Maximum entropy and 2DFT NMR images.


:A comparison between contrast and signal-to-noise ratio (SNR), as obtained by both maximum entropy (ME) and 2DFT reconstruction, is reported for NMR images. Our results show that in the ME elaboration the contrast and SNR are generally increased with respect to the 2DFT elaboration. The magnitude of such an increase depends on the ME statistical parameter and also, quite strongly, on the values of contrast and SNR of the 2DFT image.


Magn Reson Med


De Simone BC,De Luca F,Maraviglia B




Has Abstract


1988-11-01 00:00:00












  • Cardiac and respiratory double self-gated cine MRI in the mouse at 7 T.

    abstract::ECG-gated cardiac MRI in the mouse is hindered by many technical difficulties in ECG signal recording inside static and variable high magnetic scanner fields. The present study proposes an alternative robust method of acquiring auto-gated cardiac and respiratory cine images in mouse heart. In our approach, a motion sy...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Hiba B,Richard N,Janier M,Croisille P

    更新日期:2006-03-01 00:00:00

  • Real-time measurements of cellular oxygen consumption, pH, and energy metabolism using nuclear magnetic resonance spectroscopy.

    abstract::Changes in molecular expression or apoptotic behavior, induced by malignant transformation or anticancer treatment, are frequently reflected in cellular metabolism and oxygen consumption. A technique to monitor oxygen consumption, cell physiology, and metabolism noninvasively would provide a better understanding of in...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Pilatus U,Aboagye E,Artemov D,Mori N,Ackerstaff E,Bhujwalla ZM

    更新日期:2001-05-01 00:00:00

  • Simultaneous acquisition of image and navigator slices using CAIPIRINHA for 4D MRI.

    abstract:PURPOSE:Respiratory organ motion is still the major challenge of various image-guided treatments in the abdomen. Dynamic organ motion tracking, necessary for the treatment control, can be performed with volumetric time-resolved MRI that sequentially acquires one image and one navigator slice. Here, a novel imaging meth...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Celicanin Z,Bieri O,Preiswerk F,Cattin P,Scheffler K,Santini F

    更新日期:2015-02-01 00:00:00

  • The effect of B1 field inhomogeneity and the nonselective inversion profile on the kinetics of FAIR-based perfusion MRI.

    abstract::Perfusion imaging with pulsed arterial spin labeling techniques, like flow-sensitive alternating inversion recovery (FAIR), may suffer from inflow of fresh, i.e., unlabeled, spins. Inflow of fresh spins is caused by the arrival of unlabeled spins in the image slice and can lead to underestimation of the perfusion if n...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Schepers J,van Osch MJ,Bartels LW,Heukels SN,Viergever MA,Nicolay K

    更新日期:2005-06-01 00:00:00

  • Improved estimation of velocity and flow rate using regularized three-point phase-contrast velocimetry.

    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

    pub_type: 杂志文章


    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

  • A variability study of regional alveolar oxygen tension measurement in humans using hyperpolarized (3) He MRI.

    abstract:PURPOSE:A systematic study of the short-term and long-term variability of regional alveolar partial pressure of oxygen tension (pA O2 ) measurements using (3) He magnetic resonance imaging was presented. Additionally, the repeatability of the average evaluated pA O2 was compared with that of the standard pulmonary func...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Hamedani H,Kadlecek SJ,Ishii M,Emami K,Kuzma NN,Xin Y,Rossman M,Rizi RR

    更新日期:2013-12-01 00:00:00

  • Flow-suppressed hyperpolarized 13 C chemical shift imaging using velocity-optimized bipolar gradient in mouse liver tumors at 9.4 T.

    abstract:PURPOSE:To optimize and investigate the influence of bipolar gradients for flow suppression in metabolic quantification of hyperpolarized 13 C chemical shift imaging (CSI) of mouse liver at 9.4 T. METHODS:The trade-off between the amount of flow suppression using bipolar gradients and T2* effect from static spins was ...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


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

    更新日期:2017-11-01 00:00:00

  • Comprehensive approach for correction of motion and distortion in diffusion-weighted MRI.

    abstract::Patient motion and image distortion induced by eddy currents cause artifacts in maps of diffusion parameters computed from diffusion-weighted (DW) images. A novel and comprehensive approach to correct for spatial misalignment of DW imaging (DWI) volumes acquired with different strengths and orientations of the diffusi...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Rohde GK,Barnett AS,Basser PJ,Marenco S,Pierpaoli C

    更新日期:2004-01-01 00:00:00

  • On the signal-to-noise ratio benefit of spiral acquisition in diffusion MRI.

    abstract:PURPOSE:Spiral readouts combine several favorable properties that promise superior net sensitivity for diffusion imaging. The purpose of this study is to verify the signal-to-noise ratio (SNR) benefit of spiral acquisition in comparison with current echo-planar imaging (EPI) schemes. METHODS:Diffusion-weighted in vivo...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Lee Y,Wilm BJ,Brunner DO,Gross S,Schmid T,Nagy Z,Pruessmann KP

    更新日期:2021-04-01 00:00:00

  • Image contrast using the secondary and tertiary eigenvectors in diffusion tensor imaging.

    abstract::Diffusion tensor imaging (DTI) is a new imaging modality that can provide unique information on brain white matter anatomy. Measurements of water diffusion constant along multiple axes are fitted to a tensor model, from which the diffusion anisotropy and dominant fiber orientation can be estimated. Even though the ten...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Zhang J,van Zijl PC,Mori S

    更新日期:2006-02-01 00:00:00

  • Multispectral imaging with three-dimensional rosette trajectories.

    abstract::Two-dimensional intersecting k-space trajectories have previously been demonstrated to allow fast multispectral imaging. Repeated sampling of k-space points leads to destructive interference of the signal coming from the off-resonance spectral peaks; on-resonance data reconstruction yields images of the on-resonance p...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Bucholz EK,Song J,Johnson GA,Hancu I

    更新日期:2008-03-01 00:00:00

  • Hyperpolarized 13C NMR detects rapid drug-induced changes in cardiac metabolism.

    abstract:PURPOSE:The diseased myocardium lacks metabolic flexibility and responds to stimuli differently compared with healthy hearts. Here, we report the use of hyperpolarized 13C NMR spectroscopy to detect sudden changes in cardiac metabolism in isolated, perfused rat hearts in response to adrenergic stimulation. METHODS:Met...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Khemtong C,Carpenter NR,Lumata LL,Merritt ME,Moreno KX,Kovacs Z,Malloy CR,Sherry AD

    更新日期:2015-08-01 00:00:00

  • Cellular imaging and texture analysis distinguish differences in cellular dynamics in mouse brain tumors.

    abstract:PURPOSE:The heterogeneous tumor cell population and dynamic microenvironment within a tumor lead to regional variations in cell proliferation, migration, and differentiation. In this work, MRI and optical projection tomography were used to examine and compare the redistribution of a cellular label in two mouse glioma m...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Gazdzinski LM,Nieman BJ

    更新日期:2014-04-01 00:00:00

  • A one-step biomarker quantification methodology for DCE-MRI of adnexal masses: Capturing kinetic pattern from early to late enhancement.

    abstract:PURPOSE:To develop a one-step quantification approach that accounts for joint preprocessing and quantification of whole-range kinetics (early and late-phase washout) of dynamic contrast-enhanced (DCE) MRI of indeterminate adnexal masses. METHODS:Preoperative DCE-MRI of 43 (24 benign, 19 malignant) sonographically inde...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Fathi Kazerooni A,Nabil M,Haghighat Khah H,Parviz S,Gity M,Saligheh Rad H

    更新日期:2018-02-01 00:00:00

  • Automatic selection of mask and arterial phase images for temporally resolved MR digital subtraction angiography.

    abstract::For time-resolved background-subtracted contrast-enhanced magnetic resonance angiography, the bright and sparse arterial signal allows unique identification of contrast bolus arrival in the arteries. This article presents an automatic filtering algorithm using such arterial characterization for selecting arterial phas...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Kim J,Prince MR,Zabih R,Bezanson J,Watts R,Erel HE,Wang Y

    更新日期:2002-12-01 00:00:00

  • Wideband myocardial perfusion pulse sequence for imaging patients with a cardiac implantable electronic device.

    abstract:PURPOSE:To develop a wideband cardiac perfusion pulse sequence and test whether it is capable of suppressing image artifacts in patients with a cardiac implantable electronic device (CIED), while not exceeding the specific absorption rate (SAR) limit (2.0 W/kg). METHODS:A wideband perfusion pulse sequence was develope...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Hong K,Collins JD,Knight BP,Carr JC,Lee DC,Kim D

    更新日期:2019-02-01 00:00:00

  • 3D coronary artery imaging with phase reordering for improved scan efficiency.

    abstract::Three-dimensional (3D) coronary imaging has the potential to overcome problems resulting from vessel tortuosity and to reduce partial volume effects. With these techniques, however, acquisition times are long and respiratory motion artifacts problematical. This work describes the development of a method that applies p...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Jhooti P,Keegan J,Gatehouse PD,Collins S,Rowe A,Taylor AM,Firmin DN

    更新日期:1999-03-01 00:00:00

  • Use of high temperature superconductor in a receiver coil for magnetic resonance imaging.

    abstract::A planar YBa2Cu3Ox (YBCO) coil has been used as a pick-up coil in a nuclear magnetic resonance imager. It was found that the quality factor (Q) of the YBCO coil was greater than its copper counterpart by approaching 50% even in a field of 0.15 T. The Q of the copper coil at 77 K and in a field of 0.15 T was 1200 while...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Hall AS,Alford NM,Button TW,Gilderdale DJ,Gehring KA,Young IR

    更新日期:1991-08-01 00:00:00

  • Black-blood native T1 mapping: Blood signal suppression for reduced partial voluming in the myocardium.

    abstract:PURPOSE:To study the feasibility of black-blood contrast in native T1 mapping for reduction of partial voluming at the blood-myocardium interface. METHODS:A saturation pulse prepared heart-rate-independent inversion recovery (SAPPHIRE) T1 mapping sequence was combined with motion-sensitized driven-equilibrium (MSDE) b...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Weingärtner S,Meßner NM,Zöllner FG,Akçakaya M,Schad LR

    更新日期:2017-08-01 00:00:00

  • In vivo differentiation of two vessel wall layers in lower extremity peripheral vein bypass grafts: application of high-resolution inner-volume black blood 3D FSE.

    abstract::Lower extremity peripheral vein bypass grafts (LE-PVBG) imaged with high-resolution black blood three-dimensional (3D) inner-volume (IV) fast spin echo (FSE) MRI at 1.5 Tesla possess a two-layer appearance in T1W images while only the inner layer appears visible in the corresponding T2W images. This study quantifies t...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Mitsouras D,Owens CD,Conte MS,Ersoy H,Creager MA,Rybicki FJ,Mulkern RV

    更新日期:2009-09-01 00:00:00

  • Determination of extracellular/intracellular fluid ratios from magnetic resonance images: accuracy, feasibility, and implementation.

    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

    pub_type: 杂志文章


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

    更新日期:1990-07-01 00:00:00

  • Iterative correction of RF envelope distortion with GRATER-measured waveforms.

    abstract:PURPOSE:To develop and evaluate a method for RF envelope correction without extra hardware or synchronization. METHODS:Transmitted RF waveforms are measured through a simple pulse sequence called the gradient reversal approach to evaluate RF (GRATER). The measured RF waveforms are used to compute predistorted RF wavef...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Landes VL,Nayak KS

    更新日期:2020-01-01 00:00:00

  • Rapid radiofrequency field mapping in vivo using single-shot STEAM MRI.

    abstract::Higher field strengths entail less homogeneous RF fields. This may influence quantitative MRI and MRS. A method for rapidly mapping the RF field in the human head with minimal distortion was developed on the basis of a single-shot stimulated echo acquisition mode (STEAM) sequence. The flip angle of the second RF pulse...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Helms G,Finsterbusch J,Weiskopf N,Dechent P

    更新日期:2008-09-01 00:00:00

  • Systematic analysis of the intravoxel incoherent motion threshold separating perfusion and diffusion effects: Proposal of a standardized algorithm.

    abstract:PURPOSE:To systematically evaluate the dependence of intravoxel-incoherent-motion (IVIM) parameters on the b-value threshold separating the perfusion and diffusion compartment, and to implement and test an algorithm for the standardized computation of this threshold. METHODS:Diffusion weighted images of the upper abdo...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Wurnig MC,Donati OF,Ulbrich E,Filli L,Kenkel D,Thoeny HC,Boss A

    更新日期:2015-11-01 00:00:00

  • Eddy current correction in diffusion-weighted imaging using pairs of images acquired with opposite diffusion gradient polarity.

    abstract::In echo-planar-based diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI), the evaluation of diffusion parameters such as apparent diffusion coefficients and anisotropy indices is affected by image distortions that arise from residual eddy currents produced by the diffusion-sensitizing gradients. Correc...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Bodammer N,Kaufmann J,Kanowski M,Tempelmann C

    更新日期:2004-01-01 00:00:00

  • An automated tool for cortical feature analysis: Application to differences on 7 Tesla T2* -weighted images between young and older healthy subjects.

    abstract:PURPOSE:High field T2* -weighted MR images of the cerebral cortex are increasingly used to study tissue susceptibility changes related to aging or pathologies. This paper presents a novel automated method for the computation of quantitative cortical measures and group-wise comparison using 7 Tesla T2* -weighted magnitu...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Doan NT,van Rooden S,Versluis MJ,Buijs M,Webb AG,van der Grond J,van Buchem MA,Reiber JHC,Milles J

    更新日期:2015-07-01 00:00:00

  • Sensitivity of feedback-enhanced MRI contrast to macroscopic and microscopic field variations.

    abstract::Nonlinear feedback interactions have been shown to amplify contrast due to small differences in resonance frequency arising from microscopic susceptibility variations. Determining whether the selectivity of feedback-based contrast enhancement for small resonance frequency variations remains valid even in the presence ...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Huang SY,Yang SS,Lin YY

    更新日期:2009-04-01 00:00:00

  • Anisotropy of NMR properties of tissues.

    abstract::Orientational anisotropy of T2 and T1 relaxation times, diffusion, and magnetization transfer has been investigated for six different tissues: tendon, cartilage, kidney, muscle, white matter, and optic nerve. Relaxation anisotropy was observed for tendon and cartilage, and diffusional anisotropy was measured in kidney...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Henkelman RM,Stanisz GJ,Kim JK,Bronskill MJ

    更新日期:1994-11-01 00:00:00

  • A computer simulation program for MR imaging: application to RF and static magnetic field imperfections.

    abstract::A computer simulation program capable of demonstrating various artifacts, such as image distortion caused by metallic implants in MR imaging, is presented. The structure of the program allows for the implementation of various imaging situations as long as spins only experience weak interaction, i.e., the Bloch equatio...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Olsson MB,Wirestam R,Persson BR

    更新日期:1995-10-01 00:00:00

  • Free-breathing cine MRI.

    abstract::Standard MRI cine exams for the study of cardiac function are segmented over several heartbeats and thus require a breath-hold to minimize breathing motion artifacts, which is a current limitation of this approach. The purpose of this study was to develop a method for the measurement and correction of respiratory moti...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Leung AO,Paterson I,Thompson RB

    更新日期:2008-09-01 00:00:00