Time-dependent effects of hormone-deprivation therapy on prostate metabolism as detected by combined magnetic resonance imaging and 3D magnetic resonance spectroscopic imaging.

abstract：PURPOSE:The aim of this study was to develop a technique for rapid collection of chemical exchange saturation transfer images with the saturation varied to modulate signal loss transfer and enhance contrast. METHODS:Multi-echo Length and Offset VARied Saturation (MeLOVARS) divides the saturation pulse of length Tsat i...

journal_title：Magnetic resonance in medicine

authors： Song X,Xu J,Xia S,Yadav NN,Lal B,Laterra J,Bulte JW,van Zijl PC,McMahon MT

更新日期：2015-02-01 00:00:00

abstract：:Free induction decay signals are analyzed by fitting a model function directly in the time domain. No starting values are needed for linear model parameters, and omission of corrupted data points poses no problems. A significant gain of accuracy is achieved by imposing prior knowledge about the model parameters. ...

journal_title：Magnetic resonance in medicine

authors： van der Veen JW,de Beer R,Luyten PR,van Ormondt D

更新日期：1988-01-01 00:00:00

abstract：:In MRI, imaging using receiving coil arrays with a large number of elements is an area of growing interest. With increasing channel numbers for parallel acquisition, longer reconstruction times have become a significant concern. Channel reduction techniques have been proposed to reduce the processing time of channel-b...

journal_title：Magnetic resonance in medicine

authors： Huang F,Lin W,Duensing GR,Reykowski A

更新日期：2012-03-01 00:00:00

abstract：:Volume-localized proton NMR spectroscopy was used to estimate bone marrow cellularity in the posterior iliac crests of patients undergoing treatment with hematopoietic growth factors for a variety of hematologic and neoplastic disorders. Twelve patients were accrued, six of whom were studied more than once, yielding a...

journal_title：Magnetic resonance in medicine

authors： Ballon D,Jakubowski A,Gabrilove J,Graham MC,Zakowski M,Sheridan C,Koutcher JA

更新日期：1991-05-01 00:00:00

abstract：:We propose a new magnetic resonance imaging (MRI) technique that is sensitive to myocardial tissue perfusion that obviates the use of an extrinsic contrast agent. Significant advantages of such a technique are that it avoids accumulation of contrast agent when repeated studies are performed on the same subject and tha...

journal_title：Magnetic resonance in medicine

authors： Prasad PV,Burstein D,Edelman RR

更新日期：1993-08-01 00:00:00

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

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

abstract：PURPOSE:To demonstrate the feasibility of mapping gas exchange with single breath-hold hyperpolarized (HP) 129 Xe in humans, acquiring parametric maps of lung physiology. The potential benefit of acceleration using parallel imaging for this application is also explored. METHODS:Six healthy volunteers were scanned with...

journal_title：Magnetic resonance in medicine

authors： Zanette B,Santyr G

更新日期：2019-09-01 00:00:00

abstract：:Focused ultrasound heating of ex vivo bovine kidney and liver was monitored using magnetic resonance imaging (MRI) to investigate the quantitative relationship between time-dependent temperature elevations and altered contrast in MR images due to thermal coagulation. Proton resonance frequency shift MR thermometry was...

journal_title：Magnetic resonance in medicine

authors： Graham SJ,Chen L,Leitch M,Peters RD,Bronskill MJ,Foster FS,Henkelman RM,Plewes DB

更新日期：1999-02-01 00:00:00

abstract：PURPOSE:Anisotropic transverse R2 (1/T2 ) relaxation of water proton is sensitive to cartilage degenerative changes. The purpose is to develop an efficient method to extract this relaxation metric in clinical studies. METHODS:Anisotropic R2 can be measured inefficiently by standard R2 mapping after removing an isotrop...

journal_title：Magnetic resonance in medicine

authors： Pang Y,Palmieri-Smith RM,Malyarenko DI,Swanson SD,Chenevert TL

更新日期：2019-06-01 00:00:00

abstract：:The recently developed technique of gradient, high-resolution magic-angle spinning NMR (g-hr-MAS-NMR) spectroscopy was applied to the study of ex vivo human lipoma and liposarcoma tissue. Compared with conventional 1H-NMR, the g-hr-MAS method yielded a large improvement in spectral resolution and permitted the detecti...

journal_title：Magnetic resonance in medicine

authors： Millis KK,Maas WE,Cory DG,Singer S

更新日期：1997-09-01 00:00:00

abstract：:The complexity of biologic tissues, with multiple compartments each with its own diffusion and relaxation properties, requires complex formalisms to model water signal in most magnetic resonance imaging or magnetic resonance spectroscopy experiments. In this article, we describe a magnetic susceptibility-induced shift...

journal_title：Magnetic resonance in medicine

authors： Galons JP,Lope-Piedrafita S,Divijak JL,Corum C,Gillies RJ,Trouard TP

更新日期：2005-07-01 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：:The rotationally invariant trace/3 apparent diffusion coefficients (ADC) of N-acetyl aspartate (NAA), creatine and phosphocreatine (tCr), and choline (Cho) were determined using a diffusion-weighted stimulated echo acquisition mode sequence at 3 T in three separate human brain regions, namely the subcortical white mat...

journal_title：Magnetic resonance in medicine

authors： Ellegood J,Hanstock CC,Beaulieu C

更新日期：2005-05-01 00:00:00

abstract：:The eigenimage filter was used to evaluate the results of a MRI study of cerebral ischemia in a rat model. This linear filter segments a desired feature in an image sequence from other features which may interfere with its observation. The animals were imaged temporally, after occlusion of the middle cerebral artery, ...

journal_title：Magnetic resonance in medicine

authors： Peck DJ,Spickler EM,Knight RA,Hearshen DO,Windham JP

更新日期：1992-08-01 00:00:00

abstract：:A gradient coil design algorithm capable of controlling the position of the homogeneous region of interest (ROI) with respect to the current-carrying wires is required for many advanced imaging and spectroscopy applications. A modified minimum inductance target field method that allows the placement of a set of constr...

journal_title：Magnetic resonance in medicine

authors： Chronik BA,Rutt BK

更新日期：1998-02-01 00:00:00

abstract：:Phased-array coils distribute the high signal-to-noise ratio (SNR) performance of their small component surface coils over the larger area covered by the entire array. The inhomogeneous sensitivity profiles of the component surface coils result in images with very high signal near the phased-array and decreased signal...

journal_title：Magnetic resonance in medicine

authors： Murakami JW,Hayes CE,Weinberger E

更新日期：1996-04-01 00:00:00

abstract：:Human intervertebral discs were investigated by 1H NMR in vitro. The measured parameters of samples differently located in discs give the "maps" of discs. The spin-lattice relaxation-time maps show similar structure to dry matter and bound water maps, which might mean the future possibility to detect certain disc proc...

journal_title：Magnetic resonance in medicine

authors： Furó I,Bobest M,Pócsik I,Tompa K

更新日期：1986-02-01 00:00:00

abstract：:The time evolution of water diffusion, perfusion, T1, and T2 is investigated at high magnetic field (8.5 T) following permanent middle cerebral artery occlusion in the rat. Cerebral blood flow maps were obtained using arterial spin tagging. Although the quantitative perfusion measurements in ischemic tissue still pose...

journal_title：Magnetic resonance in medicine

authors： Calamante F,Lythgoe MF,Pell GS,Thomas DL,King MD,Busza AL,Sotak CH,Williams SR,Ordidge RJ,Gadian DG

更新日期：1999-03-01 00:00:00

abstract：PURPOSE:To investigate for the first time the feasibility of aortic four-dimensional (4D) flow at 7T, both contrast enhanced (CE) and non-CE. To quantify the signal-to-noise ratio (SNR) in aortic 4D flow as a function of field strength and CE with gadobenate dimeglumine (MultiHance). METHODS:Six healthy male volunteer...

journal_title：Magnetic resonance in medicine

authors： Hess AT,Bissell MM,Ntusi NA,Lewis AJ,Tunnicliffe EM,Greiser A,Stalder AF,Francis JM,Myerson SG,Neubauer S,Robson MD

更新日期：2015-05-01 00:00:00

abstract：:A current limitation of many myocardial tag acquisitions employing SPAMM encoding is the relatively rapid loss of tag contrast over the cardiac cycle. Acquisition schemes that apply line tags produce prolonged tag contrast compared with directly excited grid tags. However, a grid-tag series can be generated by combini...

journal_title：Magnetic resonance in medicine

authors： Doyle M,Walsh EG,Foster RE,Pohost GM

更新日期：1997-05-01 00:00:00

abstract：:In some dynamic applications of MRI, only a part of the field-of-view (FOV) actually undergoes dynamic changes. A class of methods, called reduced-FOV (rFOV) methods, convert the knowledge that some part of the FOV is static or not very dynamic into an increase in temporal resolution for the dynamic part, or into a re...

journal_title：Magnetic resonance in medicine

authors： Madore B,Fredrickson JO,Alley MT,Pelc NJ

更新日期：2000-04-01 00:00:00

abstract：:Multiple receivers can be utilized to enhance the spatiotemporal resolution of MRI by employing the parallel imaging technique. Previously, we have reported the L-curve Tikhonov regularization technique to mitigate noise amplification resulting from the geometrical correlations between channels in a coil array. Nevert...

journal_title：Magnetic resonance in medicine

authors： Lin FH,Wang FN,Ahlfors SP,Hämäläinen MS,Belliveau JW

更新日期：2007-10-01 00:00:00

abstract：:The shells trajectory is a 3D data acquisition method with improved efficiency compared to Cartesian sampling. It is a true center-out trajectory that does not repeatedly resample the center of k-space, and also offers advantages for motion correction. This work demonstrates that k-space undersampling can be combined ...

journal_title：Magnetic resonance in medicine

authors： Shu Y,Riederer SJ,Bernstein MA

更新日期：2006-09-01 00:00:00

abstract：:AFI (actual flip angle imaging) represents an interesting approach to map the B(1) transmit fields by measuring the spatial variations of the effective flip angle. However, the accuracy of the technique relies on the adequate spoiling of transverse magnetization. In the present work configuration theory was employed t...

journal_title：Magnetic resonance in medicine

authors： Nehrke K

更新日期：2009-01-01 00:00:00

abstract：PURPOSE:To test the feasibility of using the SPICE (SPectroscopic Imaging by exploiting spatiospectral CorrElation) technique, which uses the partial separability of spectroscopic data, for high resolution hyperpolarized (HP) 13 C spectroscopic imaging. METHODS:Numerical simulations were performed to investigate the i...

journal_title：Magnetic resonance in medicine

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

更新日期：2018-08-01 00:00:00

abstract：:Magnetic resonance imaging measurements of the apparent rate of water diffusion in tumors are sensitive to variations in tissue cellularity, which have been shown useful for characterizing tumors and their responses to treatments. However, because of technical limitations on most MRI systems, conventional pulse gradie...

journal_title：Magnetic resonance in medicine

authors： Xu J,Does MD,Gore JC

更新日期：2009-04-01 00:00:00

abstract：:Alternate methods to quantify mitochondrial activity or function have been extensively used for studying insulin resistance and type 2 diabetes mellitus, namely saturation transfer and phosphocreatine (PCr) recovery. As these methods are in fact determining different parameters, this study aimed to compare saturation ...

journal_title：Magnetic resonance in medicine

authors： Schmid AI,Schrauwen-Hinderling VB,Andreas M,Wolzt M,Moser E,Roden M

更新日期：2012-04-01 00:00:00

abstract：PURPOSE:To demonstrate how triple diffusion encoding (TDE) MRI can be applied to separately estimate the intra-axonal and extra-axonal diffusion tensors in white matter (WM). METHODS:Using a TDE pulse sequence with an axially symmetric b-matrix, diffusion MRI data were acquired at 3T for 3 healthy adults with an axial...

journal_title：Magnetic resonance in medicine

authors： Ramanna S,Moss HG,McKinnon ET,Yacoub E,Helpern JA,Jensen JH

更新日期：2020-06-01 00:00:00

abstract：:Magnetization transfer effects represent a major source of contrast in multislice turbo spin echo sequences (TSE)/fast spin echo sequences. Generally, low refocusing flip angles have become common in such MRI sequences, especially to mitigate specific absorption rate problems. Since the strength of magnetization trans...

journal_title：Magnetic resonance in medicine

authors： Weigel M,Helms G,Hennig J

更新日期：2010-01-01 00:00:00

abstract：PURPOSE:Applications of dynamic shimming require high field fidelity, and characterizing the shim field dynamics is therefore necessary. Modeling the system as linear and time-invariant, the purpose of this work was to measure the impulse response function with optimal sensitivity. THEORY AND METHODS:Frequency-swept p...

journal_title：Magnetic resonance in medicine

authors： Vannesjo SJ,Dietrich BE,Pavan M,Brunner DO,Wilm BJ,Barmet C,Pruessmann KP

更新日期：2014-08-01 00:00:00