Showing papers in "Magnetic Resonance Imaging in 2001"

TL;DR: The results show that significant improvement in the circularly polarized component of the transverse magnetic field could be obtained when using multiple ports andVariable phase and fixed magnitude, or variable phase and variable magnitude excitations.

TL;DR: There was a good correlation between the global BOLD signal intensity changes during breath holding and CO(2) inhalation supporting the notion that the BHT is equivalent to CO( 2) inhalations in evaluating the hemodynamic reserve capacity with BOLD fMRI.

TL;DR: It is concluded that in clinical UFHMRI, the most important determinants of B(1) field homogeneity consist of 1) the RF Coil design, 2) the interaction between the RF coil, the excitation source and the sample, and finally 3) the geometry and electrical properties of the sample.

TL;DR: In this article, the authors used functional magnetic resonance imaging (fMRI) to detect auditory cortical activation in non-sedated neonates employing a frequency-modulated pure tone; the BOLD signal response was mapped in 5 mm-thick slices running parallel to the superior temporal gyrus.

TL;DR: The necessity of performing cardiac gating with single shot echo planar imaging with F statistics of the variance in DWI data has been explored and a minimum trigger delay may be the best choice in terms of SNR per unit of experiment time.

TL;DR: The largest BOLD signal change as a result of forepaw stimulation was found in the awake condition, however the activated areas are less specific than those in the anesthetized state leaving it more difficult to interpret.

TL;DR: The optimized T1-w 3D FLASH water excitation (THE AUTHORS) sequence allows for rapid, valid and reproducible quantification of articular cartilage volume and thickness, prerequisites for follow-up examinations and thus may contribute to a broader assessment of osteoarthritis.

TL;DR: The robust agreement between predicted and empiric data serves to validate a semiquantitative approach to the analysis of BOLD fMRI data and suggest that hematocrit significantly influences the magnitude of BPA and that such baseline factors should be accounted for when comparing BOLD data across groups of subjects, particularly in the many instances in which hematorit may vary systematically.

TL;DR: In this paper, the diagnostic value of magnetic resonance cholangiography (MRC) was assessed when evaluating biliary complications in the follow-up of liver transplant patients. But the use of ERC was restricted to patients for whom therapeutic procedures are advocated or whose MRC results are equivocal.

TL;DR: In this article, the ability of magnetic resonance (MR) imaging with ultrasmall superparamagnetic iron oxide (USPIO) particles to provide quantitative measures of inflammation in autoimmune arthritis was determined.

TL;DR: In-vivo PMRS complements imaging in better characterization of cystic intracranial mass lesions to determine the accuracy of this technique in the differential diagnosis of these lesions.

TL;DR: The permanent-magnet compact MR microscope developed using a permanent magnet made of high performance Nd-Fe-B magnetic material and a compact MRI console has great promise as a research or analytical tool.

TL;DR: MR imaging of the cervical spinal cord was carried out on volunteers during alternated rest and either motor or sensory stimulation of one hand, in order to detect image intensity changes arising concomitant to neuronal activity.

TL;DR: The results of this study indicate that 3D MRSI of brain tumors can detect abnormal metabolite levels in regions of viable cancer and grades and can differentiate cancer from necrosis and/or normal brain tissue.

TL;DR: Testing the performance of artificial neural networks for the classification of signal-time curves obtained from breast masses by dynamic MRI found that neural networks can computationally fast distinguish between malignant and benign lesions even when only a few post-contrast measurements are made.

TL;DR: The results demonstrate that post-natal brain development has a profound affect on the biexponential parameters which characterize the decay of water signal over an extended b-factor range in both gray and white matter.

TL;DR: Findings indicate that voxel gray/white matter contributions, regional variations in metabolite concentrations, and reliability limitations must be considered when interpreting 1H MR spectra of the brain.

TL;DR: MRI has proved to be an excellent means of studying CHCy and provided information about the exact cyst localization, cyst contents and presence or absence of superadded cyst infection.

TL;DR: It could be shown that the velocity induced phase shifts in phase contrast techniques are mainly encoded in the central sections of k-space which makes view sharing also suitable for velocity mapping, and the use of appropriate sampling and data acquisition schemes permits the assessment of flow or motion patterns with significantly improved temporal resolution without loss of functional information.

TL;DR: In vivo measurement of MT ratios gives quantitative and qualitative information on the collagen status and may be applied for the routine evaluation of normal and abnormal articular cartilage.

TL;DR: MR spectroscopy showed no significant N-acetyl aspartate depletion or lactate elevation prospectively, indicating the absence of significant neuronal loss and reversibility of the brain parenchymal changes.

TL;DR: In this paper, the authors performed dynamic contrast MRI to study whether trophoblastic villi could be separately demonstrated from the decidua basalis, and whether the contrast resolution between the placenta and myometrium could improve compared to T2WI.

TL;DR: The pH-sensitivity of the DPPE/PA liposome system was confirmed in an in vitro magnetic resonance imaging (MRI) phantom study and the in vitro relaxometric properties of the liposomal Gd chelate were shown to be a function of the pH in the Liposomal dispersion and the membrane composition.

TL;DR: A AIR 3.08, SPM99, AFNI98, and the pyramid method of Thevenaz, Ruttimann, and Unser (TRU) are compared, with AIR found to be the least accurate program studied.

TL;DR: Different contrast weighted images with high and comparable IQ will yield similar results in lumen and vessel wall area measurement.

TL;DR: The calculations show that already small distributions of pathologically changed brain tissue should be detectable by MRE even within the limit of relatively low shear wave excitation frequency around 0.2 kHz.

TL;DR: In this article, the authors extended the utility of NMR as a technique to probe porous media structure over length scales of approximately 100-2000 microm by using the spin 1/2 noble gas 129Xe imbibed into the system's pore space.

TL;DR: In addition to the BOLD effect there is a baseline signal change which occurs concomitant to neuronal activation in the spinal cord as a function of echo time.

TL;DR: The results demonstrate the presence of a similar neural activity-induced hemodynamic response in the inferior to middle left frontal lobe during both tasks and strongly imply that the underlying neural mechanism for Chinese (first) and English (second) language processing may be similar in native Chinese speakers.

TL;DR: A new CDI technique is presented, which extends the CDI frequency range to alternating electric currents (AC-CDI), and the effect of off-resonance spins and imperfect refocusing RF pulses on the stability of the AC- CDI sequence and the echo formation is studied.