Modulation of water diffusion during gonadotropin-induced ovulation: NMR microscopy of the ovarian follicle.

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：:A novel tagging method is introduced that increases the spatial resolution of estimates of myocardial radial thickening. The separation of adjacent parallel tag planes is customized to match the expected motion of specific regions of the heart wall. In regions in which the tags increase their separation over systole (...

journal_title：Magnetic resonance in medicine

authors： McVeigh ER,Bolster BD Jr

更新日期：1998-04-01 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:Either SENSE+CG or POCS-ICE methods can be used to correct for motion-induced phase errors in navigator-free multishot diffusion imaging. SENSE+CG has the advantage of a fast convergence, however, occasionally the convergence can be unstable, thus degrading the image quality. POCS-ICE has a stable convergence a...

journal_title：Magnetic resonance in medicine

authors： Hu Z,Ma X,Truong TK,Song AW,Guo H

更新日期：2017-07-01 00:00:00

abstract：PURPOSE:We propose a new acquisition to minimize the per-excitation encoding duration and improve the imaging capability for short T2 * species. METHODS:In the proposed ramped hybrid encoding (RHE) technique, gradients are applied before the radiofrequency (RF) pulse as in pointwise encoding time reduction with radial...

journal_title：Magnetic resonance in medicine

authors： Jang H,Wiens CN,McMillan AB

更新日期：2016-09-01 00:00:00

abstract：:A technique for noninvasively quantifying the concentration of sodium ((23) Na) ions was applied to the study of ischemic stroke. (23) Na-magnetic resonance imaging techniques have shown considerable potential for measuring subtle changes in ischemic tissue, although studies to date have suffered primarily from poor s...

journal_title：Magnetic resonance in medicine

authors： Wetterling F,Gallagher L,Macrae IM,Junge S,Fagan AJ

更新日期：2012-03-01 00:00:00

abstract：:Developing a method to noninvasively monitor tissue-engineered constructs is critical for the optimization of construct design and for assessing therapeutic efficacy. For this purpose, NMR is a powerful technique that can be used to obtain both images and spectroscopic data. But the inherent sensitivity of NMR limits ...

journal_title：Magnetic resonance in medicine

authors： Volland NA,Mareci TH,Constantinidis I,Simpson NE

更新日期：2010-04-01 00:00:00

abstract：PURPOSE:Diffusion-weighted imaging (DWI) and 18 F-fluorodeoxyglucose-positron emission tomography (18 F-FDG-PET) independently correlate with malignancy in breast cancer, but the relationship between their structural and metabolic metrics is not completely understood. This study spatially correlates diffusion, perfusio...

journal_title：Magnetic resonance in medicine

authors： Ostenson J,Pujara AC,Mikheev A,Moy L,Kim SG,Melsaether AN,Jhaveri K,Adams S,Faul D,Glielmi C,Geppert C,Feiweier T,Jackson K,Cho GY,Boada FE,Sigmund EE

更新日期：2017-09-01 00:00:00

abstract：PURPOSE:To model and correct the dephasing effects in the gradient-echo signal for arbitrary RF excitation pulses with large flip angles in the presence of macroscopic field variations. METHODS:The dephasing of the spoiled 2D gradient-echo signal was modeled using a numerical solution of the Bloch equations to calcula...

journal_title：Magnetic resonance in medicine

authors： Soellradl M,Lesch A,Strasser J,Pirpamer L,Stollberger R,Ropele S,Langkammer C

更新日期：2020-08-01 00:00:00

abstract：:Kinetic analysis with mathematical models has become increasingly important to quantify physiological parameters in computed tomography (CT), positron emission tomography (PET), and dynamic contrast-enhanced MRI (DCE-MRI). The modified Kety/Tofts model and the graphical (Patlak) model have been widely applied to DCE-M...

journal_title：Magnetic resonance in medicine

authors： Chen H,Li F,Zhao X,Yuan C,Rutt B,Kerwin WS

更新日期：2011-09-01 00:00:00

abstract：PURPOSE:To investigate the use of shielded-coaxial-cable (SCC) coils as elements for multi-channel receive-only and transceive arrays for 7T human MRI and to compare their performance with equivalently sized conventional loop coils. METHODS:The SCC coil element consists of a coaxial loop with interrupted central condu...

journal_title：Magnetic resonance in medicine

authors： Ruytenberg T,Webb A,Zivkovic I

更新日期：2020-03-01 00:00:00

abstract：PURPOSE:Treatments using high-intensity focused ultrasound (HIFU) in the abdominal region remain challenging as a result of respiratory organ motion. A novel method is described here to achieve 3D motion-compensated ultrasound (US) MR-guided HIFU therapy using simultaneous ultrasound and MRI. METHODS:A truly hybrid US...

journal_title：Magnetic resonance in medicine

authors： Celicanin Z,Manasseh G,Petrusca L,Scheffler K,Auboiroux V,Crowe LA,Hyacinthe JN,Natsuaki Y,Santini F,Becker CD,Terraz S,Bieri O,Salomir R

更新日期：2018-05-01 00:00:00

abstract：:MRI using hyperpolarized (13) C-labeled pyruvate is a promising tool to biochemically profile tumors and monitor their response to therapy. This technique requires injection of pyruvate into tumor-bearing animals. Pyruvate is an endogenous entity but the influence of exogenously injected bolus doses of pyruvate on tum...

journal_title：Magnetic resonance in medicine

authors： Saito K,Matsumoto S,Devasahayam N,Subramanian S,Munasinghe JP,Morris HD,Lizak MJ,Ardenkjaer-Larsen JH,Mitchell JB,Krishna MC

更新日期：2012-03-01 00:00:00

abstract：:Recovery of the cerebral cortex after 10 min of cardiac arrest was studied in rat using noninvasive MRI techniques. The apparent diffusion coefficient (ADC) of brain water was imaged to document reversal of the metabolic impairment. Perfusion-weighted imaging and blood oxygen level dependent (BOLD) imaging were perfor...

journal_title：Magnetic resonance in medicine

authors： Schmitz B,Bock C,Hoehn-Berlage M,Kerskens CM,Böttiger BW,Hossmann KA

更新日期：1998-05-01 00:00:00

abstract：PURPOSE:To improve imaging performance for body MRI with a local transmit array at 10.5T, the geometry of a dipole antenna was optimized to achieve lower peak specific absorption rate (SAR) levels and a more uniform transmit profile. METHODS:Electromagnetic simulations on a phantom were used to evaluate the SAR and ...

journal_title：Magnetic resonance in medicine

authors： Steensma B,van de Moortele PF,Ertürk A,Grant A,Adriany G,Luijten P,Klomp D,van den Berg N,Metzger G,Raaijmakers A

更新日期：2020-11-01 00:00:00

abstract：:In vivo effective relaxation rates in normal rat liver were evaluated for four dextran coated iron oxide agents: monocrystalline iron oxide nanocolloid (MION) with a mean particle diameter of 3.9 nm, a polycrystalline agent (PION) with a larger mean diameter of 12 nm, and these two agents labeled with the asialofetuin...

journal_title：Magnetic resonance in medicine

authors： Mandeville JB,Moore J,Chesler DA,Garrido L,Weissleder R,Weisskoff RM

更新日期：1997-06-01 00:00:00

abstract：:Cerebral blood volume changes with arterial carbon dioxide were monitored by proton T1-weighted MR images following administration of the intravascular contrast agent Gd-DTPA labeled with human serum albumin. Without MR contrast, no significant image intensity changes were observed with PaCO2. Following contrast, regi...

journal_title：Magnetic resonance in medicine

authors： Moseley ME,Chew WM,White DL,Kucharczyk J,Litt L,Derugin N,Dupon J,Brasch RC,Norman D

更新日期：1992-01-01 00:00:00

abstract：PURPOSE:A direct method of imaging neural activity was simulated to determine typical signal sizes. METHODS:An active bidomain finite-element model was used to estimate approximate perturbations in MR phase data as a result of neural tissue activity, and when an external MR electrical impedance tomography imaging curr...

journal_title：Magnetic resonance in medicine

authors： Sadleir RJ,Fu F,Chauhan M

更新日期：2019-01-01 00:00:00

abstract：:The reconstruction of non-Cartesian k-space trajectories often requires the estimation of nonuniform sampling density. Particularly for 3D, this calculation can be computationally expensive. The method proposed in this work combines an iterative algorithm previously proposed by Pipe and Menon (Magn Reson Med 1999;41:1...

journal_title：Magnetic resonance in medicine

authors： Zwart NR,Johnson KO,Pipe JG

更新日期：2012-03-01 00:00:00

abstract：:In vivo 1H MRS can be used to detect and quantify the lactate resonance at 1.3 ppm provided that overlapping lipid resonances are eliminated. A homonuclear spectral editing method was developed to acquire uncontaminated 1H spectra of lactate with adiabatic pulses. An advantage of the adiabatic pulse sequence is the ab...

journal_title：Magnetic resonance in medicine

authors： Schupp DG,Merkle H,Ellermann JM,Ke Y,Garwood M

更新日期：1993-07-01 00:00:00

abstract：:To increase image acquisition efficiency, we develop alternative gradient encoding strategies designed to provide spatial encoding complementary to the spatial encoding provided by the multiple receiver coil elements in parallel image acquisitions. Intuitively, complementary encoding is achieved when the magnetic fiel...

journal_title：Magnetic resonance in medicine

authors： Tam LK,Stockmann JP,Galiana G,Constable RT

更新日期：2012-10-01 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:To develop and evaluate a neural network-based method for Gibbs artifact and noise removal. METHODS:A convolutional neural network (CNN) was designed for artifact removal in diffusion-weighted imaging data. Two implementations were considered: one for magnitude images and one for complex images. Both models we...

journal_title：Magnetic resonance in medicine

authors： Muckley MJ,Ades-Aron B,Papaioannou A,Lemberskiy G,Solomon E,Lui YW,Sodickson DK,Fieremans E,Novikov DS,Knoll F

更新日期：2021-01-01 00:00:00

abstract：:Tumor pH is physiologically important since it influences a number of processes relevant to tumorigenesis and therapy. Hence, knowledge of localized pH within tumors would contribute to understanding these processes. The destructiveness, poor spatial resolution, and poor signal-to-noise ratio (SNR) of current technolo...

journal_title：Magnetic resonance in medicine

authors： van Sluis R,Bhujwalla ZM,Raghunand N,Ballesteros P,Alvarez J,Cerdán S,Galons JP,Gillies RJ

更新日期：1999-04-01 00:00:00

abstract：:31P NMR of superfused resting cartilage demonstrated the presence of phosphocreatine in chondrocytes. Changes in pH and in the NTP level were followed during carbon source starvation. From 31P spectra of perchloric acid extracts, phosphoethanolamine, phosphocholine, and the corresponding glycerol diesters were identif...

journal_title：Magnetic resonance in medicine

authors： Kvam BJ,Pollesello P,Vittur F,Paoletti S

更新日期：1992-06-01 00:00:00

abstract：:Spin-echo images of 10 myocardial infarcts in nine mini-pigs were obtained at 30 h, 3 days, and approximately 10 days postinfarction. Infarcts were not detected at all at 30 h in five out of five cases examined. At 3 days postembolization (six cases) one infarct was certainly detected, whilst at 10 days (nine cases) a...

journal_title：Magnetic resonance in medicine

authors： Checkley D,Loveday BE,Waterton JC,Zhu XP,Isherwood I

更新日期：1987-09-01 00:00:00

abstract：:A simple and reliable method for quantifying the fluid content and characterizing the tissue T2 relaxation properties of animal extremities has been devised. This one-dimensional magnetic resonance imaging experiment, applied to the adjuvant arthritis model in rats, provides a useful, noninvasive monitor of the course...

journal_title：Magnetic resonance in medicine

authors： Borah B,Szeverenyi NM

更新日期：1990-08-01 00:00:00

abstract：:In this study, a spin- and gradient-echo echo-planar imaging (SAGE EPI) MRI pulse sequence is presented that allows simultaneous measurements of gradient-echo and spin-echo dynamic susceptibility-contrast perfusion-weighted imaging data. Following signal excitation, five readout trains were acquired using spin- and gr...

journal_title：Magnetic resonance in medicine

authors： Schmiedeskamp H,Straka M,Newbould RD,Zaharchuk G,Andre JB,Olivot JM,Moseley ME,Albers GW,Bammer R

更新日期：2012-07-01 00:00:00

abstract：:Chemical shifts were extracted from in vivo 3-dimensional 31P NMR CSI data and pH images were constructed. The images could spatially resolve tissue pH ranging from 5.8 to 7.2 (with uncertainty of 0.11-0.17 pH unit) in an ischemia-reperfusion model of diabetic rat calf muscles. ...

journal_title：Magnetic resonance in medicine

authors： Morikawa S,Inubushi T,Kito K,Kido C

更新日期：1993-02-01 00:00:00

abstract：:Head motion is a fundamental problem in functional magnetic resonance imaging and is often a limiting factor in its clinical implementation. This work presents a rigid-body motion correction strategy for echo-planar imaging sequences that uses micro radiofrequency coil "active markers" for real-time, slice-by-slice pr...

journal_title：Magnetic resonance in medicine

authors： Ooi MB,Krueger S,Muraskin J,Thomas WJ,Brown TR

更新日期：2011-07-01 00:00:00