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Find video protocols related to scientific articles indexed in Pubmed.
Multisite longitudinal reliability of tract-based spatial statistics in diffusion tensor imaging of healthy elderly subjects.
Neuroimage
PUBLISHED: 02-19-2014
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Large-scale longitudinal neuroimaging studies with diffusion imaging techniques are necessary to test and validate models of white matter neurophysiological processes that change in time, both in healthy and diseased brains. The predictive power of such longitudinal models will always be limited by the reproducibility of repeated measures acquired during different sessions. At present, there is limited quantitative knowledge about the across-session reproducibility of standard diffusion metrics in 3T multi-centric studies on subjects in stable conditions, in particular when using tract based spatial statistics and with elderly people. In this study we implemented a multi-site brain diffusion protocol in 10 clinical 3T MRI sites distributed across 4 countries in Europe (Italy, Germany, France and Greece) using vendor provided sequences from Siemens (Allegra, Trio Tim, Verio, Skyra, Biograph mMR), Philips (Achieva) and GE (HDxt) scanners. We acquired DTI data (2 × 2 × 2 mm(3), b = 700 s/mm(2), 5 b0 and 30 diffusion weighted volumes) of a group of healthy stable elderly subjects (5 subjects per site) in two separate sessions at least a week apart. For each subject and session four scalar diffusion metrics were considered: fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD) and axial (AD) diffusivity. The diffusion metrics from multiple subjects and sessions at each site were aligned to their common white matter skeleton using tract-based spatial statistics. The reproducibility at each MRI site was examined by looking at group averages of absolute changes relative to the mean (%) on various parameters: i) reproducibility of the signal-to-noise ratio (SNR) of the b0 images in centrum semiovale, ii) full brain test-retest differences of the diffusion metric maps on the white matter skeleton, iii) reproducibility of the diffusion metrics on atlas-based white matter ROIs on the white matter skeleton. Despite the differences of MRI scanner configurations across sites (vendors, models, RF coils and acquisition sequences) we found good and consistent test-retest reproducibility. White matter b0 SNR reproducibility was on average 7 ± 1% with no significant MRI site effects. Whole brain analysis resulted in no significant test-retest differences at any of the sites with any of the DTI metrics. The atlas-based ROI analysis showed that the mean reproducibility errors largely remained in the 2-4% range for FA and AD and 2-6% for MD and RD, averaged across ROIs. Our results show reproducibility values comparable to those reported in studies using a smaller number of MRI scanners, slightly different DTI protocols and mostly younger populations. We therefore show that the acquisition and analysis protocols used are appropriate for multi-site experimental scenarios.
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Non-invasive estimation of prostate cancer aggressiveness using diffusion-weighted MRI and 3D proton MR spectroscopy at 3.0?T.
Acta Radiol
PUBLISHED: 02-08-2014
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Clinical management of prostate cancer increasingly aims to distinguish aggressive types that require immediate and radical treatment from indolent tumors that are candidates for watchful waiting. This requires reliable and reproducible parameters to effectively control potential cancer progression. Magnetic resonance imaging (MRI) may provide a non-invasive means for this purpose.
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Bilateral hypertrophic olivary degeneration in Wilson disease.
Korean J Radiol
PUBLISHED: 02-22-2013
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Hypertrophic olivary degeneration resulting from lesions of the dento-rubro-olivary pathway, also called Guillain-Mollaret-triangle, has been described previously in a number of cases. Reports about bilateral hypertrophic olivary degeneration of the inferior olivary nuclei are very limited, and the magnetic resonance imaging findings of hypertrophic olivary degeneration in Wilson disease have not yet been described to the best of our knowledge. Herein, we present the first report of bilateral hypertrophic olivary degeneration diagnosed by magnetic resonance imaging in a patient suffering from Wilson disease.
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Novel technique for MR elastography of the prostate using a modified standard endorectal coil as actuator.
J Magn Reson Imaging
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To present a novel method for MR elastography (MRE) of the prostate at 3 Tesla using a modified endorectal imaging coil.
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Diagnostic value of ADC in patients with prostate cancer: influence of the choice of b values.
Eur Radiol
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To evaluate the influence of the choice of b values on the diagnostic value of the apparent diffusion coefficient (ADC) for detection and grading of prostate cancer (PCa).
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.