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Computer-processing complex

3D DT-MRI Data Visualisation using the Dual Tree Complex Wavelet Transform

Diffusion Tensor Magnetic Resonance Imaging (DT-MRI) is a speciffic modality of MRI which is based on the calculation
of the diffusion of water along dfferent directions within the brain. It can be used e±ciently to map white matter
tracts within the human brain. In previous work [1], we have shown how the Dual Tree Complex Wavelet Transform
[2], [3] can be used to visualise DT-MRI data in 2 dimensions. Our method produces images which contain more detail
than images developed using standard techniques [4], [5] and are also more easy to physically interpret. In this paper
we will present an extension of this method to 3 dimensions.

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Compressed Sensing MRI

Compressed sensing (CS) aims to reconstruct signals and images from significantly fewer measurements than were traditionally thought necessary. Magnetic Resonance Imaging (MRI) is an essentialedical imaging tool burdened by an inherently slow data acquisition process. The application of CS to MRI has the potential for significant scan time reductions, with benefits for patients and health care economics.


MRI obeys two key requirements for successful application of CS: (1) medical imagery is naturally compressible by sparse coding in an appropriate transform domain (e.g., by wavelet transform); (2) MRI scanners naturally acquire samples of the encoded image in spatial frequency, rather than direct pixel samples.


In this paper we review the requirements for successful CS, describe their natural fit to MRI, and then give examples of four interesting applications of CS in MRI. We emphasize an intuitive understanding of CS by describing the CS reconstruction as a process of interference cancellation. We also emphasize an understanding of the driving factors in applications, including limitations posed by MRI hardware, the characteristics of different types of images, and clinical concerns.

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A review of wavelet denoising in MRI and ultrasound brain imaging

There is a growing interest in using multiresolution noise filters in a variety of medical imaging applications. We review recent wavelet denoising techniques for medical ultrasound and for magnetic resonance images and discuss some of their potential applications in the clinical investigations of the brain. Our goal is to present and evaluate noise suppression methods based on both image processing and clinical expertise.

We analyze two types of filters for magnetic resonance images (MRI): noise suppression in magnitude MRI images and denoising blood oxygen level-dependent (BOLD) response in functional MRI images (fMRI). The noise distribution in magnitude MRI images is Rician, while the noise distribution in BOLD images has been recently shown to follow a Gaussian model well. We evaluate different methods based on signal to noise ratio improvement and based on the preservation of the shape of the activated regions in MRI.

A critical view on the problem of speckle filtering in ultrasound images is given where we discuss some of the issues that are overlooked in many speckle filters like the relevance of the “speckled texture”, expert-defined features of interest and the reliability of the common speckle models. We

analyze the use of multiresolution speckle filters to improve the automatic processing steps in the clinical research of non-cystic periventricular leukomalacia. In particular we apply speckle filters to ultrasound neonatal brain images and we evaluate the influence of the filtering on the effectiveness of the subsequent classification and segmentation of flares of affected tissue in comparison with the manual delineation of clinicians.

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Government and Politics

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For the first time computed tomography as a nondestructive method of study of the internal structure of the object appeared in the 70s of last century, and the theoretical foundations of their own appearance of this diagnostic method were laid in 20 years. Now it is difficult to imagine a modern high-tech...

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The "Public MRI scanner" at the beginning of this year was included on the proposal of the Siberian Branch RAS in the regions of Russia sent a list of innovative projects of the Academy of Sciences. Vologda Oblast Government first responded to the appeal of the Academy of Sciences to participate...

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April 30, 2010, T. Golikova, Minister of Health and Social Development In our country, laid a strong scientific tradition of nuclear technology, which, in turn, have strong potential for innovative development of domestic medicine. First of all, the development of nuclear medicine...

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Doctors and patients

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Magnetic resonance imaging (nuclear magnetic resonance imaging, MRI, NMRI, MRI, NMR) - is not radiological method of investigation of internal organs and tissues. It does not use X-rays, this method is safe for most people. As we study MRI technology is quite complex: using resonant absorption...

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The popularity of MRI computer tomography (CT) as a method of diagnosis in recent years has increased dramatically. In this regard, researchers are investigating the influence of ionizing radiation on the human body. In particular, recently published in the Archives of Internal Medicine, a study by Rita...

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Researchers from Peking University, experimentally determined which areas of the brain associated with perception of words, typically associated with death. The studies were first shown a curious response mechanism in the brain related topics. Specialists conducted a magnetic resonance imaging...

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Equipment and methods

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RZ Sagdeev (1), VI Krutskikh (2) A. Pirogov (3) 1) International...

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VI Krutskikh, Y. Pies, RZ Sagdeev Center for Magnetic...

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A comparison of the tomograms obtained by MRI "Unitom", "Philips", "Siemens", "General Electric"

Dear visitors of an open project "Public MRI scanner"! Invite...

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Economy & Business

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Supermortality. So the word is characterized by the demographic situation in Russia of the 21st century. Mortality in Russia is almost twice the global average ( Source). Worse than in Russia, the situation is in 21 countries, such as Chad, Zimbabwe, Liberia, Somalia... We consider ourselves...

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How much should cost scanner ???!!!

Onishchenko warns: X-rays are very harmful to your health!

Onishchenko warns: X-rays are very harmful to your health!
One survey in the X-ray machine gives you a charge of radiation, what would you have, being 2.4 km from Hiroshima in 1945. Than to replace it?

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