NMR investigation of hydroxyethyl starch-induced aggregation of human erythrocytes.

abstract：:If magnetic resonance spectroscopy (MRS) is to become a useful tool in clinical medicine, it will be necessary to find reliable methods for analyzing and classifying MRS data. Automated methods are desirable because they can remove user bias and can deal with large amounts of data, allowing the use of all the availabl...

journal_title：Magnetic resonance in medicine

authors： Tate AR,Watson D,Eglen S,Arvanitis TN,Thomas EL,Bell JD

更新日期：1996-06-01 00:00:00

abstract：:Multislice MR images obtained using a fast spin-echo (FSE) readout are strongly affected by magnetization transfer (MT) effects, which will cause a decrease in the observed longitudinal relaxation times for tissues with a large bound water component. This is pertinent for FSE-based inversion-recovery (IR) sequences, a...

journal_title：Magnetic resonance in medicine

authors： Meara SJ,Barker GJ

更新日期：2007-10-01 00:00:00

abstract：:The idea of using parallel imaging to shorten the acquisition time by the simultaneous use of multiple receive coils can be adapted for the parallel transmission of a spatially-selective multidimensional RF pulse. As in data acquisition, a multidimensional RF pulse follows a certain k-space trajectory. Shortening this...

journal_title：Magnetic resonance in medicine

authors： Katscher U,Börnert P,Leussler C,van den Brink JS

更新日期：2003-01-01 00:00:00

abstract：:The Shinnar-Le Roux (SLR) radiofrequency (RF) pulse design algorithm is widely used for designing slice-selective RF pulses due to its intuitiveness, optimality, and speed. SLR is limited, however, in that it is only capable of designing one-dimensional pulses played along constant gradients. We present a nonuniform S...

journal_title：Magnetic resonance in medicine

authors： Grissom WA,McKinnon GC,Vogel MW

更新日期：2012-09-01 00:00:00

abstract：:Using a 32-echo imaging pulse sequence, T2 relaxation decay curves were acquired from five white- and six gray-matter brain structures outlined in 12 normal volunteers. The water contents of white and gray matter were 0.71 (0.01) and 0.83 (0.03) g/ml, respectively. All white-matter structures had significantly higher ...

journal_title：Magnetic resonance in medicine

authors： Whittall KP,MacKay AL,Graeb DA,Nugent RA,Li DK,Paty DW

更新日期：1997-01-01 00:00:00

abstract：:The application of spectroscopy techniques to the study of normal and pathological tissue is currently limited by the difficulties of acquiring precisely localized spectra and analyzing the resulting, relatively low signal-to-noise data. Interpretation of multivoxel spectroscopy data is greatly facilitated by estimati...

journal_title：Magnetic resonance in medicine

authors： Nelson SJ,Vigneron DB,Brown TR

更新日期：1992-05-01 00:00:00

abstract：:Parallel magnetic resonance imaging (pMRI) using multichannel receiver coils has emerged as an effective tool to reduce imaging time in various applications. However, the issue of accurate estimation of coil sensitivities has not been fully addressed, which limits the level of speed enhancement achievable with the tec...

journal_title：Magnetic resonance in medicine

authors： Ying L,Sheng J

更新日期：2007-06-01 00:00:00

abstract：:A simple iterative algorithm, termed deconvolution-interpolation gridding (DING), is presented to address the problem of reconstructing images from arbitrarily-sampled k-space. The new algorithm solves a sparse system of linear equations that is equivalent to a deconvolution of the k-space with a small window. The dec...

journal_title：Magnetic resonance in medicine

authors： Gabr RE,Aksit P,Bottomley PA,Youssef AB,Kadah YM

更新日期：2006-12-01 00:00:00

abstract：:Diffusion tensor imaging enables in vivo investigation of tissue cytoarchitecture through parameter contrasts sensitive to water diffusion barriers at the micrometer level. Parameters are derived through an estimation process that is susceptible to noise and artifacts. Estimated parameters (e.g., fractional anisotropy...

journal_title：Magnetic resonance in medicine

authors： Lauzon CB,Crainiceanu C,Caffo BC,Landman BA

更新日期：2013-03-01 00:00:00

abstract：:Magnetic resonance (MR) imaging and relaxation time measurements of bioresorbable implants made of polylactic acid (PLA), as well as the surrounding tissues, were carried out over a period of 6 months to monitor the implant state and the body's responses, and to determine how these processes are reflected in MR data. ...

journal_title：Magnetic resonance in medicine

authors： Stroman PW,Dorvil JC,Marois Y,Poddevin N,Guidoin R

更新日期：1999-07-01 00:00:00

abstract：PURPOSE:To investigate a computationally efficient method for optimizing the Cramér-Rao Lower Bound (CRLB) of quantitative sequences without using approximations or an analytical expression of the signal. METHODS:Automatic differentiation was applied to Bloch simulations and used to optimize several quantitative seque...

journal_title：Magnetic resonance in medicine

authors： Lee PK,Watkins LE,Anderson TI,Buonincontri G,Hargreaves BA

更新日期：2019-10-01 00:00:00

abstract：PURPOSE:Intracranial and intraspinal compliance are parameters of interest in the diagnosis and prediction of treatment outcome in patients with normal pressure hydrocephalus and other forms of communicating hydrocephalus. A noninvasive method to estimate the spinal cerebrospinal fluid (CSF) pulse wave velocity (PWV) a...

journal_title：Magnetic resonance in medicine

authors： Sonnabend K,Brinker G,Maintz D,Bunck AC,Weiss K

更新日期：2021-01-01 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：:Passive MR tracking of catheters and guidewires is usually done by dynamically imaging a single thick slab, subtracting a baseline image, and combining the result with a previously acquired MR angiogram. In the in vitro and in vivo experiments reported here, it is demonstrated that this approach may be greatly simplif...

journal_title：Magnetic resonance in medicine

authors： Bakker CJ,Bos C,Weinmann HJ

更新日期：2001-01-01 00:00:00

abstract：:For clinical 31P MR spectroscopic imaging (MRSI) studies, where signal averaging is necessary, some improvement of sensitivity and spatial response function may be achieved by acquiring data over a spherical k-space volume and varying the number of averages acquired in proportion to the desired spatial filter. Eight d...

journal_title：Magnetic resonance in medicine

authors： Hugg JW,Maudsley AA,Weiner MW,Matson GB

更新日期：1996-09-01 00:00:00

abstract：:Quantification of peak velocity is important in the assessment of stenotic flow jets in patients with congenital heart disease. Phase-contrast magnetic resonance underestimates peak velocities. Hence, clinically Doppler ultrasound is used as the reference standard for assessing stenoses. It is possible to accurately m...

journal_title：Magnetic resonance in medicine

authors： Steeden JA,Jones A,Pandya B,Atkinson D,Taylor AM,Muthurangu V

更新日期：2012-06-01 00:00:00

abstract：PURPOSE:To present a double diffusion encoding MRI sequence on a clinical scanner to analyze micro-structure and micro-vasculature of tumors. METHODS:The sequence was tested on phantoms, asparaguses, and 2 tumors allografts in a rodent. Results were analyzed using an adapted VERDICT model to estimate microstructural p...

journal_title：Magnetic resonance in medicine

authors： Duchêne G,Abarca-Quinones J,Leclercq I,Duprez T,Peeters F

更新日期：2020-04-01 00:00:00

abstract：PURPOSE:Phosphorus spectroscopy (31 P-MRS) is a proven method to probe cardiac energetics. Studies typically report the phosphocreatine (PCr) to adenosine triphosphate (ATP) ratio. We focus on another 31 P signal: inorganic phosphate (Pi), whose chemical shift allows computation of myocardial pH, with Pi/PCr providing ...

journal_title：Magnetic resonance in medicine

authors： Apps A,Valkovič L,Peterzan M,Lau JYC,Hundertmark M,Clarke W,Tunnicliffe EM,Ellis J,Tyler DJ,Neubauer S,Rider OJ,Rodgers CT,Schmid AI

更新日期：2021-03-01 00:00:00

abstract：:Calibration of the spatial sensitivity functions of coil arrays is a crucial element in parallel magnetic resonance imaging (PMRI). The most common approach has been to measure coil sensitivities directly using one or more low-resolution images acquired before or after accelerated data acquisition. However, since it i...

journal_title：Magnetic resonance in medicine

authors： McKenzie CA,Yeh EN,Ohliger MA,Price MD,Sodickson DK

更新日期：2002-03-01 00:00:00

abstract：:Using a material that already is in widespread use in humans, India ink, the first EPR measurements in a human have been made, using the India ink in a pre-existing tattoo. The EPR spectra of India ink are very sensitive to the partial pressure of oxygen (pO2), thereby making it feasible to use this approach to measur...

journal_title：Magnetic resonance in medicine

authors： Swartz HM,Liu KJ,Goda F,Walczak T

更新日期：1994-02-01 00:00:00

abstract：PURPOSE:To investigate whether saturation using existing methods developed for 3T imaging is feasible for clinical perfusion imaging at 7T, and to propose a new design of saturation pulse train for first-pass myocardial perfusion imaging at 7T. METHODS:The new design of saturation pulse train consists of four hyperbol...

journal_title：Magnetic resonance in medicine

authors： Tao Y,Hess AT,Keith GA,Rodgers CT,Liu A,Francis JM,Neubauer S,Robson MD

更新日期：2015-04-01 00:00:00

abstract：:A cerebrospinal fluid (CSF)-suppressed flow-attenuated inversion recovery (FLAIR) double-shot diffusion echo-planar imaging (EPI) sequence was developed and used, along with a non-CSF-suppressed version of the sequence, to determine the extent of the contribution of CSF partial-volume averaging to the apparent diffusi...

journal_title：Magnetic resonance in medicine

authors： Falconer JC,Narayana PA

更新日期：1997-01-01 00:00:00

abstract：PURPOSE:In conventional three-dimensional magnetic resonance elastography, motion encoding gradients (MEGs) synchronized to a mechanical excitation are applied separately in each direction to encode tissue displacement generated by the corresponding waves. This requires long acquisition times that introduce errors due ...

journal_title：Magnetic resonance in medicine

authors： Nir G,Sahebjavaher RS,Sinkus R,Salcudean SE

更新日期：2015-04-01 00:00:00

abstract：:A modified Look-Locker acquisition using saturation recovery (MLLSR) for breath-held myocardial T(1) mapping is presented. Despite its reduced dynamic range, saturation recovery enables substantially higher imaging efficiency than conventional inversion recovery T(1) mapping because it does not require time for magnet...

journal_title：Magnetic resonance in medicine

authors： Song T,Stainsby JA,Ho VB,Hood MN,Slavin GS

更新日期：2012-03-01 00:00:00

abstract：:The mechanics of the macrocirculation are examined as a basis for imaging blood flow within the system. The macrocirculation is defined as that part of the circulation in which inertial forces are not negligible compared to viscous forces and as such in human subjects comprises the heart and large blood vessels. Becau...

journal_title：Magnetic resonance in medicine

authors： Caro CG,Parker KH

更新日期：1990-05-01 00:00:00

abstract：:This paper describes a technique for characterizing the gradient subsystem of a magnetic resonance (MR) system. The technique uses a Fourier-transform analysis to directly measure the k-space trajectory produced by an arbitrary gradient waveform. In addition, the method can be easily extended to multiple dimensions an...

journal_title：Magnetic resonance in medicine

authors： Alley MT,Glover GH,Pelc NJ

更新日期：1998-04-01 00:00:00

abstract：PURPOSE:The objective of this study was to determine whether a sodium phased array would improve sodium breast MRI at 3 T. The secondary objective was to create acceptable proton images with the sodium phased array in place. METHODS:A novel composite array for combined proton/sodium 3 T breast MRI is compared with a c...

journal_title：Magnetic resonance in medicine

authors： Kaggie JD,Hadley JR,Badal J,Campbell JR,Park DJ,Parker DL,Morrell G,Newbould RD,Wood AF,Bangerter NK

更新日期：2014-06-01 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:Magnetization transfer in white matter (WM) causes biexponential relaxation, but most quantitative T1 measurements fit data assuming monoexponential relaxation. The resulting monoexponential T1 estimate varies based on scan parameters and represents a source of variation between studies, especially at high fiel...

journal_title：Magnetic resonance in medicine

authors： Rioux JA,Levesque IR,Rutt BK

更新日期：2016-06-01 00:00:00

abstract：PURPOSE:This study aims to (i) develop a new high-speed MRI approach by implementing correlation imaging in wavelet-space, and (ii) demonstrate the ability of wavelet-space correlation imaging to image human anatomy with involuntary or physiological motion. METHODS:Correlation imaging is a high-speed MRI framework in ...

journal_title：Magnetic resonance in medicine

authors： Li Y,Wang H,Tkach J,Roach D,Woods J,Dumoulin C

更新日期：2015-12-01 00:00:00