Journal of magnetic resonance imaging : JMRI
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J Magn Reson Imaging · Apr 2012
Hadamard-encoding combined with two-dimensional-selective radiofrequency excitations for flexible and efficient acquisitions of multiple voxels in MR spectroscopy.
To improve the efficiency and flexibility of acquisitions of multiple voxels in MR spectroscopy by combining two-dimensional-selective radiofrequency (2DRF) excitations and Hadamard encoding. ⋯ The presented approach improves the flexibility and efficiency of acquisitions of multiple voxels, i.e., can shorten acquisition times accordingly, and can help to reduce partial volume effects.
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J Magn Reson Imaging · Mar 2012
Proton MR spectroscopy in predicting the increase of perfusion MR imaging for WHO grade II gliomas.
To investigate the correlation between the metabolite ratios obtained from proton magnetic resonance (MR) spectroscopy and those obtained from MR perfusion parameters (relative cerebral blood volume [rCBV]) in a cohort of low-grade glioma (LGG). ⋯ This study demonstrated consistent correlations between the data from (1) HMRS and PWI. The Lac/Cr ratio predicts regional hemodynamic changes, which are themselves a useful biomarker of clinical prognosis in patients with LGG. As such, this ratio may provide a new parameter for making improved clinical decisions.
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J Magn Reson Imaging · Mar 2012
Radiology's ethical responsibility for healthcare reform: tempering the overutilization of medical imaging and trimming down a heavyweight.
In this review we describe the problem of overutilization of high-cost imaging modalities, especially magnetic resonance imaging (MRI) and computed tomography (CT). The overuse of CT is numerically more dramatic and also carries with it the not insignificant risk of harm to patients, namely, induction of radiation-induced malignancies. We report what is known of these risks in various imaging scenarios. ⋯ The imperative of appropriate utilization is focused on, with emphasis placed on computer-based medical decision support. Impediments to appropriate use, however, exist, with concerns of medicolegal liability high on the list of these issues. Finally, we recommend that radiologists take the lead in the reform process by implementing strategies such as decision support.
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To compare image quality including the number of perforators visualized, vessel contrast ratios, and vessel sharpness with blood pool and extracellular contrast agents in abdominal perforator flap magnetic resonance angiography (MRA). ⋯ Perforator MRA image quality including number of perforators visualized, perforator-to-muscle contrast, and vessel sharpness is higher with gadofosveset trisodium compared with gadobenate dimeglumine.
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J Magn Reson Imaging · Mar 2012
Measuring the neural response to continuous intramuscular infusion of hypertonic saline by perfusion MRI.
To determine the extent to which arterial spin labeling (ASL), a functional magnetic resonance imaging technique that directly measures cerebral blood flow (CBF), is able to measure the neural activation associated with prolonged experimental muscle pain. ⋯ This study demonstrates the ability of ASL to measure changes in CBF over extended periods of time and that the neural activation caused by muscle pain is paradigm specific.