Effect of feature extraction for brain tumor classification based on short echo time 1H MR spectra.

abstract：:Metallic particles have shaped the use of magnetic resonance imaging (MRI) for molecular and cellular imaging. Although these particles have generally been developed for extracellular residence, either as blood pool contrast agents or targeted contrast agents, the coopted use of these particles for intracellular label...

journal_title：Magnetic resonance in medicine

authors： Shapiro EM

更新日期：2015-01-01 00:00:00

abstract：:Spiral k-space magnetic resonance spectroscopic imaging (MRSI) requires high performance from gradient hardware systems. During the readout phase, oscillating gradients are continuously played out, which can cause undesired effects. These effects on the quality of SI data are non-intuitive because of their time-varyin...

journal_title：Magnetic resonance in medicine

authors： Kim DH,Spielman DM

更新日期：2006-07-01 00:00:00

abstract：PURPOSE:Coil-by-coil reconstruction methods are followed by coil combination to obtain a single image representing a spin density map. Typical coil combination methods, such as square-root sum-of-squares and adaptive coil combining, yield images that exhibit spatially varying modulation of image intensity. Existing pra...

journal_title：Magnetic resonance in medicine

authors： Gol Gungor D,Potter LC

更新日期：2016-02-01 00:00:00

abstract：:The goal of this work was to develop and evaluate a numerically optimized inversion pulse to be used with a homonuclear editing sequence to measure human cerebral GABA in vivo at 4.1 T in the occipital lobe. The optimized pulse was constructed using pallindromic symmetry with 30 pulses and 29 delays. The optimized pul...

journal_title：Magnetic resonance in medicine

authors： Hetherington HP,Newcomer BR,Pan JW

更新日期：1998-01-01 00:00:00

abstract：PURPOSE:Establishing a high-resolution non-ECG-gated first-pass perfusion (FPP) cardiac MRI technique may improve accessibility and diagnostic capability of FPP imaging. We propose a non-ECG-gated FPP imaging technique using continuous magnetization-driven golden-angle radial acquisition. The main purpose of this preli...

journal_title：Magnetic resonance in medicine

authors： Sharif B,Dharmakumar R,Arsanjani R,Thomson L,Bairey Merz CN,Berman DS,Li D

更新日期：2014-12-01 00:00:00

abstract：PURPOSE:To significantly reduce the background phase effects, especially at the air-tissue interface, and to enhance the desirable local structures of veins in susceptibility-weighted imaging. METHODS:In the proposed reconstruction method called Magnitude of Complex Filtering, a complex-valued magnetic resonance image...

journal_title：Magnetic resonance in medicine

authors： Lee Y,Han Y,Park H

更新日期：2014-03-01 00:00:00

abstract：PURPOSE:Recent literature shows that diffusion tensor properties can be estimated more accurately with diffusion kurtosis imaging (DKI) than with diffusion tensor imaging (DTI). Furthermore, the additional non-Gaussian diffusion features from DKI can be sensitive markers for tissue characterization. Despite these benef...

journal_title：Magnetic resonance in medicine

authors： Tax CM,Otte WM,Viergever MA,Dijkhuizen RM,Leemans A

更新日期：2015-02-01 00:00:00

abstract：:Cardiac metabolism was studied with 31P NMR in 7 dogs and 4 cats to determine whether animals adapted for different life-styles (stalk and sprint vs endurance running) respond to increased work loads (heart rate X blood pressure product) with different high-energy phosphate kinetics. Hearts were exposed via a left lat...

journal_title：Magnetic resonance in medicine

authors： Ligeti L,Osbakken MD,Clark BJ,Schnall M,Bolinger L,Subramanian H,Leigh JS,Chance B

更新日期：1987-02-01 00:00:00

abstract：:Radiofrequency induced pacemaker lead tip heating is one of the main reasons magnetic resonance imaging (MRI) is contraindicated for patients with pacemakers. The objective of this work was to evaluate the dependence of pacemaker lead tip heating during MRI scanning on the electrical conductivity of the medium surroun...

journal_title：Magnetic resonance in medicine

authors： Langman DA,Goldberg IB,Judy J,Paul Finn J,Ennis DB

更新日期：2012-08-01 00:00:00

abstract：:High-resolution magic-angle spinning has become a valuable tool to study biologic samples; however, there are only a few high-resolution magic-angle spinning methodologies that have been explored specifically to deal with small semisolid biomaterials such as tissues. Here, we report a novel high-resolution (1)H NMR sp...

journal_title：Magnetic resonance in medicine

authors： Wong A,Aguiar PM,Sakellariou D

更新日期：2010-02-01 00:00:00

abstract：:TOMROP is a multiple readout single inversion-recovery sequence which may potentially allow the measurement of multi-exponential T1 recoveries in vivo by NMR imaging. It is shown that several important modifications must be made to this sequence to permit T1 to be measured accurately and reliably. With these modificat...

journal_title：Magnetic resonance in medicine

authors： Gowland PA,Leach MO

更新日期：1992-07-01 00:00:00

abstract：:The harmonic phase (HARP) method provides automatic and rapid analysis of tagged magnetic resonance (MR) images for quantification and visualization of myocardial strain. In this article, the development and implementation of a pulse sequence that acquires HARP images in real time are described. In this pulse sequence...

journal_title：Magnetic resonance in medicine

authors： Sampath S,Derbyshire JA,Atalar E,Osman NF,Prince JL

更新日期：2003-07-01 00:00:00

abstract：:Since its inception, functional magnetic resonance imaging (fMRI) has seen rapid progress in the application to neuroscience. Common gradient-recalled acquisition methods are susceptible to static field inhomogeneities, resulting in signal loss at the medial temporal area important for memory function or at the basal ...

journal_title：Magnetic resonance in medicine

authors： Song AW,Mao H,Muthupillai R,Haist F,Dixon WT

更新日期：1999-10-01 00:00:00

abstract：PURPOSE:In this work, 22 configurations for remote radiofrequency (RF) coil arrays consisting of different transmit element designs for 7 Tesla (T) ultrahigh-field MRI are compared by numerical simulations. METHODS:Investigated transmit RF element types are rectangular loops, micro striplines, micro striplines with me...

journal_title：Magnetic resonance in medicine

authors： Rietsch SHG,Orzada S,Bitz AK,Gratz M,Ladd ME,Quick HH

更新日期：2018-02-01 00:00:00

abstract：PURPOSE:Conventional fat/water separation techniques require that patients hold breath during abdominal acquisitions, which often fails and limits the achievable spatial resolution and anatomic coverage. This work presents a novel approach for free-breathing volumetric fat/water separation. METHODS:Multiecho data are ...

journal_title：Magnetic resonance in medicine

authors： Benkert T,Feng L,Sodickson DK,Chandarana H,Block KT

更新日期：2017-08-01 00:00:00

abstract：PURPOSE:Fourier decomposition (FD) is a noninvasive method for assessing ventilation and perfusion-related information in the lungs. However, the technique has a low signal-to-noise ratio (SNR) in the lung parenchyma. We present an approach to increase the SNR in both morphological and functional images. METHODS:The d...

journal_title：Magnetic resonance in medicine

authors： Corteville DM,Kjïrstad Å,Henzler T,Zöllner FG,Schad LR

更新日期：2015-05-01 00:00:00

abstract：:A stimulated echo sequence was used to obtain 19F NMR spectra from within a 4-ml voxel in a cat brain. The time dependence of the 19F NMR signal from an inert gas (CHF3) was used to calculate the blood flow in the voxel. The position of the voxel was selected using a 1H MR image. ...

journal_title：Magnetic resonance in medicine

authors： van Zijl PC,Ligeti L,Sinnwell T,Alger JR,Chesnick AS,Moonen CT,McLaughlin AC

更新日期：1990-12-01 00:00:00

abstract：:This paper presents an improved data reconstruction method for generalized autocalibrating partially parallel acquisitions (GRAPPA) using multicolumn multiline interpolation (MCMLI). Both nearest acquired line (ky) neighboring points and column (kx) neighboring points from all components of an array coil were used to ...

journal_title：Magnetic resonance in medicine

authors： Wang Z,Wang J,Detre JA

更新日期：2005-09-01 00:00:00

abstract：:Double wave vector diffusion weighting uses gradients along two different directions between excitation and acquisition. It has been shown theoretically that for restricted diffusion the signal amplitude in such an experiment can depend on the angle between the two gradient vectors. The highest amplitude is obtained w...

journal_title：Magnetic resonance in medicine

authors： Koch MA,Finsterbusch J

更新日期：2008-07-01 00:00:00

abstract：PURPOSE:An increasing number of studies show that magnetic susceptibility in white matter fibers is anisotropic and may be described by a tensor. However, the limited head rotation possible for in vivo human studies leads to an ill-conditioned inverse problem in susceptibility tensor imaging (STI). Here we suggest the ...

journal_title：Magnetic resonance in medicine

authors： Li X,van Zijl PC

更新日期：2014-09-01 00:00:00

abstract：:Applications of fMRI in functional brain imaging are mainly confined to single subject designs, prohibiting the assessment of subject or group by condition interactions (i.e., differential activations) or areas of conjoint activation. In this paper a framework for fMRI group designs, using statistical parametric mappi...

journal_title：Magnetic resonance in medicine

authors： Büchel C,Turner R,Friston K

更新日期：1997-11-01 00:00:00

abstract：PURPOSE:The optic nerve (ON) represents the sole pathway between the eyes and brain; consequently, diseases of the ON can have dramatic effects on vision. However, quantitative magnetization transfer (qMT) applications in the ON have been limited to ex vivo studies, in part because of the fatty connective tissue that s...

journal_title：Magnetic resonance in medicine

authors： Smith AK,Dortch RD,Dethrage LM,Lyttle BD,Kang H,Welch EB,Smith SA

更新日期：2017-02-01 00:00:00

abstract：:Noise in the composite magnitude signal from multiple-coil systems is usually assumed to follow a noncentral χ distribution when sum of squares is used to combine images sensed at different coils. However, this is true only if the variance of noise is the same for all coils, and no correlation exists between them. We ...

journal_title：Magnetic resonance in medicine

authors： Aja-Fernández S,Tristán-Vega A

更新日期：2012-02-01 00:00:00

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

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

abstract：PURPOSE:To evaluate proton density fat fraction (PDFF) and R2* as markers of bone marrow composition and structure in inflamed bone in patients with spondyloarthritis. METHODS:Phantoms containing fat, water, and trabecular bone were constructed with proton density fat fraction (PDFF) and bone mineral density (BMD) val...

journal_title：Magnetic resonance in medicine

authors： Bray TJP,Bainbridge A,Punwani S,Ioannou Y,Hall-Craggs MA

更新日期：2018-02-01 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：:Hyperpolarized (HP) 129Xe can be dissolved in biologically compatible lipid emulsions while maintaining sufficient polarization for in vivo vascular imaging. For xenon in Intralipid 30%, in vitro spectroscopy at 2 T yielded a chemical shift of 197 +/- 1 ppm with reference to xenon gas, a spin-lattice relaxation time T...

journal_title：Magnetic resonance in medicine

authors： Möller HE,Chawla MS,Chen XJ,Driehuys B,Hedlund LW,Wheeler CT,Johnson GA

更新日期：1999-05-01 00:00:00

abstract：PURPOSE:To evaluate the role of true diffusion and flow-related pseudodiffusion in cerebral blood flow (CBF) quantification using arterial spin labeling (ASL) with single-shot or segmented 3D gradient and spin echo (GRASE) readouts. THEORY:The extended phase graph (EPG) algorithm, originally designed to model the effe...

journal_title：Magnetic resonance in medicine

authors： He X,Wengler K,Schweitzer ME

更新日期：2018-08-01 00:00:00

abstract：:Although promising for visualizing the structure of ordered tissues, MR diffusion tensor imaging (DTI) has been hampered by long acquisition time and low spatial resolution associated with its inherently low signal-to-noise ratio (SNR). Moreover, the uncertainty in the DTI measurements has a direct impact on the accur...

journal_title：Magnetic resonance in medicine

authors： Chen B,Hsu EW

更新日期：2005-08-01 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