RöFo : Fortschritte auf dem Gebiete der Röntgenstrahlen und der Nuklearmedizin
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This review presents the basic principles of functional imaging of the central nervous system utilizing magnetic resonance imaging. The focus is set on visualization of different functional aspects of the brain and related pathologies. Additionally, clinical cases are presented to illustrate the applications of functional imaging techniques in the clinical setting. ⋯ Based on different pharmacokinetic models of contrast enhancement diagnostic applications for neurology and radio-oncology are discussed. The functional non-contrast enhanced imaging techniques are based on "blood oxygenation level dependent (BOLD)-fMRI and arterial spin labeling (ASL) technique. They have gained clinical impact particularly in the fields of psychiatry and neurosurgery.
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Clinical Trial Controlled Clinical Trial
[Estimation of diffuse bone marrow infiltration of the spine in multiple myeloma: correlation of MRT with histological results].
To determine the detection of diffuse bone marrow infiltration with MRI in comparison with histopathological findings. ⋯ The sensitivity of the visual detection of diffuse multiple myeloma with unenhanced MRI is limited for low-grade or moderate infiltration, whereas the sensitivity for high grade infiltration is reliable. The specificity is high and the diagnostic confidence improves after application of contrast material with calculation of the percentage increase in signal intensity.
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MRI-imaging using a field strength above 2 Tesla -- recently termed "highfield MRI" -- has come into clinical use in the last three years. For technical reasons, the initial application of highfield MRI concentrated on examinations of the brain. By improving the technology and solving specific problems, it has now become possible to perform total body scans. ⋯ BOLD contrast fMRI, perfusion analysis and spectroscopy all seem to improve. For total body scanning, it is already possible to examine certain areas in "1.5 Tesla quality", in some cases shortening scanning time considerably. This survey summarises the present state of knowledge, realising that the presentation might not be all-comprising since progress in this field is very dynamic.
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Comparative Study Clinical Trial
[Systematic analysis of the geometry of a defined contrast medium bolus--implications for contrast enhanced 3D MR-angiography of thoracic vessels].
Little is known about the dispersion of a defined contrast bolus during its passage through the heart and pulmonary vasculature. The purpose of this study was to analyze factors influencing a defined contrast bolus for ce-MRA of thoracic vessels. ⋯ Analysis of bolus geometry enables determination of transit times of a defined contrast bolus through a defined target vessel in the thoracic cavity. Bolus geometry is mainly determined by injection parameters, cardiac function is of minor importance. Dispersion of contrast bolus and MTT increase from the pulmonary trunc to the ascending aorta. The knowledge of these facts may help optimizing of injection parameters and the total amount of contrast agent for contrast-enhanced MRA of thoracic vessels.
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Clinical Trial
[Contribution of early systole to total antegrade flow volume in breath-hold phase-contrast flow measurements].
To evaluate the contribution of early systole for the assessment of antegrade aortic flow volume by breath-hold velocity-encoded magnetic resonance (MR) flow measurements. ⋯ Flow during early systole contributes substantially to total forward flow volume in the ascending aorta. Interpolation of the early systolic up-slope is therefore recommended for the evaluation of breath-hold phase-contrast flow measurements.