Academic radiology
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Randomized Controlled Trial Comparative Study
Enhancing lesions of the brain: intraindividual crossover comparison of contrast enhancement after gadobenate dimeglumine versus established gadolinium comparators.
Gadobenate dimeglumine (Gd-BOPTA) possesses a two-fold higher T1 relaxivity compared to other available gadolinium contrast agents. The study was conducted to evaluate the benefits of this increased relaxivity for MR imaging of intracranial enhancing brain lesions. ⋯ The greater T1 relaxivity of Gd-BOPTA permits improved visualization of intracranial enhancing lesions compared to conventional gadolinium agents.
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Controlled Clinical Trial
Inversion recovery MRI in idiopathic Parkinson disease is a very sensitive tool to assess neurodegeneration in the substantia nigra: preliminary investigation.
Segmented inversion recovery (IR) ratio imaging (SIRRIM) has been established as a sensitive tool to assess neurodegeneration of the substantia nigra pars compacta (SN(C)) in patients with idiopathic Parkinson disease (IPD). The obtained results suggest the possibility of magnetic resonance imaging (MRI) as a biological marker for IPD. The strength and a parsimonious analysis of the technique are discussed to assess the potential of using MRI as a biological marker for IPD and improve the differential diagnosis of sporadic Parkinson disease. Our hypothesis states that the magnetic resonance SIRRIM technique allows direct visualization and quantitation of neural cell loss in the SN(C) and therefore could become a reliable biological marker for Parkinson disease. To achieve this goal, some key aspects of data acquisition and data analysis need to be addressed. The clinical impact of the SIRRIM technique could be considerable, considering that it might become a viable surrogate to other techniques. ⋯ The hypothesis of using SIRRIM as a biological marker to assess IPD is supported by excellent correlation with clinical UPDRS scoring and has proved useful for the evaluation and quantitation of neurodegeneration with our SIRRIM technique, showing, in addition, that the differential diagnosis of IPD can be improved. Technical aspects of acquisition and data processing that need to be addressed can be overcome. It ultimately confirms that our objectives can be achieved and allows us to expect assessment of the progressive development of neurodegeneration in longitudinal studies and the putative neuroprotective approaches taken during the evolution of the disease.
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The aim of the study is to develop a theory-based signal calibration approach to be used for the conversion of signal-time curves to absolute contrast concentration-time curves for first-pass contrast-enhanced quantitative myocardial perfusion studies. ⋯ This theory-based signal calibration approach can be used to perform rapid T1 mapping and provides flexibility for in vivo calibration of signal-time curves resulting from dual-delay-time first-pass contrast-enhanced acquisitions.
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This review paper tracks the growth in the evidence supporting the use of percutaneous vertebroplasty for painful osteoporotic vertebral compression fractures. The rapidly increasing numbers of publications in the literature between 1994 and 2004 are documented. Despite the relatively large volume of research on this topic, several technology appraisals undertaken by international health policy makers reported inadequate high-quality evidence. Policy makers' reimbursement decisions for vertebroplasty and their options when faced with imperfect evidence are discussed.
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A near real-time and fully automatic method for calculation of the midsagittal plane (MSP) for magnetic resonance (MR) diffusion and perfusion images is introduced. ⋯ The proposed method is near real-time and fully automatic, and neither user interaction nor parameter setting is needed. It does not require preprocessing of data. The method potentially is useful in rapid and automated processing of MR stroke diffusion and perfusion images.