using EPR oximetry at 700 MHz. A small quantity of lithium phthalocyanine (LiPc) crystals was implanted in both mammary and femoral muscle tissue of female C3H mice. Subsequent EPR measurements were ...

journal_title：Magnetic resonance in medicine

authors： Matsumoto A,Matsumoto S,Sowers AL,Koscielniak JW,Trigg NJ,Kuppusamy P,Mitchell JB,Subramanian S,Krishna MC,Matsumoto K

更新日期：2005-12-01 00:00:00

abstract：PURPOSE:MR elastography (MRE) of the brain is being explored as a biomarker of neurodegenerative disease such as dementia. However, MRE measures for healthy brain have varied widely. Differing wave delivery methodologies may have influenced this, hence finite element-based simulations were performed to explore this pos...

journal_title：Magnetic resonance in medicine

authors： McGrath DM,Ravikumar N,Beltrachini L,Wilkinson ID,Frangi AF,Taylor ZA

更新日期：2017-07-01 00:00:00

abstract：PURPOSE:A direct method of imaging neural activity was simulated to determine typical signal sizes. METHODS:An active bidomain finite-element model was used to estimate approximate perturbations in MR phase data as a result of neural tissue activity, and when an external MR electrical impedance tomography imaging curr...

journal_title：Magnetic resonance in medicine

authors： Sadleir RJ,Fu F,Chauhan M

更新日期：2019-01-01 00:00:00

abstract：:The regional cerebral blood flow (rCBF) values determined using continuous arterial spin labeling (CASL) are subject to several sources of variability, including natural physiologic variations, sensitivity to the input parameters, and the use of different quantification models. To date, a thorough analysis of the impa...

journal_title：Magnetic resonance in medicine

authors： Steger TR,White RA,Jackson EF

更新日期：2005-04-01 00:00:00

abstract：:A new decoupling sequence, PBAR, is described for broadband heteronuclear decoupling in vivo in humans at 1.5T. The sequence uses non-adiabatic, frequency- and amplitude-modulated inversion pulses designed to minimize decoupling sidebands at low applied gammaB(2) RF field levels and to cover only the narrow range of r...

journal_title：Magnetic resonance in medicine

authors： Barker PB,Golay X,Artemov D,Ouwerkerk R,Smith MA,Shaka AJ

更新日期：2001-02-01 00:00:00

abstract：PURPOSE:Quantitative evaluation of dynamic contrast enhanced MRI (DCE-MRI) allows for estimating perfusion, vessel permeability, and tissue volume fractions by fitting signal intensity curves to pharmacokinetic models. These compart mental models assume rapid equilibration of contrast agent within each voxel. However, ...

journal_title：Magnetic resonance in medicine

authors： Woodall RT,Barnes SL,Hormuth DA 2nd,Sorace AG,Quarles CC,Yankeelov TE

更新日期：2018-07-01 00:00:00

abstract：:Multichannel transmission has the potential to improve many aspects of MRI through a new paradigm in excitation. In this study, multichannel transmission is used to address the effects that variations in B(0) homogeneity have on fat-saturation preparation through the use of the frequency, phase, and amplitude degrees ...

journal_title：Magnetic resonance in medicine

authors： Heilman JA,Derakhshan JD,Riffe MJ,Gudino N,Tkach J,Flask CA,Duerk JL,Griswold MA

更新日期：2012-08-01 00:00:00

abstract：:An approach to efficiently measure three-dimensional velocity vector fields and turbulent kinetic energy of blood flow is presented. Multipoint phase-contrast imaging is used in combination with Bayesian analysis to map both mean and fluctuating velocities over a large dynamic range and for practically relevant signal...

journal_title：Magnetic resonance in medicine

authors： Binter C,Knobloch V,Manka R,Sigfridsson A,Kozerke S

更新日期：2013-05-01 00:00:00

abstract：PURPOSE:To investigate whether nonlinear dimensionality reduction improves unsupervised classification of (1) H MRS brain tumor data compared with a linear method. METHODS:In vivo single-voxel (1) H magnetic resonance spectroscopy (55 patients) and (1) H magnetic resonance spectroscopy imaging (MRSI) (29 patients) dat...

journal_title：Magnetic resonance in medicine

authors： Yang G,Raschke F,Barrick TR,Howe FA

更新日期：2015-09-01 00:00:00

abstract：:In this study we utilized manganese-enhanced MRI (MEMRI) to evaluate the in vivo transneuronal efficiency of manganese ion (Mn(2+)) movement as a means to assess overall changes in neuronal function. We designated this extension the manganese transfer index (MTI) value. To evaluate the MTI value as an index of transne...

journal_title：Magnetic resonance in medicine

authors： Serrano F,Deshazer M,Smith KD,Ananta JS,Wilson LJ,Pautler RG

更新日期：2008-07-01 00:00:00