PLANET: An ellipse fitting approach for simultaneous T1 and T2 mapping using phase-cycled balanced steady-state free precession.

abstract：:The objective of this study is to evaluate the effect of MR image resolution on trabecular bone parameters and to determine the acceptable resolution that can be accurately analyzed to assess structural parameters. Ten distal femoral condyle specimens of 1 × 1 × 1 cm(3) were scanned with a 4.7-T Bruker BioSpec MRI sca...

journal_title：Magnetic resonance in medicine

authors： Kim N,Lee JG,Song Y,Kim HJ,S Yeom J,Cho G

更新日期：2012-01-01 00:00:00

abstract：:A simple theoretical model was developed to compare the sensitivities (i.e., signal-to-noise ratios per unit imaging time) of two-dimensional (2D) multislice and 3D imaging sequences. The model shows that the sensitivities of 3D and 2D multislice MRI sequences are usually similar. Sensitivities are identical in T2-wei...

journal_title：Magnetic resonance in medicine

authors： Johnson G,Wadghiri YZ,Turnbull DH

更新日期：1999-04-01 00:00:00

abstract：PURPOSE:To develop and validate closed form mathematical expressions that predict the optimal contrast agent concentration for the maximum T1-weighted spoiled gradient echo (SGRE) signal. THEORY AND METHODS:Gadolinium and iron-based contrast agents can have significant transverse relaxivity that leads to signal dropou...

journal_title：Magnetic resonance in medicine

authors： Reeder SB,Smith MR,Hernando D

更新日期：2016-04-01 00:00:00

abstract：:A novel ultra-rapid gradient echo (URGE) NMR imaging technique is introduced, which is capable of continuous high resolution 3D scanning while neither subject to fast gradient switching nor excessive RF power deposition. Sampling free induction decays instead of creating spin echoes enables maintaining a workable stea...

journal_title：Magnetic resonance in medicine

authors： Heid O,Deimling M,Huk WJ

更新日期：1995-01-01 00:00:00

abstract：:Chemically-fixed nervous tissues are well-suited for high-resolution, time-intensive MRI acquisitions without motion artifacts, such as those required for brain atlas projects, but the aldehyde fixatives used may significantly alter tissue MRI properties. To test this hypothesis, this study characterized the impact of...

journal_title：Magnetic resonance in medicine

authors： Shepherd TM,Thelwall PE,Stanisz GJ,Blackband SJ

更新日期：2009-07-01 00:00:00

abstract：:Prepolarized MRI uses pulsed magnetic fields to produce MR images by polarizing the sample at one field strength (approximately 0.5 T) before imaging at a much lower field (approximately 50 mT). Contrast reflecting the T(1) of the sample at an intermediate field strength is achieved by polarizing the sample and then a...

journal_title：Magnetic resonance in medicine

authors： Ungersma SE,Matter NI,Hardy JW,Venook RD,Macovski A,Conolly SM,Scott GC

更新日期：2006-06-01 00:00:00

abstract：PURPOSE:To develop an MRI acquisition and reconstruction framework for volumetric cine visualization of the fetal heart and great vessels in the presence of maternal and fetal motion. METHODS:Four-dimensional (4D) depiction was achieved using a highly-accelerated multi-planar real-time balanced steady-state free prece...

journal_title：Magnetic resonance in medicine

authors： van Amerom JFP,Lloyd DFA,Deprez M,Price AN,Malik SJ,Pushparajah K,van Poppel MPM,Rutherford MA,Razavi R,Hajnal JV

更新日期：2019-09-01 00:00:00

abstract：:Endogenous glucose production (EGP), gluconeogenic and glycogenolytic fluxes by analysis of a single (2)H-NMR spectrum is demonstrated with 6-hr and 24-hr fasted rats. Animals were administered [1-(2)H, 1-(13)C]glucose, a novel tracer of glucose turnover, and (2)H(2)O. Plasma glucose enrichment from both tracers was q...

journal_title：Magnetic resonance in medicine

authors： Nunes PM,Jones JG

更新日期：2009-09-01 00:00:00

abstract：:A partial saturation method is described for obtaining rapid images of tissue 1H spin-lattice relaxation rates following administration of the paramagnetic contrast agent gadolinium-diethylenetriaminepentaacetate. The paramagnetic contribution to the relaxation rates is proportional to the concentration of contrast ag...

journal_title：Magnetic resonance in medicine

authors： Kennedy SD,Szczepaniak LS,Gibson SL,Hilf R,Foster TH,Bryant RG

更新日期：1994-03-01 00:00:00

abstract：:A novel method, called relaxo-oximetry, for rapid spatially resolved in vivo measurements of oxygen concentration using time-domain radiofrequency (RF) electron paramagnetic resonance (EPR) is described. Time-domain data from triaryl methyl (TAM)-based single-electron contrast agents were processed by systematic delet...

journal_title：Magnetic resonance in medicine

authors： Subramanian S,Yamada K,Irie A,Murugesan R,Cook JA,Devasahayam N,Van Dam GM,Mitchell JB,Krishna MC

更新日期：2002-05-01 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：:A novel method for reducing the rf power requirements of selective pulses employed for z magnetization slice inversion in localized NMR spectroscopy is presented. Following slice preparation by the use of frequency-incremented sinc pulses, the slice gradient is reduced, which narrows the frequency width of the slice. ...

journal_title：Magnetic resonance in medicine

authors： Brereton IM,Brooks WM,Marshman MF,Field J,Doddrell DM

更新日期：1987-12-01 00:00:00

abstract：PURPOSE:The aim of the study was to investigate whether incorrectly compensated eddy currents are the source of persistent X-nuclear spectroscopy and imaging artifacts, as well as methods to correct this. METHODS:Pulse-acquire spectra were collected for 1 H and X-nuclei (23 Na or 31 P) using the minimum TR permitted o...

journal_title：Magnetic resonance in medicine

authors： McLean MA,Hinks RS,Kaggie JD,Woitek R,Riemer F,Graves MJ,McIntyre DJO,Gallagher FA,Schulte RF

更新日期：2020-12-04 00:00:00

abstract：PURPOSE:The purpose of this study is to increase the robustness of MR fingerprinting (MRF) toward subject motion. METHODS:A novel reconstruction algorithm, MOtion insensitive MRF (MORF), was developed, which uses an iterative reconstruction based retrospective motion correction approach. Each iteration loops through t...

journal_title：Magnetic resonance in medicine

authors： Mehta BB,Ma D,Pierre EY,Jiang Y,Coppo S,Griswold MA

更新日期：2018-12-01 00:00:00

abstract：:The relaxation of (1)H nuclei due to their interaction with quadrupolar (14)N nuclei in gel structures is measured using fast field-cycling NMR. This phenomenon called quadrupolar dips has been reported in different (1)H-(14)N bond-rich species. In this study, we have studied quadrupolar dips in fibrin, an insoluble p...

journal_title：Magnetic resonance in medicine

authors： Broche LM,Ismail SR,Booth NA,Lurie DJ

更新日期：2012-05-01 00:00:00

abstract：PURPOSE:To develop a prospective baseline enhancement that compensates for intermingled background effects in Z-spectra to achieve sensitivity enhancement of peaks related to CEST and nuclear Overhauser effect. METHODS:An MRI sequence-specific compensation of background effects is achieved through variation of the pul...

journal_title：Magnetic resonance in medicine

authors： Lenich T,Pampel A,Mildner T,Möller HE

更新日期：2019-04-01 00:00:00

abstract：:Image selected in vivo spectroscopy (ISIS) is a volume selection method often used for in vivo (31)P MRS, since it is suitable for measurements of substances with short T(2). However, ISIS can suffer from significant signal contributions caused by T(1) smearing from regions outside the VOI. A computer model was develo...

journal_title：Magnetic resonance in medicine

authors： Ljungberg M,Starck G,Vikhoff-Baaz B,Alpsten M,Ekholm S,Forssell-Aronsson E

更新日期：2000-10-01 00:00:00

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

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

abstract：:The proton exchange rates between water and the hydroxyl protons of threonine, serine, tyrosine, the amino protons of lysine, and the guanidinium protons of arginine were measured in the pH range 0.5 to 8.5 and for the temperatures 4 degrees C, 10 degrees C, 20 degrees C, 30 degrees C, and 36 degrees C. The intrinsic ...

journal_title：Magnetic resonance in medicine

authors： Liepinsh E,Otting G

更新日期：1996-01-01 00:00:00

abstract：:Quantitative artificial neural network analysis for 1550 ex vivo 31P nuclear magnetic resonance spectra from hypothermically reperfused pig livers was assessed. These spectra show wide ranges of metabolite concentrations and have been analyzed using metabolite prior knowledge based lineshape fitting analysis which had...

journal_title：Magnetic resonance in medicine

authors： Ala-Korpela M,Changani KK,Hiltunen Y,Bell JD,Fuller BJ,Bryant DJ,Taylor-Robinson SD,Davidson BR

更新日期：1997-11-01 00:00:00

abstract：:A gradient technique to measure electron paramagnetic resonance spectra simultaneously at several different locations is described. The technique is based on the use of point probes containing paramagnetic centers. The value of the magnetic field gradient is chosen to be sufficient to separate the EPR signals from the...

journal_title：Magnetic resonance in medicine

authors： Smirnov AI,Norby SW,Clarkson RB,Walczak T,Swartz HM

更新日期：1993-08-01 00:00:00

abstract：:The ability to generate in vivo maps of lactate may have significant diagnostic utility in staging and treatment planning of a wide variety of cancers. The double selective multiple quantum filter technique (SelMQC) has been shown to be effective for nonlocalized detection of lactate with little or no interference fro...

journal_title：Magnetic resonance in medicine

authors： Pickup S,Lee SC,Mancuso A,Glickson JD

更新日期：2008-08-01 00:00:00

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

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

更新日期：2008-09-01 00:00:00

abstract：:MnCl(2) was injected intrathecally through the cisterna magna in rats, allowing infusion of divalent manganese ions (Mn(++)) into the CSF space and thence into the brain, without breaking the blood-brain barrier (BBB). Mn(++) uptake and washout dynamics in the brain were measured by serial T(1)-weighted MRI and EPI T(...

journal_title：Magnetic resonance in medicine

authors： Liu CH,D'Arceuil HE,de Crespigny AJ

更新日期：2004-05-01 00:00:00

abstract：:Since background signal from NMR probes can overwhelm the signal from a sample, the NMR analysis of plastics or machinable ceramics is a prerequisite to their use in probe implementations. The contributions from a variety of materials to proton, fluorine, and carbon NMR spectra are presented. ...

journal_title：Magnetic resonance in medicine

authors： Babcock EE,Vaughan JT,Lesan B,Nunnally RL

更新日期：1990-03-01 00:00:00

abstract：:In order to determine if an increase in myocardial oxygen consumption is accompanied by changes in high energy phosphates in normal subjects and patients with dilated cardiomyopathy, phosphorus-31 spectra were acquired under resting conditions and during dobutamine infusion. In seven normal subjects, dobutamine raised...

journal_title：Magnetic resonance in medicine

authors： Schaefer S,Schwartz GG,Steinman SK,Meyerhoff DJ,Massie BM,Weiner MW

更新日期：1992-06-01 00:00:00

abstract：PURPOSE:Assessing the functionality of muscle fibers is essential to monitor both pathological and physiological processes. Here, we present a new method for accurate, quantitative measurement of muscle contraction with magnetic resonance imaging (MRI) using an electrical muscle stimulator (EMS), hence allowing the dir...

journal_title：Magnetic resonance in medicine

authors： Deligianni X,Pansini M,Garcia M,Hirschmann A,Schmidt-Trucksäss A,Bieri O,Santini F

更新日期：2017-02-01 00:00:00

abstract：:Combined MRI and 3D spectroscopic imaging (MRI/3D-MRSI) was used to study the metabolic effects of hormone-deprivation therapy in 65 prostate cancer patients, who underwent either short, intermediate, or long-term therapy, compared to 30 untreated control patients. There was a significant time-dependent loss of the pr...

journal_title：Magnetic resonance in medicine

authors： Mueller-Lisse UG,Swanson MG,Vigneron DB,Hricak H,Bessette A,Males RG,Wood PJ,Noworolski S,Nelson SJ,Barken I,Carroll PR,Kurhanewicz J

更新日期：2001-07-01 00:00:00

abstract：:This paper describes a method for correcting the chemical-shift artifacts in 19F NMR imaging of perfluoroctylbromide emulsion (PFOB) by utilizing the two spectral peaks of PFOB which have a long T2 value in conjunction with the Dixon method. Corrected images are obtained from the magnitude of the measured images using...

journal_title：Magnetic resonance in medicine

authors： Lee HK,Nalcioglu O,Buxton RB

更新日期：1992-02-01 00:00:00

abstract：:For diffusion-weighted magnetic resonance imaging and under circumstances where patient movement can be modeled as rigid body motion, it is shown both theoretically and experimentally that translations and rotations produce phase errors which are zero- and first-order, respectively, in position. While a navigator echo...

journal_title：Magnetic resonance in medicine

authors： Anderson AW,Gore JC

更新日期：1994-09-01 00:00:00