MR image reconstruction from generalized projections.

abstract：:The detection of free radical reactions in a gelatin sample irradiated by a heavy-ion beam was tested using electron paramagnetic resonance (EPR) spectroscopic and MRI methods. Geometry and the amount of free radical generation in a sample are described. A reaction mixture containing glutathione and a nitroxyl radical...

journal_title：Magnetic resonance in medicine

authors： Matsumoto K,Nagata K,Yamamoto H,Endo K,Anzai K,Aoki I

更新日期：2009-05-01 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：:Proton T2 relaxation and its biexponential components have been determined in rabbit skeletal muscle in the presence and absence of GdDTPA. The effect of GdDTPA, which distributes only in the extracellular space, was greatest in the longer-relaxing T2 component (T22). A 27% reduction in T22 was measured for slow-twitc...

journal_title：Magnetic resonance in medicine

authors： Adzamli IK,Jolesz FA,Bleier AR,Mulkern RV,Sandor T

更新日期：1989-08-01 00:00:00

abstract：:Mathematical models are required to estimate kinetic parameters of [1-(13)C] pyruvate-lactate interconversion from magnetic resonance spectroscopy data. One- or two-way exchange models utilizing a hypothetical approximation to the true arterial input function (AIF), (e.g. an ideal 'box-car' function) have been used pr...

journal_title：Magnetic resonance in medicine

authors： Kazan SM,Reynolds S,Kennerley A,Wholey E,Bluff JE,Berwick J,Cunningham VJ,Paley MN,Tozer GM

更新日期：2013-10-01 00:00:00

abstract：:Acute normovolemic hemodilution (HD) was induced in anesthetized rats to assess the effect of changes in hematocrit (Hct) on signal intensity in T2*-weighted magnetic resonance (MR) images. Other relevant physiological parameters were maintained invariant. Two degrees of HD were induced: mild (Hct reduced from 42.6+/-...

journal_title：Magnetic resonance in medicine

authors： Lin W,Paczynski RP,Celik A,Hsu CY,Powers WJ

更新日期：1998-12-01 00:00:00

abstract：:The authors present their 1-year experience with the use of 3DFT, time-of-flight MR angiography for the evaluation of vascular diseases of the head and neck. Their experience with over 150 patients indicates that this examination may be performed in conjunction with standard spin-echo imaging with only a minimal incre...

journal_title：Magnetic resonance in medicine

authors： Masaryk TJ,Laub GA,Modic MT,Ross JS,Haacke EM

更新日期：1990-05-01 00:00:00

abstract：:Since contrast in magnetic resonance imaging (MRI) is so sensitive to the magnetic relaxation rates of tissue protons, the use of paramagnetic ions to alter contrast in a tissue-specific fashion is an alluring prospect. The influence of these ions on the proton relaxation rates in homogeneous solutions is known to var...

journal_title：Magnetic resonance in medicine

authors： Koenig SH,Brown RD 3rd,Goldstein EJ,Burnett KR,Wolf GL

更新日期：1985-04-01 00:00:00

abstract：:Parallel imaging reconstructions result in spatially varying noise amplification characterized by the g-factor, precluding conventional measurements of noise from the final image. A simple Monte Carlo based method is proposed for all linear image reconstruction algorithms, which allows measurement of signal-to-noise r...

journal_title：Magnetic resonance in medicine

authors： Robson PM,Grant AK,Madhuranthakam AJ,Lattanzi R,Sodickson DK,McKenzie CA

更新日期：2008-10-01 00:00:00

abstract：:Phase-contrast MRI can provide high-resolution angiographic velocity images, especially in conjunction with non-Cartesian k-space sampling. However, acquisitions can be sensitive to errors from artifacts from main magnetic field inhomogeneities and chemical shift from fat. Particularly in body imaging, fat content can...

journal_title：Magnetic resonance in medicine

authors： Johnson KM,Wieben O,Samsonov AA

更新日期：2010-06-01 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：:MRI of hyperpolarized (129)Xe dissolved in pulmonary tissues, and blood has the potential to offer a new tool for regional evaluation of pulmonary gas exchange and perfusion; however, the extremely short T2* and low magnetization density make it difficult to acquire the image. In this study, an ultrashort echo-time se...

journal_title：Magnetic resonance in medicine

authors： Iguchi S,Imai H,Hori Y,Nakajima J,Kimura A,Fujiwara H

更新日期：2013-07-01 00:00:00

abstract：:Quantification of cerebral blood flow using QUIPSSII pulsed arterial spin labeling requires that the QUIPSS saturation delay TI1 is shorter than the natural temporal bolus width. Yet the duration of the bolus of tagged spins entering the region of interest varies during vasoactive stimuli such as gaseous challenges or...

journal_title：Magnetic resonance in medicine

authors： Villien M,Chipon E,Troprès I,Bouvier J,Cantin S,Chechin D,Le Bas JF,Krainik A,Warnking JM

更新日期：2013-06-01 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：:In this high resolution magnetic resonance spectroscopic study of experimental allergic encephalomyelitis (EAE) and Semliki Forest virus (SFV) infection of the Biozzi AB/H mouse, marked increases in the initially low levels of N-trimethyl compounds in the spinal cord were observed during probable demyelinating episode...

journal_title：Magnetic resonance in medicine

authors： Preece NE,Amor S,Baker D,Gadian DG,O'Neill JK,Urenjak J

更新日期：1994-12-01 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：PURPOSE:To verify MR measurements of myocardial extracellular volume fraction (ECV) based on clinically applicable T1-mapping sequences against ECV measurements by radioisotope tracer in pigs and to relate the results to those obtained in volunteers. METHODS:Between May 2016 and March 2017, 8 volunteers (25 ± 4 years,...

journal_title：Magnetic resonance in medicine

authors： Nordlund D,Xanthis C,Bidhult S,Jablonowski R,Kanski M,Kopic S,Carlsson M,Engblom H,Aletras AH,Arheden H

更新日期：2020-02-01 00:00:00

abstract：:A regularized algorithm is presented for localized in vivo shimming. The technique uses first- (X,Y,Z), second- (Z(2), ZX, ZY, X(2)-Y(2), XY), and third-order (Z(3)) shim coils, and is robust when applied to arbitrarily-shaped, as well as off-center, regions of interest (ROIs). A single-shot spiral pulse sequence is u...

journal_title：Magnetic resonance in medicine

authors： Kim DH,Adalsteinsson E,Glover GH,Spielman DM

更新日期：2002-10-01 00:00:00

abstract：:Fucose is believed to be a marker for cancer that may be detectable by the 2D proton NMR (COSY) of human plasma. However, the COSY technique is time consuming and prone to error. These problems may be alleviated by using the SUPERCOSY pulse sequence; this technique shows that there are many other cross peaks in the re...

journal_title：Magnetic resonance in medicine

authors： Phillips PS,Herring FG

更新日期：1990-07-01 00:00:00

abstract：PURPOSE:To develop a 256-channel dense-array electroencephalography (dEEG) sensor net (the Ink-Net) using high-resistance polymer thick film (PTF) technology to improve safety and data quality during simultaneous dEEG/MRI. METHODS:Heating safety was assessed with temperature measurements in an anthropomorphic head pha...

journal_title：Magnetic resonance in medicine

authors： Poulsen C,Wakeman DG,Atefi SR,Luu P,Konyn A,Bonmassar G

更新日期：2017-02-01 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：:This study determines the accuracy and feasibility of using localized spin-lattice (T1) relaxation time measurements from magnetic resonance (MR) images to follow changes in extracellular/intracellular fluid ratios in defined subvolumes of living tissue. A red blood cell suspension was used as a test system and a simp...

journal_title：Magnetic resonance in medicine

authors： Martin MA,Tatton WG,Lemaire C,Armstrong RL

更新日期：1990-07-01 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：:Proton-electron double-resonance imaging (PEDRI) was used to assess renal function by monitoring the flow of the exogenous nitroxide free radical proxyl carboxylic acid (PCA) through normal and injured kidneys in the living rat. Kidney damage was induced by treatment with 2-bromoethylamine (BEA), which provides a well...

journal_title：Magnetic resonance in medicine

authors： Seimenis I,Foster MA,Lurie DJ,Hutchison JM,Whiting PH,Payne S

更新日期：1998-08-01 00:00:00

abstract：:Magnetization transfer experiments using an off-resonance irradiation technique were performed on bovine serum albumin solutions by varying the irradiation frequency and the concentration. A transition of the magnetization transfer spectrum from Lorentzian to Gaussian line shape was observed around the critical concen...

journal_title：Magnetic resonance in medicine

authors： Iino M

更新日期：1994-10-01 00:00:00

abstract：:The presence of macroscopic vessels within the tumor region is a potential confounding factor in MR-based dynamic susceptibility contrast (DSC)-enhanced glioma grading. In order to distinguish between such vessels and the elevated cerebral blood volume (CBV) of brain tumors, we propose a vessel segmentation technique ...

journal_title：Magnetic resonance in medicine

authors： Emblem KE,Due-Tonnessen P,Hald JK,Bjornerud A

更新日期：2009-05-01 00:00:00

abstract：PURPOSE:In this study, an iterative k-t principal component analysis (PCA) algorithm with nonrigid frame-to-frame motion correction is proposed for dynamic contrast-enhanced three-dimensional perfusion imaging. METHODS:An iterative k-t PCA algorithm was implemented with regularization using training data corrected for...

journal_title：Magnetic resonance in medicine

authors： Schmidt JF,Wissmann L,Manka R,Kozerke S

更新日期：2014-07-01 00:00:00

abstract：:This work presents a method that allows for the assessment of 3D murine myocardial motion in vivo at microscopic resolution. Phase-contrast (PC) magnetic resonance imaging (MRI) at 17.6 T was applied to map myocardial motion in healthy mice along three gradient directions. High-resolution velocity maps were acquired a...

journal_title：Magnetic resonance in medicine

authors： Herold V,Mörchel P,Faber C,Rommel E,Haase A,Jakob PM

更新日期：2006-05-01 00:00:00

abstract：:Parallel imaging presents a promising approach for MRI of hyperpolarized nuclei, as the penalty in signal-to-noise ratio typically encountered with (1)H MRI due to a reduction in acquisition time can be offset by an increase in flip angle. The signal-to-noise ratio of hyperpolarized MRI generally exhibits a strong dep...

journal_title：Magnetic resonance in medicine

authors： Deppe MH,Parra-Robles J,Marshall H,Lanz T,Wild JM

更新日期：2011-12-01 00:00:00

abstract：:The purpose of this study was to demonstrate the feasibility of dynamic oxygen-enhanced MRI in a clinical setting. We hypothesized that dynamic oxygen enhancement can reflect the regional diffusing capacity of the lung. Ten patients with pulmonary emphysema and seven healthy volunteers were examined with a respiratory...

journal_title：Magnetic resonance in medicine

authors： Ohno Y,Hatabu H,Takenaka D,Van Cauteren M,Fujii M,Sugimura K

更新日期：2002-06-01 00:00:00

abstract：:Levo-tetrahydropalmatine (l-THP) has shown significant promise in preclinical and clinical studies to treat drug addiction. Pharmacological MRI methods can elucidate the regional cerebral effects of l-THP, but there are potential confounds from the use of general anesthesia. To investigate the possible anesthetic-drug...

journal_title：Magnetic resonance in medicine

authors： Liu X,Li R,Yang Z,Hudetz AG,Li SJ

更新日期：2012-08-01 00:00:00