Localized two-dimensional shift correlated spectroscopy in humans at 2 Tesla.

abstract：PURPOSE:To develop a method that fits a multipool model to z-spectra acquired from non-steady state sequences, taking into account the effects of variations in T1 or B1 amplitude and the results estimating the parameters for a four-pool model to describe the z-spectrum from the healthy brain. METHODS:We compared measu...

journal_title：Magnetic resonance in medicine

authors： Geades N,Hunt BAE,Shah SM,Peters A,Mougin OE,Gowland PA

更新日期：2017-08-01 00:00:00

abstract：:For perfusion-based functional magnetic resonance imaging, the previously introduced flow-sensitive alternating inversion recovery (FAIR) technique is combined with single-shot RARE (rapid acquisition with relaxation enhancement) and GRASE (gradient and spin echo) imaging sequences. The advantages of these sequences c...

journal_title：Magnetic resonance in medicine

authors： Crelier GR,Hoge RD,Munger P,Pike GB

更新日期：1999-01-01 00:00:00

abstract：:The vascular space occupancy (VASO) method was recently proposed as a functional MRI (fMRI) method that is capable of detecting activation-related changes in blood volume (CBV), without the need for a blood-pool contrast agent. In the present work we introduce a new whole-brain VASO technique that is based on a parall...

journal_title：Magnetic resonance in medicine

authors： Poser BA,Norris DG

更新日期：2009-07-01 00:00:00

abstract：:The image intensity in magnetic resonance magnitude images in the presence of noise is shown to be governed by a Rician distribution. Low signal intensities (SNR < 2) are therefore biased due to the noise. It is shown how the underlying noise can be estimated from the images and a simple correction scheme is provided ...

journal_title：Magnetic resonance in medicine

authors： Gudbjartsson H,Patz S

更新日期：1995-12-01 00:00:00

abstract：:A novel method based on selective detection of rapidly changing DeltaB(0) magnetic fields and suppression of slowly changing DeltaB(0) fields is presented. The ultimate goal of this work is to present a method that may allow detection of transient and subtle changes in B(0) in cortical tissue associated with electrica...

journal_title：Magnetic resonance in medicine

authors： Bodurka J,Bandettini PA

更新日期：2002-06-01 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：:A lactate editing sequence based on the use of spin-locking pulses with surface coils is described. The sequence retains more than 90% of the available lactate magnetization and suppresses at least 95% of the lipid signal in a single scan and ca. 99.5% after a simple two step cycle. The technique allows simultaneous o...

journal_title：Magnetic resonance in medicine

authors： Bourgeois D,Kozlowski P

更新日期：1993-03-01 00:00:00

abstract：:An optimized multislice data acquisition scheme for phase acquisition of composite echoes (PACE) imaging is presented. This new scheme uses a repetition time equal to the mixing time and an appropriate phase cycling scheme, which allows for more efficient exploitation of all composite echoes. These modifications provi...

journal_title：Magnetic resonance in medicine

authors： Ropele S,Stollberger R,Kapeller P,Hartung HP,Fazekas F

更新日期：1999-12-01 00:00:00

abstract：:Direct measurement of neural currents by means of MRI can potentially open a high temporal resolution (10-100 ms) window applicable for monitoring dynamics of neuronal activity without loss of the high spatial resolution afforded by MRI. Previously, we have shown that the alternating balanced steady state imaging affo...

journal_title：Magnetic resonance in medicine

authors： Buračas GT,Jung Y,Lee J,Buxton RB,Wong EC,Liu TT

更新日期：2012-05-01 00:00:00

abstract：PURPOSE:We incorporate simultaneous multislice (SMS) acquisition into MR fingerprinting (MRF) to accelerate the MRF acquisition. METHODS:The t-Blipped SMS-MRF method is achieved by adding a Gz blip before each data acquisition window and balancing it with a Gz blip of opposing polarity at the end of each TR. Thus the ...

journal_title：Magnetic resonance in medicine

authors： Ye H,Ma D,Jiang Y,Cauley SF,Du Y,Wald LL,Griswold MA,Setsompop K

更新日期：2016-05-01 00:00:00

abstract：PURPOSE:To improve the specific absorption rate (SAR) compression model capability in parallel transmission (pTx) MRI systems. METHODS:A k-means clustering method is proposed to group voxels with similar SAR behaviors in the scanned object, providing a controlled upper-bounded estimation of peak local SARs. This k-mea...

journal_title：Magnetic resonance in medicine

authors： Mao X,Bari S,Love DJ,Rispoli JV

更新日期：2021-02-01 00:00:00

abstract：:Elastase-induced changes in lung morphology and function were detected in spontaneously breathing rats using conventional proton MRI at 4.7 T. A single dose of porcine pancreatic elastase (75 U/100 g body weight) or vehicle (saline) was administered intratracheally (i.t.) to male Brown Norway (BN) rats. MRI fluid sign...

journal_title：Magnetic resonance in medicine

authors： Quintana HK,Cannet C,Zurbruegg S,Blé FX,Fozard JR,Page CP,Beckmann N

更新日期：2006-12-01 00:00:00

abstract：PURPOSE:Within multiple sclerosis (MS) lesions iron is present in chronically activated microglia. Thus, iron detection with MRI might provide a biomarker for chronic inflammation within lesions. Here, we examine contributions of iron and myelin to magnetic susceptibility of lesions on quantitative susceptibility mappi...

journal_title：Magnetic resonance in medicine

authors： Wisnieff C,Ramanan S,Olesik J,Gauthier S,Wang Y,Pitt D

更新日期：2015-08-01 00:00:00

abstract：PURPOSE:To determine whether neurochemical concentrations obtained at two MRI sites using clinical 3T scanners can be pooled when a highly optimized, nonvendor short-echo, single-voxel proton MRS pulse sequence is used in conjunction with identical calibration and quantification procedures. METHODS:A modified semi-LAS...

journal_title：Magnetic resonance in medicine

authors： Deelchand DK,Adanyeguh IM,Emir UE,Nguyen TM,Valabregue R,Henry PG,Mochel F,Öz G

更新日期：2015-05-01 00:00:00

abstract：:Two-dimensional T2-selective proton imaging of human head has been performed at 10 MHz employing Carr-Purcell-Gill-Meiboom pulse trains with echo separation of 6 and 12 msec. Using the information of 36 spin echoes and applying a recovery time of 2 sec the magnetization decay has been traced. The multi-exponential T2 ...

journal_title：Magnetic resonance in medicine

authors： Gersonde K,Felsberg L,Tolxdorff T,Ratzel D,Ströbel B

更新日期：1984-12-01 00:00:00

abstract：:31P NMR spectroscopy was used to study renal allografts in rats subjected to allograft rejection, cyclosporine toxicity, ischemia, and ureteral obstruction. Parameters of relative peak areas and intracellular pH were accurately distinguished among the different causes of graft dysfunction. Ureteral obstruction was cle...

journal_title：Magnetic resonance in medicine

authors： Shapiro JI,Haug CE,Weil R 3rd,Chan L

更新日期：1987-10-01 00:00:00

abstract：:Spinal cord (SC) motion is thought to be the dominant source of error in current diffusion and spinal functional MRI (fMRI) methods. However, until now, such motion has not been well characterized in three dimensions. While previous studies have predominantly examined motion in the superior/inferior (S/I) direction, t...

journal_title：Magnetic resonance in medicine

authors： Figley CR,Stroman PW

更新日期：2007-07-01 00:00:00

abstract：PURPOSE:The goal of this study was to conduct an exposure assessment for workers moving through the stray stationary field of common MRI scanners, performed according to the recent International Commission on Non-Ionizing Radiation Protection (ICNIRP) Guidelines, which aim at avoiding annoying sensory effects. THEORY ...

journal_title：Magnetic resonance in medicine

authors： Zilberti L,Bottauscio O,Chiampi M

更新日期：2016-10-01 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：: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：:Radial MRI sequences are frequently used to obtain images with reduced sensitivity to motion. To decrease imaging time, multiple spin-echo acquisitions can be incorporated into radial sequences. In this case, different radial lines of Fourier data have different TE times and the resulting images can contain streaking ...

journal_title：Magnetic resonance in medicine

authors： Theilmann RJ,Gmitro AF,Altbach MI,Trouard TP

更新日期：2004-04-01 00:00:00

abstract：PURPOSE:Dynamic phosphorus MR spectroscopic imaging (31 P-MRSI) experiments require temporal resolution on the order of seconds to concurrently assess different muscle groups. A highly accelerated pulse sequence combining flyback echo-planar spectroscopic imaging (EPSI) and compressed sensing was developed and tested i...

journal_title：Magnetic resonance in medicine

authors： Santos-Díaz A,Harasym D,Noseworthy MD

更新日期：2019-06-01 00:00:00

abstract：:A method is described for multislice imaging by means of rf pulses which contain a multifrequency excitation spectrum. These pulses label each slice by an individual signal phase and allow the separation of the signals from all the slices by subsequent add/subtract procedures. The image sensitivity corresponds to the ...

journal_title：Magnetic resonance in medicine

authors： Müller S

更新日期：1988-03-01 00:00:00

abstract：:Manganese is a useful contrast agent for MRI of animals. Previously, it has been shown that systemic doses of MnCl(2) provide unique contrast in the rodent brain, enabling visualization of neuroarchitecture. The present work investigates the dose and temporal dependence of brain enhancement after i.v. administration o...

journal_title：Magnetic resonance in medicine

authors： Lee JH,Silva AC,Merkle H,Koretsky AP

更新日期：2005-03-01 00:00:00

abstract：:Using a 32-echo imaging pulse sequence, T2 relaxation decay curves were acquired from five white- and six gray-matter brain structures outlined in 12 normal volunteers. The water contents of white and gray matter were 0.71 (0.01) and 0.83 (0.03) g/ml, respectively. All white-matter structures had significantly higher ...

journal_title：Magnetic resonance in medicine

authors： Whittall KP,MacKay AL,Graeb DA,Nugent RA,Li DK,Paty DW

更新日期：1997-01-01 00:00:00

abstract：:Partial-volume effects (PVE) in stroke imaging could hinder proper delineation of normal, ischemic, and at-risk tissues. Cerebral-blood-flow (CBF) and apparent diffusion coefficient (ADC) were measured at high and low resolution (HR = 128 x 128, LR = 64 x 64) in focal ischemia in rats during the acute phase. The data ...

journal_title：Magnetic resonance in medicine

authors： Ren H,Shen Q,Bardutzky J,Fisher M,Duong TQ

更新日期：2004-12-01 00:00:00

abstract：:The exponential clearance rate constant, (kappa), and filtration fraction (FF) have been measured for dialysis of Gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA) (Magnevist, Berlex, Wayne, NJ) solutions by using a Look-Locker imaging technique under conditions of flow. The measured values of kappa for the Baxt...

journal_title：Magnetic resonance in medicine

authors： Niendorf ER,Santyr GE,Brazy PC,Grist TM

更新日期：1996-10-01 00:00:00

abstract：:Function and morphology of the cerebral vasculature were studied in the amyloid (Abeta) plaque-containing double-transgenic (TG) B6.PS2APP Alzheimer's disease (AD) mouse model with MRI at an age range of 10 to 17 months. Perfusion, blood volume, and average vessel geometry were assessed in the brain and compared to ag...

journal_title：Magnetic resonance in medicine

authors： Weidensteiner C,Metzger F,Bruns A,Bohrmann B,Kuennecke B,von Kienlin M

更新日期：2009-07-01 00:00:00

abstract：:Functional MR imaging (fMRI) of activation in the brain is one of the more demanding applications required of an NMR imaging instrument. Since the signal changes in activation imaging are quite small, any instrumental variations can easily compromise the fMRI contrast. The authors describe a simple method for measurin...

journal_title：Magnetic resonance in medicine

authors： Weisskoff RM

更新日期：1996-10-01 00:00:00

abstract：:The differential effects of high temperature on 9L rat gliosarcoma cells cultured in two distinctive forms, namely, anchored monolayer cells and multicellular spheroids, were investigated using 31P nuclear magnetic resonance spectroscopy. The critical temperatures resulting in irreversible changes in cellular energeti...

journal_title：Magnetic resonance in medicine

authors： Suzuki N,Kwee IL,Tamas LB,Nakada T

更新日期：1991-06-01 00:00:00