Showing papers in "Magnetic Resonance Imaging in 1996"

TL;DR: This article examines the diagnostic ability of diffusion-weighted imaging to discriminate brain abscess from necrotic or cystic tumors and finds high signal intensity was observed in the abscess fluid, associated with low ADC.

TL;DR: Comparison with relaxivities of synthetic materials having well-defined surface areas strongly suggests that the NMR-effective internal surface area of rocks is closely connected with the hydraulic radius, and, surprisingly, is not greatly affected by the presence of clay, which dominates the pore space surface as measured by gas adsorption.

TL;DR: Methods for the noninvasive measurement of three-dimensional myocardial motion with MRI have recently been developed using presaturation tagging and velocity-encoded phase maps, making it possible to quantify the severity and extent of regional heart wall motion abnormalities both at rest and during stress.

TL;DR: The contour technique is a promising tool for use in treatment trials and its absolute lesion loads measured were very similar using the manual outlining and the contour techniques but were significantly smaller using the global threshold technique.

TL;DR: The usefulness of nanoparticles as image contrast agents is probably limited by their microdistribution within the tumor tissue, and the requirements for a contrast agent to be highly tissue specific are discussed.

TL;DR: A modified Gibbs-Thompson analysis was used to determine pore volume distributions from the distribution of thawing temperatures, finding the depression of the freezing point of liquid water confined within a pore was found to be dependent on the pore size.

TL;DR: Reproducibility in patients, who may be less cooperative, will probably be no better, and this must be taken into account in the interpretation of MRS studies in patients with brain pathology; for example, stroke, head injury, and tumours.

TL;DR: An interleaved dual spin echo-based sequence for quantitative measurement of Magnetisation Transfer Ratio (MTR) in a clinical environment that overcomes the problems of patient motion between scans faced by noninterleaved methods is demonstrated.

TL;DR: Dependence of T2 values on the orientation of specimens in the magnetic field as well as magnetization transfer experiments supported the previous suggestions about a significant role of dipolar interaction with protons of collagen in the laminar appearance of articular cartilage.

TL;DR: Reduction of NAA is consistent with the neuronal loss while reduction in Cho suggests significant changes in the membrane lipids of alcoholics.

TL;DR: Gadolinium-enhanced MR angiography is a promising technique for the evaluation of patients with carotid occlusive disease because it rapidly images the carotids arteries from the aortic arch to the skull base and eliminates some of the artifacts that degrade 2D TOF MRAngiography.

TL;DR: A procedure to quantify and improve the signal-to-noise ratio (SNR) of magnetic resonance images is developed using the correlation function of two independent acquisitions of an image, and its performance is compared to that of classical noise filters.

TL;DR: During a 5-yr observation of successfully aged elderly it was found that there was a mild increase in signal hyperintensity in the cerebral white matter and basal ganglia, as well as an increase in the frontal and ventricular CSF volumes.

TL;DR: In this paper, a tuning apparatus for detecting a target substance through the use of nuclear quadrupole resonance (NQR) or nuclear magnetic resonance was presented, which includes a series of fixed value capacitors (93) switched in the tuning circuit by controllable switches.

TL;DR: It is believed that nontriggered 2DPC is a valid technique for measuring blood flow in stationary vessels with weakly pulsatile flow, but merely provides a rough estimation for strongly pulsatileflow.

TL;DR: This study presents a study on reproducibility of gradient-echo FMRI in the human visual cortex using the different threshold strategies for correlation analysis that shows that applying adaptive correlation thresholds results in higher reproduCibility compared to a fixed (0.5) threshold.

TL;DR: A system to simulate MRI cluster plots using multicompartmental anthropomorphic software models of anatomy, and components for image contrast, signal-to-noise ratio, image nonuniformity, tissue heterogeneity, imager field strength, the partial volume effect, correlation between proton density, T1 and T2, and a variety of data preprocessing techniques is developed.

TL;DR: The results indicate that dynamic contrast-enhanced 3D MRI of the whole breast is a useful and economically feasible method for staging breast cancer, providing a comprehensive noninvasive method for total evaluation of the breast and axilla in patients considering breast conservation surgery or lumpectomy.

TL;DR: It is suggested that the difference in binding and aggregation properties of metalloporphyrins may be relevant to their relaxation efficiency in vivo, blood transport, and biodistribution.

TL;DR: It is demonstrated that molecules in adsorption layers virtually retain their translational degrees of freedom along the surfaces and the lowering of the diffusivity is mainly due to the geometric restriction rather than to the interaction with the surface.

TL;DR: A rapid-scan in vivo electron spin resonance (ESR) imaging system operating at 700 MHz based on an air-cored two-coil Helmholtz designed resistive magnet provided detailed spatiotemporal information on the distribution of the injected nitroxide radical in the rat head.

TL;DR: Elevated R2 and R1 (expressed in terms of the concentration of gadolinium per kg of tissue) can be accounted for in part by the lower water content of tissues compared with gels or solutions increased microviscosity and binding to macromolecules.

TL;DR: It is concluded that DSC using a SD FLASH sequence allows the simultaneous measurement of the AIF and the tissue concentration-time curve and thus an absolute quantification of the rCBV, which is the basis for interperson comparisons and follow-up studies.

TL;DR: The observed spatial and temporal patterns of R2* change support the view that the method is monitoring changes in neural activity.

TL;DR: A polysaccharide material, TX-151, has been used together with water, NaCl, and Al powder to create a tissue equivalent gel to make a realistic, inexpensive, conveniently moldable, temporally stable tissue equivalent MRI phantom.

TL;DR: High resolution magnetic resonance imaging technique to serially assess lesions of atherosclerosis in a rabbit model and wall thickness and lumen area derived noninvasively from the in vivo MR images correlate with postmortem MR images and sections of aorta examined by dissection microscopy and histology.

TL;DR: This preliminary study deals with the silicon functionality of MCM-41, a purely siliceous, amorphous and mesoporous silica, and results are found to be in perfect agreement with a binomial probability distribution of sites.

TL;DR: The diffusive-diffraction concept is extremely helpful in elucidating the Pulsed Gradient Spin Echo NMR experiment for fluid molecules in porous media and has been applied successfully to the model isolated pore and the orientationally disordered interconnected pore glass.

TL;DR: Segmentation of MR brain scans of 105 healthy children and adolescents showed that although the total brain volume was stable over age 4-18, white matter increased and gray matter decreased significantly, and white matter volume increased the most in superior and posterior regions and laterality effects were seen in hemisphere tissue volumes.

TL;DR: The effects of exposure in utero to high field (4.7 T) magnetic resonance imaging (MRI) conditions on fetal growth, adult growth, and testicular development in the mouse were investigated and significant differences in sensitive biological end points following in uterno exposure to complex MRI field conditions were found.