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Diffusion MRI

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5551: 737:, to indicate that the diffusion process is not free in tissues, but hindered and modulated by many mechanisms (restriction in closed spaces, tortuosity around obstacles, etc.) and that other sources of IntraVoxel Incoherent Motion (IVIM) such as blood flow in small vessels or cerebrospinal fluid in ventricles also contribute to the signal attenuation. At the end, images are "weighted" by the diffusion process: In those diffusion-weighted images (DWI) the signal is more attenuated the faster the diffusion and the larger the b factor is. However, those diffusion-weighted images are still also sensitive to T1 and T2 relaxivity contrast, which can sometimes be confusing. It is possible to calculate "pure" diffusion maps (or more exactly ADC maps where the ADC is the sole source of contrast) by collecting images with at least 2 different values, 5627: 2626:
diffusion leads to movement of water molecules along trajectories that proceed along multiple directions over time, leading to a complex projection onto the Cartesian axes. This pattern is reproducible if the same conditions and forces are applied to the same tissue in the same way. If there is an internal anisotropic organization of the tissue that constrains diffusion, then this fact will be reflected in the pattern of diffusion. The relationship between the properties of driving force that generate diffusion of the water molecules and the resulting pattern of their movement in the tissue can be described by a tensor. The collection of molecular displacements of this physical property can be described with nine components—each one associated with a pair of axes
2921:) describe the rotation of the ellipsoid relative to the orthogonal axes of the Cartesian coordinate system. These six variables can be represented by a matrix similar to the tensor matrix defined at the start of this section (since diffusion is symmetric, then we only need six instead of nine components—the components below the diagonal elements of the matrix are the same as the components above the diagonal). This is what is meant when it is stated that the components of a matrix of a second order tensor can be represented by an ellipsoid—if the diffusion values of the six terms of the quadric ellipsoid are placed into the matrix, this generates an ellipsoid angled off the orthogonal grid. Its shape will be more elongated if the relative anisotropy is high. 2393:. Diffusion itself is tensorial, but in many cases the objective is not really about trying to study brain diffusion per se, but rather just trying to take advantage of diffusion anisotropy in white matter for the purpose of finding the orientation of the axons and the magnitude or degree of anisotropy. Tensors have a real, physical existence in a material or tissue so that they do not move when the coordinate system used to describe them is rotated. There are numerous different possible representations of a tensor (of rank 2), but among these, this discussion focuses on the ellipsoid because of its physical relevance to diffusion and because of its historical significance in the development of diffusion anisotropy imaging in MRI. 963:
this condition, the ADC seems to depend on the choice of b values (the ADC seems to decrease when using larger b values), as the plot of ln(S/So) is not linear with the b factor, as expected from the above equations. This deviation from a free diffusion behavior is what makes diffusion MRI so successful, as the ADC is very sensitive to changes in tissue microstructure. On the other hand, modeling diffusion in tissues is becoming very complex. Among most popular models are the biexponential model, which assumes the presence of 2 water pools in slow or intermediate exchange and the cumulant-expansion (also called Kurtosis) model, which does not necessarily require the presence of 2 pools.
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gradient pulses, according to the Stejskal and Tanner method. This combination is not trivial, as cross-terms arise between all gradient pulses. The equation set by Stejskal and Tanner then becomes inaccurate and the signal attenuation must be calculated, either analytically or numerically, integrating all gradient pulses present in the MRI sequence and their interactions. The result quickly becomes very complex given the many pulses present in the MRI sequence, and as a simplification, Le Bihan suggested gathering all the gradient terms in a "b factor" (which depends only on the acquisition parameters) so that the signal attenuation simply becomes:
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six or more different diffusion weighted acquisitions, each obtained with a different orientation of the diffusion sensitizing gradients. In some methods, hundreds of measurements—each making up a complete image—are made to generate a single resulting calculated image data set. The higher information content of a DTI voxel makes it extremely sensitive to subtle pathology in the brain. In addition the directional information can be exploited at a higher level of structure to select and follow neural tracts through the brain—a process called
5566: 5655:. This vector can be color-coded, yielding a cartography of the tracts' position and direction (red for left-right, blue for superior-inferior, and green for anterior-posterior). The brightness is weighted by the fractional anisotropy which is a scalar measure of the degree of anisotropy in a given voxel. Mean diffusivity (MD) or trace is a scalar measure of the total diffusion within a voxel. These measures are commonly used clinically to localize white matter lesions that do not show up on other forms of clinical MRI. 314:
is applied in the same magnitude but with opposite direction to refocus or rephase the spins. The refocusing will not be perfect for protons that have moved during the time interval between the pulses, and the signal measured by the MRI machine is reduced. This "field gradient pulse" method was initially devised for NMR by Stejskal and Tanner who derived the reduction in signal due to the application of the pulse gradient related to the amount of diffusion that is occurring through the following equation:
200:(DBSI) further separates DTI signals into discrete anisotropic diffusion tensors and a spectrum of isotropic diffusion tensors to better differentiate sub-voxel cellular structures. For example, anisotropic diffusion tensors correlate to axonal fibers, while low isotropic diffusion tensors correlate to cells and high isotropic diffusion tensors correlate to larger structures (such as the lumen or brain ventricles). DBSI has been shown to differentiate some types of 2371:-value) and direction of the so-called magnetic diffusion gradient, as well as on the local microstructure in which the water molecules diffuse. The more attenuated the image is at a given position, the greater diffusion there is in the direction of the diffusion gradient. In order to measure the tissue's complete diffusion profile, one needs to repeat the MR scans, applying different directions (and possibly strengths) of the diffusion gradient for each scan. 9075: 3099: 5619: 5465: 5789:
maxima, pointing in opposite directions. If two tracts cross in the voxel, there will be two pairs of maxima, and so on. We can still use tensor mathematics to use the maxima to select groups of gradients to package into several different tensor ellipsoids in the same voxel, or use more complex higher-rank tensor analyses, or we can do a true "model free" analysis that picks the maxima, and then continue to do the tractography.
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This is often true, but it can be estimated that in more than 30% of the voxels in a standard resolution brain image, there are at least two different neural tracts traveling in different directions that pass through each other. In the classic diffusion ellipsoid tensor model, the information from the crossing tract appears as noise or unexplained decreased anisotropy in a given voxel.
135:) reflects the best estimate of the rate of water diffusion at that location. Because the mobility of water is driven by thermal agitation and highly dependent on its cellular environment, the hypothesis behind DWI is that findings may indicate (early) pathologic change. For instance, DWI is more sensitive to early changes after a stroke than more traditional MRI measurements such as 2320: 4349: 1792: 5351: 3961: 310:-weighted images, contrast is produced by measuring the loss of coherence or synchrony between the water protons. When water is in an environment where it can freely tumble, relaxation tends to take longer. In certain clinical situations, this can generate contrast between an area of pathology and the surrounding healthy tissue. 2588: 2932:" the matrix. This has two important meanings in imaging. The idea is that there are two equivalent ellipsoids—of identical shape but with different size and orientation. The first one is the measured diffusion ellipsoid sitting at an angle determined by the axons, and the second one is perfectly aligned with the three 1507: 5788:
to add more evenly spaced apices to the original icosahedron (20 faces)—an idea that also had its precedents in paleomagnetism research several decades earlier. We want to know which direction lines turn up the maximum anisotropic diffusion measures. If there is a single tract, there will be only two
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Diffusion tensor imaging (DTI) is a magnetic resonance imaging technique that enables the measurement of the restricted diffusion of water in tissue in order to produce neural tract images instead of using this data solely for the purpose of assigning contrast or colors to pixels in a cross-sectional
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leads to diffusion restriction, and the difference between images with various DWI weighting will therefore be minor, leading to an ADC image with low signal in the infarcted area. A decreased ADC may be detected minutes after a cerebral infarction. The high signal of infarcted tissue on conventional
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can also be investigated using MR spectroscopic approaches). MRI can be made sensitive to the motion of molecules. Regular MRI acquisition utilizes the behavior of protons in water to generate contrast between clinically relevant features of a particular subject. The versatile nature of MRI is due to
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it is usually necessary to know only the magnitude and orientation of the primary axis or vector. This primary axis—the one with the greatest length—is the largest eigenvalue and its orientation is encoded in its matched eigenvector. Only one axis is needed as it is assumed the largest eigenvalue is
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are "off diagonal". It then becomes possible to do a vector processing step in which we rewrite our matrix and replace it with a new matrix multiplied by three different vectors of unit length (length=1.0). The matrix is diagonalized because the off-diagonal components are all now zero. The rotation
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A tensor is often a physical or biophysical property that determines the relationship between two vectors. When a force is applied to an object, movement can result. If the movement is in a single direction, the transformation can be described using a vector—a tensor of rank 1. However, in a tissue,
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that is otherwise inherent to conventional DWI. ADC imaging does so by acquiring multiple conventional DWI images with different amounts of DWI weighting, and the change in signal is proportional to the rate of diffusion. Contrary to DWI images, the standard grayscale of ADC images is to represent a
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To sensitize MRI images to diffusion, the magnetic field strength (B1) is varied linearly by a pulsed field gradient. Since precession is proportional to the magnet strength, the protons begin to precess at different rates, resulting in dispersion of the phase and signal loss. Another gradient pulse
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tumors, and also to monitor tumor response to treatment over time. DWI can also be collected to visualize the whole body using a technique called 'diffusion-weighted whole-body imaging with background body signal suppression' (DWIBS). Some more specialized diffusion MRI techniques such as diffusion
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if the medium is anisotropic (it would be the surface of a sphere for an isotropic medium). The ellipsoid formalism functions also as a mathematical method of organizing tensor data. Measurement of an ellipsoid tensor further permits a retrospective analysis, to gather information about the process
3056:" or characteristic vectors. They contain the orientation information of the original ellipsoid. The three axes of the ellipsoid are now directly along the main orthogonal axes of the coordinate system so we can easily infer their lengths. These lengths are the eigenvalues or characteristic values. 2665:
Diffusion from a point source in the anisotropic medium of white matter behaves in a similar fashion. The first pulse of the Stejskal Tanner diffusion gradient effectively labels some water molecules and the second pulse effectively shows their displacement due to diffusion. Each gradient direction
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In DTI, each voxel has one or more pairs of parameters: a rate of diffusion and a preferred direction of diffusion—described in terms of three-dimensional space—for which that parameter is valid. The properties of each voxel of a single DTI image are usually calculated by vector or tensor math from
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In order to localize this signal attenuation to get images of diffusion one has to combine the pulsed magnetic field gradient pulses used for MRI (aimed at localization of the signal, but those gradient pulses are too weak to produce a diffusion related attenuation) with additional "motion-probing"
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Early in the development of DTI based tractography, a number of researchers pointed out a flaw in the diffusion tensor model. The tensor analysis assumes that there is a single ellipsoid in each imaging voxel—as if all of the axons traveling through a voxel traveled in exactly the same direction.
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Although this ADC concept has been extremely successful, especially for clinical applications, it has been challenged recently, as new, more comprehensive models of diffusion in biological tissues have been introduced. Those models have been made necessary, as diffusion in tissues is not free. In
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of some crystals. Water will then diffuse more rapidly in the direction aligned with the internal structure (axial diffusion), and more slowly as it moves perpendicular to the preferred direction (radial diffusion). This also means that the measured rate of diffusion will differ depending on the
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which is the square root of the sum of squares (SRSS) of the diffusivity differences, divided by the SRSS of the diffusivities. When the second and third axes are small relative to the principal axis, the number in the numerator is almost equal the number in the denominator. We also multiply by
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applied a heated point to a polished crystal surface that had been coated with wax. In some materials that had "isotropic" structure, a ring of melt would spread across the surface in a circle. In anisotropic crystals the spread took the form of an ellipse. In three dimensions this spread is an
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Note, there is ongoing debate about the best way to preprocess DW-MRI. Several in-vivo studies have shown that the choice of software and functions applied (directed at correcting artefacts arising from e.g. motion and eddy-currents) have a meaningful impact on the DTI parameter estimates from
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The Q-Ball method of tractography is an implementation in which David Tuch provides a mathematical alternative to the tensor model. Instead of forcing the diffusion anisotropy data into a group of tensors, the mathematics used deploys both probability distributions and some classic geometric
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and major brain nuclei, or in the body—where the diffusion rate appears to be the same when measured along any axis. However, DWI also remains sensitive to T1 and T2 relaxation. To entangle diffusion and relaxation effects on image contrast, one may obtain quantitative images of the diffusion
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The idea of a tensor in physical science evolved from attempts to describe the quantity of physical properties. The first properties they were applied to were those that can be described by a single number, such as temperature. Properties that can be described this way are called
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provides a mathematical basis for passing a large number of evenly spaced gradient trajectories through the voxel—each coinciding with one of the apices of the icosahedron. We can then look into the voxel from a large number of different directions (typically 40 or more). We use
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is the diffusion tensor. Aside from describing the amount of diffusion, it is often important to describe the relative degree of anisotropy in a voxel. At one extreme would be the sphere of isotropic diffusion and at the other extreme would be a cigar or pencil shaped very thin
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Once we have measured the voxel from six or more directions and corrected for attenuations due to T2 and T1 effects, we can use information from our calculated ellipsoid tensor to describe what is happening in the voxel. If you consider an ellipsoid sitting at an angle in a
5154: 4025:). However, this proves to be very susceptible to measurement noise, so increasingly complex measures were developed to capture the measure while minimizing the noise. An important element of these calculations is the sum of squares of the diffusivity differences = ( 2607:; these can be considered tensors of rank 0, or 0th-order tensors. Tensors can also be used to describe quantities that have directionality, such as mechanical force. These quantities require specification of both magnitude and direction, and are often represented with a 2593:
The same matrix of numbers can have a simultaneous second use to describe the shape and orientation of an ellipse and the same matrix of numbers can be used simultaneously in a third way for matrix mathematics to sort out eigenvectors and eigenvalues as explained below.
5705:). Tractography is a useful tool for measuring deficits in white matter, such as in aging. Its estimation of fiber orientation and strength is increasingly accurate, and it has widespread potential implications in the fields of cognitive neuroscience and neurobiology. 1955: 6185:
Vavasour, Irene M; Sun, Peng; Graf, Carina; Yik, Jackie T; Kolind, Shannon H; Li, David KB; Tam, Roger; Sayao, Ana-Luiza; Schabas, Alice; Devonshire, Virginia; Carruthers, Robert; Traboulsee, Anthony; Moore, GR Wayne; Song, Sheng-Kwei; Laule, Cornelia (March 2022).
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variations in the MRI magnet) are applied that can determine at least 3 directional vectors (use of 6 different gradients is the minimum and additional gradients improve the accuracy for "off-diagonal" information), it is possible to calculate, for each
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The fractional anisotropy can also be separated into linear, planar, and spherical measures depending on the "shape" of the diffusion ellipsoid. For example, a "cigar" shaped prolate ellipsoid indicates a strongly linear anisotropy, a "flying saucer" or
2402: 3336:. In the setting of the DTI tensor ellipsoid, we can consider each of these as a measure of the diffusivity along each of the three primary axes of the ellipsoid. This is a little different from the ADC since that was a projection on the axis, while 147:(DSI), was used in deriving the Connectome data sets; DSI is a variant of diffusion-weighted imaging that is sensitive to intra-voxel heterogeneities in diffusion directions caused by crossing fiber tracts and thus allows more accurate mapping of 5449: 4836: 3437:
This quantity is an assessment of the degree of restriction due to membranes and other effects and proves to be a sensitive measure of degenerative pathology in some neurological conditions. It can also be called the perpendicular diffusivity
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The ellipsoid itself has a principal long axis and then two more small axes that describe its width and depth. All three of these are perpendicular to each other and cross at the center point of the ellipsoid. We call the axes in this setting
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for magnetization would change with the addition of diffusion. Torrey modified Bloch's original description of transverse magnetization to include diffusion terms and the application of a spatially varying gradient. Since the magnetization
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Ye, Zezhong; Price, Richard L.; Liu, Xiran; Lin, Joshua; Yang, Qingsong; Sun, Peng; Wu, Anthony T.; Wang, Liang; Han, Rowland H.; Song, Chunyu; Yang, Ruimeng; Gary, Sam E.; Mao, Diane D.; Wallendorf, Michael; Campian, Jian L. (2020-10-15).
4667: 4067:). We use the square root of the sum of squares to obtain a sort of weighted average—dominated by the largest component. One objective is to keep the number near 0 if the voxel is spherical but near 1 if it is elongate. This leads to the 2077: 1307: 5550: 175:
coefficient, or more exactly the apparent diffusion coefficient (ADC). The ADC concept was introduced to take into account the fact that the diffusion process is complex in biological tissues and reflects several different mechanisms.
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applied measures the movement along the direction of that gradient. Six or more gradients are summed to get all the measurements needed to fill in the matrix, assuming it is symmetric above and below the diagonal (red subscripts).
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Recently, more advanced models of the diffusion process have been proposed that aim to overcome the weaknesses of the diffusion tensor model. Amongst others, these include q-space imaging and generalized diffusion tensor imaging.
4986: 4344:{\displaystyle \mathrm {FA} ={\frac {\sqrt {3((\lambda _{1}-\operatorname {E} )^{2}+(\lambda _{2}-\operatorname {E} )^{2}+(\lambda _{3}-\operatorname {E} )^{2})}}{\sqrt {2(\lambda _{1}^{2}+\lambda _{2}^{2}+\lambda _{3}^{2})}}}} 227:. The diffusion tensor model is a rather simple model of the diffusion process, assuming homogeneity and linearity of the diffusion within each image voxel. From the diffusion tensor, diffusion anisotropy measures such as the 1284: 3546: 1185: 4441: 2936:
axes. The term "diagonalize" refers to the three components of the matrix along a diagonal from upper left to lower right (the components with red subscripts in the matrix at the start of this section). The variables
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Makris N, Worth AJ, Sorensen AG, Papadimitriou GM, Wu O, Reese TG, et al. (December 1997). "Morphometry of in vivo human white matter association pathways with diffusion-weighted magnetic resonance imaging".
3122:, water molecules are moving due to diffusion and they move at equal rates in all directions. By knowing the detailed effects of diffusion gradients we can generate a formula that allows us to convert the signal 283:-weighted image, water molecules in a sample are excited with the imposition of a strong magnetic field. This causes many of the protons in water molecules to precess simultaneously, producing signals in MRI. In 4507: 5708:
The use of DTI for the assessment of white matter in development, pathology and degeneration has been the focus of over 2,500 research publications since 2005. It promises to be very helpful in distinguishing
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Niendorf T, Dijkhuizen RM, Norris DG, van Lookeren Campagne M, Nicolay K (December 1996). "Biexponential diffusion attenuation in various states of brain tissue: implications for diffusion-weighted imaging".
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More extended DTI scans derive neural tract directional information from the data using 3D or multidimensional vector algorithms based on six or more gradient directions, sufficient to compute the diffusion
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Le Bihan D, Breton E, Lallemand D, Grenier P, Cabanis E, Laval-Jeantet M (November 1986). "MR imaging of intravoxel incoherent motions: application to diffusion and perfusion in neurologic disorders".
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of a matrix is done by finding a second matrix that it can be multiplied with followed by multiplication by the inverse of the second matrix—wherein the result is a new matrix in which three diagonal (
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Wade, Ryckie G.; Tam, Winnie; Perumal, Antonia; Pepple, Sophanit; Griffiths, Timothy T.; Flather, Robert; Haroon, Hamied A.; Shelley, David; Plein, Sven; Bourke, Grainne; Teh, Irvin (2023-10-13).
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Traditionally, in diffusion-weighted imaging (DWI), three gradient-directions are applied, sufficient to estimate the trace of the diffusion tensor or 'average diffusivity', a putative measure of
3761: 3284: 5565: 2883: 5346:{\displaystyle \mathrm {RA} ={\frac {\sqrt {(\lambda _{1}-\operatorname {E} )^{2}+(\lambda _{2}-\operatorname {E} )^{2}+(\lambda _{3}-\operatorname {E} )^{2}}}{{\sqrt {3}}\operatorname {E} }}} 444: 5583:. Tumors are in many instances highly cellular, giving restricted diffusion of water, and therefore appear with a relatively high signal intensity in DWI. DWI is commonly used to detect and 3956:{\displaystyle {\begin{aligned}\mathrm {tr} (\Lambda )/3&=\mathrm {tr} (V^{-1}V\Lambda )/3\\&=\mathrm {tr} (V\Lambda V^{-1})/3\\&=\mathrm {tr} (D)/3\\&=ADC_{i}\end{aligned}}} 2185: 1085: 3361:. Historically, this is closest to what Richards originally measured with the vector length in 1991. The diffusivities in the two minor axes are often averaged to produce a measure of 6334:
Ye, Zezhong; Srinivasa, Komal; Meyer, Ashely; Sun, Peng; Lin, Joshua; Viox, Jeffrey D.; Song, Chunyu; Wu, Anthony T.; Song, Sheng-Kwei; Dahiya, Sonika; Rubin, Joshua B. (2021-02-26).
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In present-day clinical neurology, various brain pathologies may be best detected by looking at particular measures of anisotropy and diffusivity. The underlying physical process of
2752: 2583:{\displaystyle {\bar {D}}={\begin{vmatrix}D_{\color {red}xx}&D_{xy}&D_{xz}\\D_{xy}&D_{\color {red}yy}&D_{yz}\\D_{xz}&D_{yz}&D_{\color {red}zz}\end{vmatrix}}} 6660:
Liu C, Bammer R, Moseley ME (2003). "Generalized Diffusion Tensor Imaging (GDTI): A Method for Characterizing and Imaging Diffusion Anisotropy Caused by Non-Gaussian Diffusion".
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David Tuch was among the first to describe a solution to this problem. The idea is best understood by conceptually placing a kind of geodesic dome around each image voxel. This
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de Sénarmont HH (1848). "Mémoire sur la conductibilité des substances cristalisées pour la chaleur" [Memoir on the conductivity of crystallized substances for heat].
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Wedeen VJ, Wang RP, Schmahmann JD, Benner T, Tseng WY, Dai G, et al. (July 2008). "Diffusion spectrum magnetic resonance imaging (DSI) tractography of crossing fibers".
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represents diffusion in a plane, and a sphere is indicative of isotropic diffusion, equal in all directions. If the eigenvalues of the diffusion vector are sorted such that
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Le Bihan, Denis; Breton, E. (1985). "Imagerie de diffusion in-vivo par résonance magnétique nucléaire" [In-vivo diffusion imaging by nuclear magnetic resonance].
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method that produces in vivo magnetic resonance images of biological tissues sensitized with the local characteristics of molecular diffusion, generally water (but other
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of the brain as well as for studies of other body tissues (see below). DWI is most applicable when the tissue of interest is dominated by isotropic water movement e.g.
4575: 3569: 1502:{\displaystyle {\frac {d{\vec {M}}}{dt}}=\gamma {\vec {M}}\times {\vec {B}}-{\frac {M_{x}{\vec {i}}+M_{y}{\vec {j}}}{T_{2}}}-{\frac {(M_{z}-M_{0}){\vec {k}}}{T_{1}}}} 578: 558: 514: 3025: 2995: 2965: 2218: 1966: 104:. Water molecule diffusion patterns can therefore reveal microscopic details about tissue architecture, either normal or in a diseased state. A special kind of DWI, 6287:"Diffusion Histology Imaging Combining Diffusion Basis Spectrum Imaging (DBSI) and Machine Learning Improves Detection and Classification of Glioblastoma Pathology" 6235:
Ye, Zezhong; George, Ajit; Wu, Anthony T.; Niu, Xuan; Lin, Joshua; Adusumilli, Gautam; Naismith, Robert T.; Cross, Anne H.; Sun, Peng; Song, Sheng-Kwei (May 2020).
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in relation to the white matter tracts (infiltration, deflection), has been one of the most important initial applications. In surgical planning for some types of
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Manenti G, Carlani M, Mancino S, Colangelo V, Di Roma M, Squillaci E, Simonetti G (June 2007). "Diffusion tensor magnetic resonance imaging of prostate cancer".
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grid then you can consider the projection of that ellipse onto the three axes. The three projections can give you the ADC along each of the three axes ADC
1200: 231:(FA), can be computed. Moreover, the principal direction of the diffusion tensor can be used to infer the white-matter connectivity of the brain (i.e. 3478: 2367:
A more precise statement of the image acquisition process is that the image-intensities at each position are attenuated, depending on the strength (
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Griffiths, Timothy T.; Flather, Robert; Teh, Irvin; Haroon, Hamied A.; Shelley, David; Plein, Sven; Bourke, Grainne; Wade, Ryckie G. (2021-07-22).
4357: 3149:. The ADC in anisotropic tissue varies depending on the direction in which it is measured. Diffusion is fast along the length of (parallel to) an 6887:"Signal evolution and infarction risk for apparent diffusion coefficient lesions in acute ischemic stroke are both time- and perfusion-dependent" 208:
with higher specificity and sensitivity than conventional DTI. DBSI has also been useful in determining microstructure properties of the brain.
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Le Bihan D, Mangin JF, Poupon C, Clark CA, Pappata S, Molko N, Chabriat H (April 2001). "Diffusion tensor imaging: concepts and applications".
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The most common application of conventional DWI (without DTI) is in acute brain ischemia. DWI directly visualizes the ischemic necrosis in
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image. It also provides useful structural information about muscle—including heart muscle—as well as other tissues such as the prostate.
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Stejskal EO, Tanner JE (1 January 1965). "Spin Diffusion Measurements: Spin Echoes in the Presence of a Time-Dependent Field Gradient".
5753:: metrics derived from DTI (FA and RD) can differentiate asymptomatic adults from those with compression of the ulnar nerve at the elbow 4848: 8903: 3370: 8175: 6850:
Le Bihan D (August 2013). "Apparent diffusion coefficient and beyond: what diffusion MR imaging can tell us about tissue structure".
6188:"Characterization of multiple sclerosis neuroinflammation and neurodegeneration with relaxation and diffusion basis spectrum imaging" 4679: 4519: 154:
Diffusion-weighted images are very useful to diagnose vascular strokes in the brain. It is also used more and more in the staging of
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Westin CF, Maier SE, Mamata H, Nabavi A, Jolesz FA, Kikinis R (June 2002). "Processing and visualization for diffusion tensor MRI".
9011: 5149:{\displaystyle C_{a}=C_{l}+C_{p}=1-C_{s}={\frac {\lambda _{1}+\lambda _{2}-2\lambda _{3}}{\lambda _{1}+\lambda _{2}+\lambda _{3}}}} 3145:, because the measurement misses all the local effects and treats the attenuation as if all the movement rates were solely due to 8541: 7462:
Takahara, Taro; Kwee, Thomas C. (2010). "Diffusion-Weighted Whole-Body Imaging with Background Body Signal Suppression (DWIBS)".
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subscript to signify that this is what the isotropic diffusion coefficient would be with the effects of anisotropy averaged out.
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Taylor DG, Bushell MC (April 1985). "The spatial mapping of translational diffusion coefficients by the NMR imaging technique".
7773:"Meta-analysis of the normal diffusion tensor imaging values of the median nerve and how they change in carpal tunnel syndrome" 7992:
Basser PJ, Pajevic S (2007). "Spectral decomposition of a 4th-order covariance tensor: applications to diffusion tensor MRI".
7557:"Diffusion Tensor Imaging for Diagnosing Root Avulsions in Traumatic Adult Brachial Plexus Injuries: A Proof-of-Concept Study" 7497:"Diffusion kurtosis MRI as a predictive biomarker of response to neoadjuvant chemotherapy in high grade serous ovarian cancer" 1950:{\displaystyle {\vec {D}}=D\cdot {\vec {I}}=D\cdot {\begin{bmatrix}1&0&0\\0&1&0\\0&0&1\end{bmatrix}},} 610: 162:
as the 'gold standard' for this type of disease. Diffusion tensor imaging is being developed for studying the diseases of the
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can differentiate normal nerves (as shown in the tractogram of the spinal cord and brachial plexus and 3D 4k reconstruction
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and non-invasively. Molecular diffusion in tissues is not random, but reflects interactions with many obstacles, such as
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as well as software that generates images from the resulting data that uses the diffusion of water molecules to generate
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King MD, Houseman J, Roussel SA, van Bruggen N, Williams SR, Gadian DG (December 1994). "q-Space imaging of the brain".
2784: 2105:. Anisotropic diffusion will have a similar solution for the diffusion tensor, except that what will be measured is the 8939: 8818: 8558: 8467: 6443:
Zhang Y, Wang S, Wu L, Huo Y (Jan 2011). "Multi-channel diffusion tensor image registration via adaptive chaotic PSO".
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At this point, it is helpful to consider the mathematics of ellipsoids. An ellipsoid can be described by the formula:
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tissue. Consequently, this is the topic of a multinational study directed by the diffusion-study group of the ISMRM.
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of the water molecules preferentially along their main direction. Such preferentially oriented diffusion is called
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kurtosis imaging (DKI) have also been shown to predict the response of cancer patients to chemotherapy treatment.
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this capability of producing contrast related to the structure of tissues at the microscopic level. In a typical
7141: 1025: 8823: 8670: 8570: 8553: 7427:
Koh DM, Collins DJ (June 2007). "Diffusion-weighted MRI in the body: applications and challenges in oncology".
5864: 5486: 5482: 8766: 5651:) that describes the 3-dimensional shape of diffusion. The fiber direction is indicated by the tensor's main 3040:
angles required to get to this equivalent position now appear in the three vectors and can be read out as the
8949: 8803: 8402: 8277: 8269: 8168: 5689:
within white matter. Fiber tracking algorithms can be used to track a fiber along its whole length (e.g. the
6935: 5521:
in the form of a cytotoxic edema, appearing as a high DWI signal within minutes of arterial occlusion. With
2689: 9060: 8994: 8926: 8916: 8894: 8665: 8633: 8264: 5571:
DWI showing cortical ribbon-like high signal consistent with diffusion restriction in a patient with known
1829:
For the simplest case where the diffusion is isotropic the diffusion tensor is a multiple of the identity:
159: 6689:
Relevance of the information about the diffusion distribution in invo given by kurtosis in q-space imaging
6393:"Nucleus accumbens microstructure mediates the relationship between obesity and eating behavior in adults" 3110:
causes a group of water molecules to move out from a central point, and gradually reach the surface of an
2670: 2385:
Diffusion MRI relies on the mathematics and physical interpretations of the geometric quantities known as
8724: 8692: 8675: 4011:. The simplest measure is obtained by dividing the longest axis of the ellipsoid by the shortest = ( 3158: 2933: 2678:
showed in the 1850s, diffusion exhibits many of the same patterns as those seen in the transfer of heat.
1012: 5634:
The imaging of this property is an extension of diffusion MRI. If a series of diffusion gradients (i.e.
8798: 8533: 8273: 3441: 155: 6237:"Deep learning with diffusion basis spectrum imaging for classification of multiple sclerosis lesions" 9039: 8707: 8697: 8014: 5444:{\displaystyle \mathrm {VR} ={\frac {\lambda _{1}\lambda _{2}\lambda _{3}}{\operatorname {E} ^{3}}}} 4831:{\displaystyle C_{p}={\frac {2(\lambda _{2}-\lambda _{3})}{\lambda _{1}+\lambda _{2}+\lambda _{3}}}} 9078: 9029: 8808: 8687: 8660: 8421: 8206: 8161: 7149:. Proceedings of the Society for Magnetic Resonance in Medicine. Vol. 11. Berlin. p. 412. 5740: 4081: 2335:, is an MRI image that more specifically shows diffusion than conventional DWI, by eliminating the 50: 7160:
Vaillancourt DE, Spraker MB, Prodoehl J, Abraham I, Corcos DM, Zhou XJ, et al. (April 2009).
6513:
Posse S, Cuenod CA, Le Bihan D (September 1993). "Human brain: proton diffusion MR spectroscopy".
3628: 3601: 3574: 2928:, we can apply a useful technique from standard matrix mathematics and linear algebra—that is to " 2309:
The standard grayscale of DWI images is to represent increased diffusion restriction as brighter.
8977: 8813: 8754: 8739: 8628: 8450: 8426: 5750: 5557: 5475: 4662:{\displaystyle C_{l}={\frac {\lambda _{1}-\lambda _{2}}{\lambda _{1}+\lambda _{2}+\lambda _{3}}}} 3179:. This leads to the idea of describing the average diffusivity in the voxel which will simply be 5871:, and so on, but the generality, which covers arrays of all sizes, may obscure rather than help. 1800: 8848: 8717: 8648: 8455: 8009: 7918:"High angular resolution diffusion imaging reveals intravoxel white matter fiber heterogeneity" 7162:"High-resolution diffusion tensor imaging in the substantia nigra of de novo Parkinson disease" 5760: 5756: 5710: 2380: 2319: 2072:{\displaystyle {M}={M}_{\text{bloch}}e^{-{\frac {1}{3}}\gamma ^{2}G^{2}t^{3}D}\sim e^{-bD_{0}}} 5923:
Merboldt KD, Hanicke W, Frahm J (1985). "Self-diffusion NMR imaging using stimulated echoes".
3554: 189:
in the brain or muscle fibers in the heart—has an internal fibrous structure analogous to the
9109: 8712: 8643: 8509: 8392: 8311: 8218: 4069: 3127: 3059: 1546: 1091: 563: 543: 499: 228: 3141:
interfere with the free diffusion, we are measuring an "apparent diffusion coefficient", or
3000: 2970: 2940: 2193: 9055: 8744: 8682: 8504: 8001: 7784: 7508: 6768: 6557: 6347: 5967: 5932: 5798: 5648: 2925: 2611:. A three-dimensional vector can be described with three components: its projection on the 2604: 2277: 2250: 2223: 974: 767: 740: 452: 286: 259: 5759:: Metrics derived from DTI (lower FA and MD) differentiate healthy adults from those with 8: 9001: 8879: 8702: 8438: 7965:
Hext GR (1963). "The estimation of second-order tensors with related tests and designs".
5690: 5679: 5542: 5526: 5518: 3119: 2343: 2336: 1095: 714: 101: 8005: 7788: 7555:
Wade RG, Tanner SF, Teh I, Ridgway JP, Shelley D, Chaka B, et al. (16 April 2020).
7512: 6772: 6561: 6351: 6011:"Mapping complex tissue architecture with diffusion spectrum magnetic resonance imaging" 5971: 5936: 5817:, matrix mathematics and vector mathematics to process the analysis of the tensor data. 8989: 8838: 8833: 8734: 8617: 8472: 8223: 8123: 8086:"Comparison of distortion correction preprocessing pipelines for DTI in the upper limb" 8066: 8027: 7947: 7870: 7813: 7772: 7748: 7715: 7691: 7666: 7632: 7583: 7556: 7529: 7496: 7495:
Deen SS, Priest AN, McLean MA, Gill AB, Brodie C, Crawford R, et al. (July 2019).
7404: 7377: 7285: 7260: 7186: 7177: 7161: 7122: 6996: 6974: 6911: 6886: 6741: 6636: 6629:
Principles and Application of Self-Diffusion Measurements by Nuclear Magnetic Resonance
6609: 6495: 6417: 6392: 6368: 6335: 6311: 6286: 6261: 6236: 6212: 6187: 6162: 6137: 6083: 6040: 5991: 3989: 3969: 2088: 1527: 1191: 994: 694: 583: 523: 517: 479: 252: 215:. Clinically, trace-weighted images have proven to be very useful to diagnose vascular 205: 89: 7237: 2622:
axes. Vectors of this sort can be considered tensors of rank 1, or 1st-order tensors.
8828: 8793: 8788: 8729: 8477: 8326: 8127: 8115: 8107: 8070: 7939: 7898: 7862: 7818: 7800: 7753: 7735: 7696: 7665:
Wade RG, Whittam A, Teh I, Andersson G, Yeh FC, Wiberg M, Bourke G (9 October 2020).
7624: 7588: 7534: 7475: 7444: 7409: 7378:"Magnetic resonance diffusion-perfusion mismatch in acute ischemic stroke: An update" 7331: 7290: 7241: 7191: 7114: 7060: 7037: 6988: 6916: 6867: 6733: 6692: 6640: 6601: 6530: 6487: 6422: 6373: 6336:"Diffusion histology imaging differentiates distinct pediatric brain tumor histology" 6316: 6266: 6217: 6167: 6118: 6075: 6071: 6032: 5995: 5983: 5979: 5944: 4981:{\displaystyle C_{s}={\frac {3\lambda _{3}}{\lambda _{1}+\lambda _{2}+\lambda _{3}}}} 81: 7652:"DTI (Quantitative), a new and advanced MRI procedure for evaluation of Concussions" 7636: 7350: 7000: 6745: 6613: 6526: 6499: 6114: 2662:. These can be written as a matrix similar to the one at the start of this section. 219:
in the brain, by early detection (within a couple of minutes) of the hypoxic edema.
9104: 9099: 8655: 8514: 8286: 8238: 8097: 8058: 8031: 8019: 7974: 7951: 7929: 7874: 7852: 7808: 7792: 7743: 7727: 7686: 7678: 7616: 7578: 7568: 7524: 7516: 7467: 7436: 7399: 7389: 7321: 7280: 7272: 7233: 7181: 7173: 7126: 7106: 7027: 6978: 6970: 6906: 6898: 6859: 6776: 6723: 6669: 6632: 6593: 6565: 6522: 6479: 6452: 6412: 6404: 6363: 6355: 6306: 6298: 6256: 6248: 6207: 6199: 6157: 6149: 6110: 6087: 6067: 6044: 6022: 5975: 5940: 4008: 2675: 2608: 2390: 6302: 8864: 8316: 8282: 8255: 8250: 8184: 8023: 7916:
Tuch DS, Reese TG, Wiegell MR, Makris N, Belliveau JW, Wedeen VJ (October 2002).
7471: 6902: 6798: 5736: 4447: 3146: 2323:
ADC image of the same case of cerebral infarction as seen on DWI in section above
1520: 1279:{\displaystyle {\frac {\partial \rho (x,t)}{\partial t}}=D\nabla ^{2}\rho (x,t).} 171: 56: 7978: 7889: 6673: 9006: 7796: 7731: 7682: 7520: 7326: 7309: 7308:
Grand S, Tahon F, Attye A, Lefournier V, Le Bas JF, Krainik A (December 2013).
7276: 6359: 5814: 5718: 5635: 5584: 5572: 1299: 7771:
Rojoa, Djamila; Raheman, Firas; Rassam, Joseph; Wade, Ryckie G. (2021-10-22).
7143:
Vector analysis of diffusion images in experimental allergic encephalomyelitis
6203: 6136:
Wang Y, Wang Q, Haldar JP, Yeh FC, Xie M, Sun P, et al. (December 2011).
5556:
DWI showing restricted diffusion in the medial dorsal thalami consistent with
3541:{\displaystyle \mathrm {tr} (\Lambda )=\lambda _{1}+\lambda _{2}+\lambda _{3}} 1180:{\displaystyle {\frac {\partial \rho (x,t)}{\partial t}}=-\nabla \cdot J(x,t)} 9093: 8638: 8607: 8595: 8348: 8243: 8111: 7804: 7739: 7573: 7064: 7057:
Physical Properties of Crystals: Their Representation by Tensors and Matrices
6582: 5785: 5522: 4436:{\textstyle \operatorname {E} =(\lambda _{1}+\lambda _{2}+\lambda _{3})/3\,.} 3134: 1295: 140: 136: 97: 7902: 6863: 6780: 6696: 6456: 9021: 8874: 8869: 8776: 8600: 8585: 8519: 8119: 7943: 7866: 7822: 7757: 7700: 7592: 7538: 7448: 7413: 7335: 7294: 7245: 7195: 7118: 7041: 6992: 6920: 6871: 6737: 6631:. Advances in Magnetic and Optical Resonance. Vol. 12. pp. 1–89. 6597: 6483: 6426: 6377: 6320: 6270: 6221: 6171: 6153: 6138:"Quantification of increased cellularity during inflammatory demyelination" 6079: 6036: 5844: 5834: 5821: 5725: 5694: 5686: 5675: 5592: 3468:
Another commonly used measure that summarizes the total diffusivity is the
3299: 3053: 2361: 1544:
is a vector, there are 3 diffusion equations, one for each dimension. The
235:; trying to see which part of the brain is connected to which other part). 232: 186: 163: 116: 113: 77: 7628: 7620: 6605: 6534: 6491: 6122: 5987: 5820:
In some cases, the full set of tensor properties is of interest, but for
8944: 8499: 8331: 8321: 8301: 8291: 8233: 8228: 8197: 7394: 7355: 6940: 5776: 5698: 5678:, surgery is aided by knowing the proximity and relative position of the 5652: 3305: 3138: 3123: 3087: 2775: 201: 167: 7440: 6009:
Wedeen VJ, Hagmann P, Tseng WY, Reese TG, Weisskoff RM (December 2005).
3733:{\displaystyle \mathrm {MD} =(\lambda _{1}+\lambda _{2}+\lambda _{3})/3} 8580: 8343: 8338: 8306: 8062: 6252: 5839: 5794: 5596: 5489: in this section. Unsourced material may be challenged and removed. 4991:
Each measure lies between 0 and 1 and they sum to unity. An additional
3098: 1099: 190: 8102: 8085: 7934: 7917: 7857: 7840: 7110: 7014:
Basser PJ, Pajevic S, Pierpaoli C, Duda J, Aldroubi A (October 2000).
6983: 6826: 6728: 6711: 6569: 6408: 6027: 6010: 5618: 2396:
The following matrix displays the components of the diffusion tensor:
8907: 8843: 8296: 5630:
DTI of a healthy human brachial plexus. Taken from Wade et al., 2020.
5608: 3111: 3107: 2771: 85: 8046: 7897:. Proceedings of the 7th Annual Meeting of the ISMRM. Philadelphia. 5863:
Several full mathematical treatments of general tensors exist, e.g.
5464: 4502:{\displaystyle \lambda _{1}\geq \lambda _{2}\geq \lambda _{3}\geq 0} 8930: 8047:"Uber eine geometrische Anwendung der Abelschen Integralgleichnung" 7080:
Comptes Rendus Hebdomadaires des Séances de l'Académie des Sciences
7033:
10.1002/1522-2594(200010)44:4<625::AID-MRM17>3.0.CO;2-O
5714: 5580: 3074:) components have numbers in them but the off-diagonal components ( 1016: 8153: 7159: 4891:{\displaystyle \lambda _{1}\simeq \lambda _{2}\simeq \lambda _{3}} 1512:
which has terms for precession, T2 relaxation, and T1 relaxation.
8959: 8362: 7211:
Geometrical diffusion measures for MRI from tensor basis analysis
7209:
Westin CF, Peled S, Gudbjartsson H, Kikinis R, Jolesz FA (1997).
5825:
aligned with the main axon direction to accomplish tractography.
5721: 2755: 93: 7605: 6710:
Jensen JH, Helpern JA, Ramani A, Lu H, Kaczynski K (June 2005).
3427:{\displaystyle \lambda _{\perp }=(\lambda _{2}+\lambda _{3})/2.} 2781:
As it turns out, three more components can be added as follows:
8954: 6691:. Proceedings, 12th ISMRM Annual Meeting. Kyoto. p. 1238. 5663: 5644: 5604: 4722:{\displaystyle \lambda _{1}\simeq \lambda _{2}\gg \lambda _{3}} 4562:{\displaystyle \lambda _{1}\gg \lambda _{2}\simeq \lambda _{3}} 3311: 2386: 224: 216: 7208: 6960: 6469: 6100: 5717:. Applications in brain research include the investigation of 3340:
is an actual measurement of the ellipsoid we have calculated.
8981: 8192: 5702: 5671: 5640: 212: 182: 132: 7891:
High angular resolution diffusion imaging of the human brain
7887: 4995:
can used to describe the deviation from the spherical case:
3052:
components of each of them. Those three vectors are called "
1015:
gives a relationship between the flux and the concentration
39: 5600: 4110:
so that FA has a maximum value of 1. The whole formula for
3150: 3027:
are along the diagonal (red subscripts), but the variables
148: 8148: 7139: 7013: 6885:
An H, Ford AL, Vo K, Powers WJ, Lee JM, Lin W (May 2011).
6759:
Torrey HC (1956). "Bloch Equations with Diffusion Terms".
6057: 5797:
and vector mathematics developed nearly 100 years ago—the
5622:
Tractographic reconstruction of neural connections via DTI
5159:
There are other metrics of anisotropy used, including the
3126:
of an MRI voxel into a numerical measure of diffusion—the
2909:
still describe ellipsoids, but the additional components (
1098:
relates the time derivative of the concentration with the
7713: 7307: 7096: 5529:, the latter can be quantified by DWI and perfusion MRI. 3315:. The long one pointing along the axon direction will be 3093: 476:
is the signal intensity without the diffusion weighting,
248: 3133:. When various barriers and restricting factors such as 681:{\displaystyle {\frac {S(TE)}{S_{0}}}=\exp(-b\cdot ADC)} 7888:
Tuch DS, Weisskoff RM, Belliveau JW, Wedeen VJ (1999).
7664: 7223: 6008: 5693:, through which the motor information transit from the 5599:
of the tracts can be measured. The architecture of the
952:{\displaystyle \mathrm {ADC} (x,y,z)=\ln/(b_{1}-b_{2})} 27:
Method of utilizing water in magnetic resonance imaging
7915: 7770: 7258: 6627:
KÀrger, Jörg; Pfeifer, Harry; Heink, Wilfried (1988).
5525:
detecting both the infarcted core and the salvageable
4360: 2426: 1960:
then the Bloch-Torrey equation will have the solution
1886: 151:
trajectories than other diffusion imaging approaches.
7716:"Diffusion tensor imaging in cubital tunnel syndrome" 7259:
Alexander AL, Lee JE, Lazar M, Field AS (July 2007).
7140:
Richards TL, Heide AC, Tsuruda JS, Alvord EC (1992).
6709: 5685:
Diffusion tensor imaging data can be used to perform
5369: 5172: 5004: 4907: 4851: 4738: 4682: 4578: 4522: 4456: 4123: 4084: 3992: 3972: 3759: 3668: 3631: 3604: 3577: 3557: 3481: 3444: 3373: 3188: 3003: 2973: 2943: 2787: 2692: 2405: 2280: 2253: 2226: 2196: 2118: 2091: 1969: 1838: 1803: 1559: 1530: 1310: 1203: 1111: 1028: 997: 977: 800: 770: 743: 717: 697: 613: 586: 566: 546: 526: 502: 482: 455: 323: 289: 262: 8083: 7554: 7494: 6686: 5922: 711:, is replaced by an apparent diffusion coefficient, 181:(DTI) is important when a tissue—such as the neural 6512: 6333: 3350:is also called the longitudinal diffusivity or the 3279:{\displaystyle (ADC_{x}+ADC_{y}+ADC_{z})/3=ADC_{i}} 6626: 6390: 6184: 5443: 5345: 5148: 4980: 4890: 4830: 4721: 4661: 4561: 4509:, then the measures can be calculated as follows: 4501: 4435: 4343: 4102: 3998: 3978: 3955: 3732: 3644: 3617: 3590: 3563: 3540: 3457: 3426: 3278: 3019: 2989: 2959: 2878:{\displaystyle ax^{2}+by^{2}+cz^{2}+dyz+ezx+fxy=1} 2877: 2746: 2582: 2374: 2293: 2266: 2239: 2212: 2179: 2097: 2071: 1949: 1818: 1786: 1536: 1501: 1278: 1179: 1079: 1003: 983: 951: 783: 756: 729: 703: 680: 592: 572: 552: 532: 508: 488: 468: 438: 302: 275: 7834: 7832: 6135: 3309:. The lengths are symbolized by the Greek letter 1294:With no diffusion present, the change in nuclear 580:is the time between the two pulses, and finally, 439:{\displaystyle {\frac {S(TE)}{S_{0}}}=\exp \left} 9091: 6659: 2082:The exponential term will be referred to as the 143:rates. A variant of diffusion weighted imaging, 6792: 6790: 5666:such as trauma and in defining the severity of 5591:The principal application is in the imaging of 7829: 7348: 7301: 7016:"In vivo fiber tractography using DT-MRI data" 6884: 6547: 6442: 6241:Annals of Clinical and Translational Neurology 5893: 5541:DWI showing necrosis (shown as brighter) in a 2924:When the ellipsoid/tensor is represented by a 2180:{\displaystyle A=e^{-\sum _{i,j}b_{ij}D_{ij}}} 8169: 7991: 6438: 6436: 6283: 6234: 5957: 5889: 5887: 2347:DWI is a result of its partial T2 weighting. 194:direction from which an observer is looking. 158:, where it is a serious candidate to replace 66:Diffusion-weighted magnetic resonance imaging 7461: 7217: 7213:. ISMRM '97. Vancouver Canada. p. 1742. 7133: 7077: 6843: 6787: 5662:Tract-specific localization of white matter 3472:—which is the sum of the three eigenvalues, 2681: 131:(DWI), the intensity of each image element ( 6680: 3655:If we divide this sum by three we have the 2350: 84:in MR images. It allows the mapping of the 8176: 8162: 7426: 6878: 6433: 6094: 5884: 3343:The diffusivity along the principal axis, 3115:of diffusion in each voxel of the tissue. 3102:Visualization of DTI data with ellipsoids. 2340:smaller magnitude of diffusion as darker. 1080:{\displaystyle J(x,t)=-D\nabla \rho (x,t)} 38: 8101: 8013: 7933: 7856: 7812: 7747: 7690: 7582: 7572: 7550: 7548: 7528: 7403: 7393: 7325: 7284: 7185: 7031: 6982: 6910: 6827:"MRI Physics: Diffusion-Weighted Imaging" 6820: 6818: 6727: 6416: 6367: 6310: 6260: 6211: 6161: 6026: 5896:Comptes Rendus de l'AcadĂ©mie des Sciences 5813:For DTI, it is generally possible to use 5747:) from traumatically injured nerve roots. 5505:Learn how and when to remove this message 4429: 3322:and the two small axes will have lengths 1289: 9012:Orthogonal polarization spectral imaging 7369: 6936:"Diffusion weighted MRI in acute stroke" 6849: 6687:Chabert S, Mecca CC, Le Bihan D (2004). 5647:(i.e. a symmetric positive definite 3×3 5625: 5617: 3153:, and slower perpendicularly across it. 3097: 2318: 1094:. Then, given conservation of mass, the 7466:. Medical Radiology. pp. 227–252. 7261:"Diffusion tensor imaging of the brain" 2109:(ADC). In general, the attenuation is: 540:is the strength of the gradient pulse, 88:process of molecules, mainly water, in 14: 9092: 7545: 7429:AJR. American Journal of Roentgenology 7375: 7349:Weerakkody Y, Gaillard F, et al. 6815: 6796: 6758: 5579:Another application area of DWI is in 3571:is a diagonal matrix with eigenvalues 3094:Measures of anisotropy and diffusivity 2770:determine if the quadric describes an 2747:{\displaystyle ax^{2}+by^{2}+cz^{2}=1} 2220:terms incorporate the gradient fields 8157: 7314:Diagnostic and Interventional Imaging 7099:Journal of Magnetic Resonance Imaging 5595:where the location, orientation, and 1190:Putting the two together, we get the 8044: 7964: 7838: 7649: 7310:"Perfusion imaging in brain disease" 5850: 5732:Applications for peripheral nerves: 5487:adding citations to reliable sources 5458: 3086:) are 0. The second matrix provides 1298:over time is given by the classical 112:), has been used extensively to map 8183: 7054: 2597: 24: 8819:Sestamibi parathyroid scintigraphy 7671:Clinical and Translational Imaging 7178:10.1212/01.wnl.0000340982.01727.6e 6975:10.1097/01.rli.0000264059.46444.bf 6824: 6637:10.1016/b978-0-12-025512-2.50004-x 5416: 5374: 5371: 5325: 5291: 5247: 5203: 5177: 5174: 4361: 4248: 4204: 4160: 4128: 4125: 3986:is the matrix of eigenvectors and 3902: 3899: 3861: 3851: 3848: 3823: 3800: 3797: 3775: 3768: 3765: 3673: 3670: 3558: 3493: 3486: 3483: 3303:and the measures of their lengths 1769: 1751: 1246: 1230: 1207: 1153: 1138: 1115: 1056: 966: 808: 805: 802: 567: 407: 25: 9126: 8137: 6933: 3458:{\displaystyle \lambda _{\perp }} 3354:or even the parallel diffusivity 2562: 2498: 2434: 691:Also, the diffusion coefficient, 496:is the signal with the gradient, 9074: 9073: 6072:10.1016/j.neuroimage.2008.03.036 5564: 5549: 5534: 5463: 2758:surface. The relative values of 791:, of the b factor according to: 198:Diffusion Basis Spectrum Imaging 8576:Cholangiopancreatography (MRCP) 8077: 8038: 7985: 7958: 7909: 7881: 7764: 7707: 7658: 7643: 7599: 7488: 7455: 7420: 7342: 7252: 7202: 7153: 7090: 7071: 7048: 7007: 6954: 6927: 6752: 6703: 6653: 6620: 6576: 6550:The Journal of Chemical Physics 6541: 6527:10.1148/radiology.188.3.8351339 6506: 6463: 6384: 6327: 6277: 6115:10.1148/radiology.161.2.3763909 5960:Physics in Medicine and Biology 5857: 5603:in parallel bundles, and their 5474:needs additional citations for 5454: 3118:In an isotropic medium such as 2375:Mathematical foundation—tensors 122: 8824:Radioactive iodine uptake test 8090:Magnetic Resonance in Medicine 7922:Magnetic Resonance in Medicine 7845:Magnetic Resonance in Medicine 7020:Magnetic Resonance in Medicine 6716:Magnetic Resonance in Medicine 6586:Magnetic Resonance in Medicine 6472:Magnetic Resonance in Medicine 6228: 6178: 6129: 6051: 6015:Magnetic Resonance in Medicine 6002: 5951: 5916: 5668:diffuse traumatic brain injury 5429: 5422: 5337: 5331: 5307: 5303: 5297: 5275: 5263: 5259: 5253: 5231: 5219: 5215: 5209: 5187: 4784: 4758: 4418: 4379: 4373: 4367: 4335: 4281: 4273: 4264: 4260: 4254: 4232: 4220: 4216: 4210: 4188: 4176: 4172: 4166: 4144: 4141: 3912: 3906: 3877: 3855: 3826: 3804: 3778: 3772: 3719: 3680: 3496: 3490: 3413: 3387: 3246: 3189: 2412: 2329:apparent diffusion coefficient 2107:apparent diffusion coefficient 1866: 1845: 1810: 1778: 1763: 1729: 1720: 1694: 1669: 1644: 1616: 1601: 1572: 1519:mathematically showed how the 1480: 1471: 1445: 1420: 1395: 1367: 1352: 1323: 1270: 1258: 1225: 1213: 1174: 1162: 1133: 1121: 1074: 1062: 1044: 1032: 946: 920: 912: 909: 891: 873: 855: 842: 830: 812: 675: 654: 629: 620: 600:is the diffusion-coefficient. 560:is the duration of the pulse, 339: 330: 13: 1: 8804:Radionuclide ventriculography 8278:Lower gastrointestinal series 8270:Upper gastrointestinal series 7464:Diffusion-Weighted MR Imaging 7238:10.1016/s1361-8415(02)00053-1 6303:10.1158/1078-0432.ccr-20-0736 5925:Journal of Magnetic Resonance 5878: 4103:{\displaystyle 1/{\sqrt {2}}} 1826:is now the diffusion tensor. 8995:Optical coherence tomography 8917:Myocardial perfusion imaging 8505:Dental panoramic radiography 8024:10.1016/j.sigpro.2006.02.050 7472:10.1007/978-3-540-78576-7_14 7376:Chen F, Ni YC (March 2012). 7055:Nye, John Frederick (1957). 6903:10.1161/STROKEAHA.110.610501 5945:10.1016/0022-2364(85)90111-8 3645:{\displaystyle \lambda _{3}} 3618:{\displaystyle \lambda _{2}} 3591:{\displaystyle \lambda _{1}} 2754:. This equation describes a 2314: 2304: 242: 160:positron emission tomography 7: 6674:10.1560/HB5H-6XBR-1AW1-LNX9 6662:Israel Journal of Chemistry 5828: 5766: 5658:Applications in the brain: 10: 9131: 9115:Magnetic resonance imaging 8799:Ventilation/perfusion scan 8274:Small-bowel follow-through 7797:10.1038/s41598-021-00353-z 7732:10.1038/s41598-021-94211-7 7683:10.1007/s40336-020-00393-x 7521:10.1038/s41598-019-47195-4 7382:World Journal of Radiology 7327:10.1016/j.diii.2013.06.009 7277:10.1016/j.nurt.2007.05.011 6360:10.1038/s41598-021-84252-3 6192:Multiple Sclerosis Journal 5980:10.1088/0031-9155/30/4/009 5808: 2378: 1819:{\displaystyle {\vec {D}}} 156:non-small-cell lung cancer 145:diffusion spectrum imaging 129:diffusion weighted imaging 9069: 9048: 9040:Dynamic angiothermography 9020: 8976: 8925: 8902: 8892: 8857: 8784: 8774: 8765: 8708:Abdominal ultrasonography 8616: 8532: 8492: 8411: 8370: 8361: 8214: 8205: 8191: 8144:PNRC: About Diffusion MRI 7979:10.1093/biomet/50.3-4.353 7839:Tuch DS (December 2004). 6204:10.1177/13524585211023345 2682:Mathematics of ellipsoids 2671:Henri Hureau de SĂ©narmont 76:) is the use of specific 49: 37: 32: 9030:Non-contact thermography 8809:Radionuclide angiography 8661:Doppler echocardiography 7574:10.3389/fsurg.2020.00019 6291:Clinical Cancer Research 5607:sheaths, facilitate the 3564:{\displaystyle \Lambda } 2351:Diffusion tensor imaging 971:Given the concentration 247:Diffusion imaging is an 179:Diffusion tensor imaging 106:diffusion tensor imaging 8814:Radioisotope renography 6963:Investigative Radiology 6864:10.1148/radiol.13130420 6781:10.1103/PhysRev.104.563 6457:10.4304/jcp.6.4.825-829 5751:Cubital Tunnel Syndrome 5558:Wernicke encephalopathy 2885:. Many combinations of 573:{\displaystyle \Delta } 553:{\displaystyle \delta } 509:{\displaystyle \gamma } 8849:Gastric emptying study 7226:Medical Image Analysis 6799:"Restricted Diffusion" 6598:10.1002/mrm.1910360607 6484:10.1002/mrm.1910320605 5761:carpal tunnel syndrome 5757:Carpal Tunnel Syndrome 5670:. The localization of 5631: 5623: 5445: 5347: 5150: 4982: 4892: 4832: 4723: 4663: 4563: 4503: 4437: 4345: 4104: 4000: 3980: 3957: 3734: 3646: 3619: 3592: 3565: 3542: 3459: 3428: 3280: 3103: 3021: 3020:{\displaystyle cz^{2}} 2991: 2990:{\displaystyle by^{2}} 2961: 2960:{\displaystyle ax^{2}} 2879: 2748: 2584: 2381:Principal axis theorem 2324: 2295: 2268: 2241: 2214: 2213:{\displaystyle b_{ij}} 2181: 2099: 2073: 1951: 1820: 1788: 1538: 1503: 1290:Magnetization dynamics 1280: 1181: 1081: 1005: 985: 953: 785: 758: 731: 705: 682: 594: 574: 554: 534: 510: 490: 470: 440: 304: 277: 8510:X-ray motion analysis 8393:X-ray microtomography 8312:Hysterosalpingography 8219:Pneumoencephalography 7621:10.1002/ana.410420617 5629: 5621: 5613:anisotropic diffusion 5446: 5348: 5151: 4983: 4893: 4833: 4724: 4664: 4564: 4504: 4438: 4346: 4105: 4070:fractional anisotropy 4001: 3981: 3958: 3735: 3647: 3620: 3593: 3566: 3543: 3460: 3429: 3281: 3128:diffusion coefficient 3101: 3022: 2992: 2962: 2880: 2749: 2585: 2322: 2296: 2294:{\displaystyle G_{z}} 2269: 2267:{\displaystyle G_{y}} 2242: 2240:{\displaystyle G_{x}} 2215: 2182: 2100: 2074: 1952: 1821: 1789: 1547:Bloch-Torrey equation 1539: 1504: 1281: 1182: 1092:diffusion coefficient 1082: 1006: 986: 984:{\displaystyle \rho } 954: 786: 784:{\displaystyle b_{2}} 759: 757:{\displaystyle b_{1}} 732: 706: 683: 595: 575: 555: 535: 511: 491: 471: 469:{\displaystyle S_{0}} 441: 305: 303:{\displaystyle T_{2}} 278: 276:{\displaystyle T_{1}} 229:fractional anisotropy 9035:Contact thermography 8745:Emergency ultrasound 8683:Transcranial Doppler 8434:Abdominal and pelvis 7561:Frontiers in Surgery 7395:10.4329/wjr.v4.i3.63 6445:Journal of Computers 6154:10.1093/brain/awr307 6148:(Pt 12): 3590–3601. 5799:Funk Radon Transform 5713:from other types of 5483:improve this article 5367: 5170: 5002: 4905: 4849: 4736: 4680: 4576: 4520: 4454: 4358: 4121: 4082: 3990: 3970: 3757: 3666: 3629: 3602: 3575: 3555: 3479: 3442: 3371: 3186: 3001: 2971: 2941: 2785: 2690: 2403: 2278: 2251: 2224: 2194: 2116: 2089: 1967: 1836: 1801: 1557: 1528: 1308: 1201: 1109: 1026: 995: 975: 798: 768: 741: 715: 695: 611: 584: 564: 544: 524: 500: 480: 453: 321: 287: 260: 9002:Confocal microscopy 8880:Indium-111 WBC scan 8703:Echoencephalography 8439:Virtual colonoscopy 8006:2007SigPr..87..220B 7789:2021NatSR..1120935R 7609:Annals of Neurology 7513:2019NatSR...910742D 7441:10.2214/AJR.06.1403 7059:. Clarendon Press. 6773:1956PhRv..104..563T 6562:1965JChPh..42..288S 6352:2021NatSR..11.4749Y 5972:1985PMB....30..345T 5937:1985JMagR..64..479M 5711:Alzheimer's disease 5701:and the peripheral 5691:corticospinal tract 5680:corticospinal tract 5543:cerebral infarction 5519:cerebral infarction 5161:relative anisotropy 4334: 4316: 4298: 3120:cerebrospinal fluid 2344:Cerebral infarction 2331:(ADC) image, or an 1096:continuity equation 730:{\displaystyle ADC} 8990:Optical tomography 8839:Dacryoscintigraphy 8834:Immunoscintigraphy 8473:Whole body imaging 8224:Dental radiography 8149:White Matter Atlas 8063:10.1007/BF01456824 7777:Scientific Reports 7720:Scientific Reports 7501:Scientific Reports 7351:"Ischaemic stroke" 6797:Elster AD (2021). 6340:Scientific Reports 6253:10.1002/acn3.51037 5632: 5624: 5441: 5343: 5146: 4993:anisotropy measure 4978: 4888: 4828: 4719: 4659: 4559: 4499: 4433: 4341: 4320: 4302: 4284: 4100: 3996: 3976: 3953: 3951: 3730: 3642: 3615: 3588: 3561: 3538: 3455: 3424: 3363:radial diffusivity 3276: 3104: 3017: 2987: 2957: 2875: 2744: 2580: 2574: 2569: 2505: 2441: 2325: 2291: 2264: 2237: 2210: 2177: 2148: 2095: 2069: 1947: 1938: 1816: 1784: 1534: 1499: 1276: 1192:diffusion equation 1177: 1077: 1001: 981: 949: 781: 754: 727: 701: 678: 590: 570: 550: 530: 518:gyromagnetic ratio 506: 486: 466: 436: 300: 273: 206:multiple sclerosis 90:biological tissues 9087: 9086: 9049:Target conditions 8972: 8971: 8968: 8967: 8888: 8887: 8829:Bone scintigraphy 8794:Scintimammography 8789:Cholescintigraphy 8634:contrast-enhanced 8528: 8527: 8488: 8487: 8478:Full-body CT scan 8378:General operation 8357: 8356: 8327:Angiocardiography 8103:10.1002/mrm.29881 7994:Signal Processing 7935:10.1002/mrm.10268 7858:10.1002/mrm.20279 7481:978-3-540-78575-0 7320:(12): 1241–1257. 7265:Neurotherapeutics 7172:(16): 1378–1384. 7111:10.1002/jmri.1076 6803:mriquestions.com/ 6729:10.1002/mrm.20508 6646:978-0-12-025512-2 6570:10.1063/1.1695690 6409:10.1002/oby.23201 6297:(20): 5388–5399. 6028:10.1002/mrm.20642 5902:(15): 1109–1112. 5851:Explanatory notes 5515: 5514: 5507: 5439: 5341: 5323: 5316: 5144: 4976: 4826: 4657: 4339: 4338: 4276: 4114:looks like this: 4098: 3999:{\displaystyle D} 3979:{\displaystyle V} 3652:on its diagonal. 3352:axial diffusivity 2415: 2133: 2098:{\displaystyle A} 2006: 1987: 1869: 1848: 1813: 1781: 1766: 1746: 1732: 1686: 1672: 1647: 1619: 1604: 1587: 1575: 1537:{\displaystyle M} 1497: 1483: 1437: 1423: 1398: 1370: 1355: 1338: 1326: 1237: 1145: 1004:{\displaystyle J} 704:{\displaystyle D} 643: 593:{\displaystyle D} 533:{\displaystyle G} 489:{\displaystyle S} 421: 353: 63: 62: 18:Diffusion imaging 16:(Redirected from 9122: 9077: 9076: 8900: 8899: 8782: 8781: 8772: 8771: 8656:Echocardiography 8515:Hounsfield scale 8368: 8367: 8287:Cholecystography 8212: 8211: 8203: 8202: 8178: 8171: 8164: 8155: 8154: 8132: 8131: 8105: 8081: 8075: 8074: 8042: 8036: 8035: 8017: 7989: 7983: 7982: 7973:(3–4): 353–373. 7962: 7956: 7955: 7937: 7913: 7907: 7906: 7896: 7885: 7879: 7878: 7860: 7851:(6): 1358–1372. 7841:"Q-ball imaging" 7836: 7827: 7826: 7816: 7768: 7762: 7761: 7751: 7711: 7705: 7704: 7694: 7662: 7656: 7655: 7647: 7641: 7640: 7603: 7597: 7596: 7586: 7576: 7552: 7543: 7542: 7532: 7492: 7486: 7485: 7459: 7453: 7452: 7435:(6): 1622–1635. 7424: 7418: 7417: 7407: 7397: 7373: 7367: 7366: 7364: 7363: 7346: 7340: 7339: 7329: 7305: 7299: 7298: 7288: 7256: 7250: 7249: 7221: 7215: 7214: 7206: 7200: 7199: 7189: 7157: 7151: 7150: 7148: 7137: 7131: 7130: 7094: 7088: 7087: 7075: 7069: 7068: 7052: 7046: 7045: 7035: 7011: 7005: 7004: 6986: 6958: 6952: 6951: 6949: 6948: 6931: 6925: 6924: 6914: 6897:(5): 1276–1281. 6882: 6876: 6875: 6847: 6841: 6840: 6838: 6837: 6822: 6813: 6812: 6810: 6809: 6794: 6785: 6784: 6756: 6750: 6749: 6731: 6722:(6): 1432–1440. 6707: 6701: 6700: 6684: 6678: 6677: 6657: 6651: 6650: 6624: 6618: 6617: 6580: 6574: 6573: 6545: 6539: 6538: 6510: 6504: 6503: 6467: 6461: 6460: 6440: 6431: 6430: 6420: 6403:(8): 1328–1337. 6388: 6382: 6381: 6371: 6331: 6325: 6324: 6314: 6281: 6275: 6274: 6264: 6232: 6226: 6225: 6215: 6182: 6176: 6175: 6165: 6133: 6127: 6126: 6098: 6092: 6091: 6066:(4): 1267–1277. 6055: 6049: 6048: 6030: 6021:(6): 1377–1386. 6006: 6000: 5999: 5955: 5949: 5948: 5920: 5914: 5913: 5908: 5891: 5872: 5861: 5724:, as well as in 5568: 5553: 5538: 5510: 5503: 5499: 5496: 5490: 5467: 5459: 5450: 5448: 5447: 5442: 5440: 5438: 5437: 5436: 5414: 5413: 5412: 5403: 5402: 5393: 5392: 5382: 5377: 5352: 5350: 5349: 5344: 5342: 5340: 5324: 5319: 5315: 5314: 5287: 5286: 5271: 5270: 5243: 5242: 5227: 5226: 5199: 5198: 5186: 5185: 5180: 5155: 5153: 5152: 5147: 5145: 5143: 5142: 5141: 5129: 5128: 5116: 5115: 5105: 5104: 5103: 5088: 5087: 5075: 5074: 5064: 5059: 5058: 5040: 5039: 5027: 5026: 5014: 5013: 4987: 4985: 4984: 4979: 4977: 4975: 4974: 4973: 4961: 4960: 4948: 4947: 4937: 4936: 4935: 4922: 4917: 4916: 4897: 4895: 4894: 4889: 4887: 4886: 4874: 4873: 4861: 4860: 4837: 4835: 4834: 4829: 4827: 4825: 4824: 4823: 4811: 4810: 4798: 4797: 4787: 4783: 4782: 4770: 4769: 4753: 4748: 4747: 4728: 4726: 4725: 4720: 4718: 4717: 4705: 4704: 4692: 4691: 4668: 4666: 4665: 4660: 4658: 4656: 4655: 4654: 4642: 4641: 4629: 4628: 4618: 4617: 4616: 4604: 4603: 4593: 4588: 4587: 4568: 4566: 4565: 4560: 4558: 4557: 4545: 4544: 4532: 4531: 4508: 4506: 4505: 4500: 4492: 4491: 4479: 4478: 4466: 4465: 4442: 4440: 4439: 4434: 4425: 4417: 4416: 4404: 4403: 4391: 4390: 4350: 4348: 4347: 4342: 4340: 4333: 4328: 4315: 4310: 4297: 4292: 4277: 4272: 4271: 4244: 4243: 4228: 4227: 4200: 4199: 4184: 4183: 4156: 4155: 4137: 4136: 4131: 4109: 4107: 4106: 4101: 4099: 4094: 4092: 4009:prolate spheroid 4005: 4003: 4002: 3997: 3985: 3983: 3982: 3977: 3962: 3960: 3959: 3954: 3952: 3948: 3947: 3926: 3919: 3905: 3891: 3884: 3876: 3875: 3854: 3840: 3833: 3819: 3818: 3803: 3785: 3771: 3739: 3737: 3736: 3731: 3726: 3718: 3717: 3705: 3704: 3692: 3691: 3676: 3657:mean diffusivity 3651: 3649: 3648: 3643: 3641: 3640: 3624: 3622: 3621: 3616: 3614: 3613: 3597: 3595: 3594: 3589: 3587: 3586: 3570: 3568: 3567: 3562: 3547: 3545: 3544: 3539: 3537: 3536: 3524: 3523: 3511: 3510: 3489: 3464: 3462: 3461: 3456: 3454: 3453: 3433: 3431: 3430: 3425: 3420: 3412: 3411: 3399: 3398: 3383: 3382: 3285: 3283: 3282: 3277: 3275: 3274: 3253: 3245: 3244: 3226: 3225: 3207: 3206: 3026: 3024: 3023: 3018: 3016: 3015: 2996: 2994: 2993: 2988: 2986: 2985: 2966: 2964: 2963: 2958: 2956: 2955: 2884: 2882: 2881: 2876: 2832: 2831: 2816: 2815: 2800: 2799: 2753: 2751: 2750: 2745: 2737: 2736: 2721: 2720: 2705: 2704: 2598:Physical tensors 2589: 2587: 2586: 2581: 2579: 2578: 2571: 2570: 2554: 2553: 2539: 2538: 2522: 2521: 2507: 2506: 2490: 2489: 2473: 2472: 2458: 2457: 2443: 2442: 2417: 2416: 2408: 2391:symmetric matrix 2300: 2298: 2297: 2292: 2290: 2289: 2273: 2271: 2270: 2265: 2263: 2262: 2246: 2244: 2243: 2238: 2236: 2235: 2219: 2217: 2216: 2211: 2209: 2208: 2186: 2184: 2183: 2178: 2176: 2175: 2174: 2173: 2161: 2160: 2147: 2104: 2102: 2101: 2096: 2078: 2076: 2075: 2070: 2068: 2067: 2066: 2065: 2042: 2041: 2037: 2036: 2027: 2026: 2017: 2016: 2007: 1999: 1989: 1988: 1985: 1983: 1974: 1956: 1954: 1953: 1948: 1943: 1942: 1871: 1870: 1862: 1850: 1849: 1841: 1825: 1823: 1822: 1817: 1815: 1814: 1806: 1793: 1791: 1790: 1785: 1783: 1782: 1774: 1768: 1767: 1759: 1747: 1745: 1744: 1735: 1734: 1733: 1725: 1719: 1718: 1706: 1705: 1692: 1687: 1685: 1684: 1675: 1674: 1673: 1665: 1662: 1661: 1649: 1648: 1640: 1637: 1636: 1626: 1621: 1620: 1612: 1606: 1605: 1597: 1588: 1586: 1578: 1577: 1576: 1568: 1561: 1543: 1541: 1540: 1535: 1508: 1506: 1505: 1500: 1498: 1496: 1495: 1486: 1485: 1484: 1476: 1470: 1469: 1457: 1456: 1443: 1438: 1436: 1435: 1426: 1425: 1424: 1416: 1413: 1412: 1400: 1399: 1391: 1388: 1387: 1377: 1372: 1371: 1363: 1357: 1356: 1348: 1339: 1337: 1329: 1328: 1327: 1319: 1312: 1285: 1283: 1282: 1277: 1254: 1253: 1238: 1236: 1228: 1205: 1186: 1184: 1183: 1178: 1146: 1144: 1136: 1113: 1086: 1084: 1083: 1078: 1013:Fick's first law 1010: 1008: 1007: 1002: 990: 988: 987: 982: 958: 956: 955: 950: 945: 944: 932: 931: 919: 890: 889: 880: 854: 853: 811: 790: 788: 787: 782: 780: 779: 763: 761: 760: 755: 753: 752: 736: 734: 733: 728: 710: 708: 707: 702: 687: 685: 684: 679: 644: 642: 641: 632: 615: 599: 597: 596: 591: 579: 577: 576: 571: 559: 557: 556: 551: 539: 537: 536: 531: 515: 513: 512: 507: 495: 493: 492: 487: 475: 473: 472: 467: 465: 464: 445: 443: 442: 437: 435: 431: 427: 423: 422: 414: 401: 400: 391: 390: 381: 380: 354: 352: 351: 342: 325: 309: 307: 306: 301: 299: 298: 282: 280: 279: 274: 272: 271: 59: 42: 30: 29: 21: 9130: 9129: 9125: 9124: 9123: 9121: 9120: 9119: 9090: 9089: 9088: 9083: 9065: 9044: 9016: 8964: 8950:PET mammography 8921: 8884: 8870:Gallium-67 scan 8865:Octreotide scan 8853: 8761: 8612: 8524: 8484: 8407: 8388:High-resolution 8353: 8317:Skeletal survey 8283:Cholangiography 8196: 8187: 8185:Medical imaging 8182: 8140: 8135: 8082: 8078: 8045:Funk P (1919). 8043: 8039: 8015:10.1.1.104.9041 7990: 7986: 7963: 7959: 7914: 7910: 7894: 7886: 7882: 7837: 7830: 7769: 7765: 7712: 7708: 7663: 7659: 7650:Soll E (2015). 7648: 7644: 7604: 7600: 7553: 7546: 7493: 7489: 7482: 7460: 7456: 7425: 7421: 7374: 7370: 7361: 7359: 7347: 7343: 7306: 7302: 7257: 7253: 7222: 7218: 7207: 7203: 7158: 7154: 7146: 7138: 7134: 7095: 7091: 7076: 7072: 7053: 7049: 7012: 7008: 6959: 6955: 6946: 6944: 6932: 6928: 6883: 6879: 6848: 6844: 6835: 6833: 6823: 6816: 6807: 6805: 6795: 6788: 6761:Physical Review 6757: 6753: 6708: 6704: 6685: 6681: 6668:(1–2): 145–54. 6658: 6654: 6647: 6625: 6621: 6581: 6577: 6546: 6542: 6511: 6507: 6468: 6464: 6441: 6434: 6389: 6385: 6332: 6328: 6282: 6278: 6233: 6229: 6183: 6179: 6134: 6130: 6099: 6095: 6056: 6052: 6007: 6003: 5956: 5952: 5921: 5917: 5906: 5892: 5885: 5881: 5876: 5875: 5862: 5858: 5853: 5831: 5811: 5769: 5737:Brachial plexus 5719:neural networks 5575: 5569: 5560: 5554: 5545: 5539: 5511: 5500: 5494: 5491: 5480: 5468: 5457: 5432: 5428: 5415: 5408: 5404: 5398: 5394: 5388: 5384: 5383: 5381: 5370: 5368: 5365: 5364: 5318: 5317: 5310: 5306: 5282: 5278: 5266: 5262: 5238: 5234: 5222: 5218: 5194: 5190: 5184: 5173: 5171: 5168: 5167: 5137: 5133: 5124: 5120: 5111: 5107: 5106: 5099: 5095: 5083: 5079: 5070: 5066: 5065: 5063: 5054: 5050: 5035: 5031: 5022: 5018: 5009: 5005: 5003: 5000: 4999: 4969: 4965: 4956: 4952: 4943: 4939: 4938: 4931: 4927: 4923: 4921: 4912: 4908: 4906: 4903: 4902: 4882: 4878: 4869: 4865: 4856: 4852: 4850: 4847: 4846: 4819: 4815: 4806: 4802: 4793: 4789: 4788: 4778: 4774: 4765: 4761: 4754: 4752: 4743: 4739: 4737: 4734: 4733: 4713: 4709: 4700: 4696: 4687: 4683: 4681: 4678: 4677: 4650: 4646: 4637: 4633: 4624: 4620: 4619: 4612: 4608: 4599: 4595: 4594: 4592: 4583: 4579: 4577: 4574: 4573: 4553: 4549: 4540: 4536: 4527: 4523: 4521: 4518: 4517: 4487: 4483: 4474: 4470: 4461: 4457: 4455: 4452: 4451: 4448:oblate spheroid 4421: 4412: 4408: 4399: 4395: 4386: 4382: 4359: 4356: 4355: 4329: 4324: 4311: 4306: 4293: 4288: 4267: 4263: 4239: 4235: 4223: 4219: 4195: 4191: 4179: 4175: 4151: 4147: 4135: 4124: 4122: 4119: 4118: 4093: 4088: 4083: 4080: 4079: 4066: 4059: 4053:) + ( 4052: 4045: 4039:) + ( 4038: 4031: 4024: 4017: 3991: 3988: 3987: 3971: 3968: 3967: 3950: 3949: 3943: 3939: 3924: 3923: 3915: 3898: 3889: 3888: 3880: 3868: 3864: 3847: 3838: 3837: 3829: 3811: 3807: 3796: 3789: 3781: 3764: 3760: 3758: 3755: 3754: 3748: 3722: 3713: 3709: 3700: 3696: 3687: 3683: 3669: 3667: 3664: 3663: 3636: 3632: 3630: 3627: 3626: 3609: 3605: 3603: 3600: 3599: 3582: 3578: 3576: 3573: 3572: 3556: 3553: 3552: 3532: 3528: 3519: 3515: 3506: 3502: 3482: 3480: 3477: 3476: 3449: 3445: 3443: 3440: 3439: 3416: 3407: 3403: 3394: 3390: 3378: 3374: 3372: 3369: 3368: 3360: 3349: 3335: 3328: 3321: 3270: 3266: 3249: 3240: 3236: 3221: 3217: 3202: 3198: 3187: 3184: 3183: 3178: 3172: 3166: 3147:Brownian motion 3096: 3060:Diagonalization 3011: 3007: 3002: 2999: 2998: 2981: 2977: 2972: 2969: 2968: 2951: 2947: 2942: 2939: 2938: 2827: 2823: 2811: 2807: 2795: 2791: 2786: 2783: 2782: 2732: 2728: 2716: 2712: 2700: 2696: 2691: 2688: 2687: 2684: 2600: 2573: 2572: 2561: 2557: 2555: 2546: 2542: 2540: 2531: 2527: 2524: 2523: 2514: 2510: 2508: 2497: 2493: 2491: 2482: 2478: 2475: 2474: 2465: 2461: 2459: 2450: 2446: 2444: 2433: 2429: 2422: 2421: 2407: 2406: 2404: 2401: 2400: 2383: 2377: 2353: 2317: 2307: 2285: 2281: 2279: 2276: 2275: 2258: 2254: 2252: 2249: 2248: 2231: 2227: 2225: 2222: 2221: 2201: 2197: 2195: 2192: 2191: 2166: 2162: 2153: 2149: 2137: 2129: 2125: 2117: 2114: 2113: 2090: 2087: 2086: 2061: 2057: 2050: 2046: 2032: 2028: 2022: 2018: 2012: 2008: 1998: 1994: 1990: 1984: 1979: 1978: 1970: 1968: 1965: 1964: 1937: 1936: 1931: 1926: 1920: 1919: 1914: 1909: 1903: 1902: 1897: 1892: 1882: 1881: 1861: 1860: 1840: 1839: 1837: 1834: 1833: 1805: 1804: 1802: 1799: 1798: 1773: 1772: 1758: 1757: 1740: 1736: 1724: 1723: 1714: 1710: 1701: 1697: 1693: 1691: 1680: 1676: 1664: 1663: 1657: 1653: 1639: 1638: 1632: 1628: 1627: 1625: 1611: 1610: 1596: 1595: 1579: 1567: 1566: 1562: 1560: 1558: 1555: 1554: 1529: 1526: 1525: 1521:Bloch equations 1491: 1487: 1475: 1474: 1465: 1461: 1452: 1448: 1444: 1442: 1431: 1427: 1415: 1414: 1408: 1404: 1390: 1389: 1383: 1379: 1378: 1376: 1362: 1361: 1347: 1346: 1330: 1318: 1317: 1313: 1311: 1309: 1306: 1305: 1292: 1249: 1245: 1229: 1206: 1204: 1202: 1199: 1198: 1137: 1114: 1112: 1110: 1107: 1106: 1090:where D is the 1027: 1024: 1023: 996: 993: 992: 976: 973: 972: 969: 967:Diffusion model 940: 936: 927: 923: 915: 885: 881: 876: 849: 845: 801: 799: 796: 795: 775: 771: 769: 766: 765: 748: 744: 742: 739: 738: 716: 713: 712: 696: 693: 692: 637: 633: 616: 614: 612: 609: 608: 585: 582: 581: 565: 562: 561: 545: 542: 541: 525: 522: 521: 501: 498: 497: 481: 478: 477: 460: 456: 454: 451: 450: 413: 406: 402: 396: 392: 386: 382: 376: 372: 368: 364: 347: 343: 326: 324: 322: 319: 318: 294: 290: 288: 285: 284: 267: 263: 261: 258: 257: 245: 172:cerebral cortex 125: 55: 45: 28: 23: 22: 15: 12: 11: 5: 9128: 9118: 9117: 9112: 9107: 9102: 9085: 9084: 9082: 9081: 9070: 9067: 9066: 9064: 9063: 9058: 9052: 9050: 9046: 9045: 9043: 9042: 9037: 9032: 9026: 9024: 9018: 9017: 9015: 9014: 9009: 9007:Endomicroscopy 9004: 8999: 8998: 8997: 8986: 8984: 8974: 8973: 8970: 8969: 8966: 8965: 8963: 8962: 8957: 8952: 8947: 8942: 8936: 8934: 8923: 8922: 8920: 8919: 8913: 8911: 8897: 8890: 8889: 8886: 8885: 8883: 8882: 8877: 8872: 8867: 8861: 8859: 8855: 8854: 8852: 8851: 8846: 8841: 8836: 8831: 8826: 8821: 8816: 8811: 8806: 8801: 8796: 8791: 8785: 8779: 8769: 8763: 8762: 8760: 8759: 8758: 8757: 8752: 8742: 8737: 8732: 8727: 8722: 8721: 8720: 8715: 8705: 8700: 8695: 8690: 8685: 8680: 8679: 8678: 8673: 8668: 8663: 8653: 8652: 8651: 8646: 8641: 8636: 8631: 8622: 8620: 8614: 8613: 8611: 8610: 8605: 8604: 8603: 8598: 8593: 8583: 8578: 8573: 8568: 8567: 8566: 8556: 8551: 8550: 8549: 8538: 8536: 8530: 8529: 8526: 8525: 8523: 8522: 8517: 8512: 8507: 8502: 8496: 8494: 8490: 8489: 8486: 8485: 8483: 8482: 8481: 8480: 8470: 8465: 8460: 8459: 8458: 8453: 8443: 8442: 8441: 8431: 8430: 8429: 8424: 8415: 8413: 8409: 8408: 8406: 8405: 8400: 8395: 8390: 8385: 8380: 8374: 8372: 8365: 8359: 8358: 8355: 8354: 8352: 8351: 8346: 8341: 8336: 8335: 8334: 8329: 8319: 8314: 8309: 8304: 8299: 8294: 8289: 8280: 8267: 8258: 8253: 8248: 8247: 8246: 8236: 8231: 8226: 8221: 8215: 8209: 8200: 8189: 8188: 8181: 8180: 8173: 8166: 8158: 8152: 8151: 8146: 8139: 8138:External links 8136: 8134: 8133: 8096:(2): 773–783. 8076: 8037: 8000:(2): 220–236. 7984: 7957: 7928:(4): 577–582. 7908: 7880: 7828: 7763: 7706: 7677:(6): 419–431. 7657: 7642: 7615:(6): 951–962. 7598: 7544: 7487: 7480: 7454: 7419: 7368: 7341: 7300: 7271:(3): 316–329. 7251: 7216: 7201: 7152: 7132: 7105:(4): 534–546. 7089: 7070: 7047: 7026:(4): 625–632. 7006: 6969:(6): 412–419. 6953: 6926: 6877: 6842: 6814: 6786: 6767:(3): 563–565. 6751: 6702: 6679: 6652: 6645: 6619: 6592:(6): 847–857. 6575: 6556:(1): 288–292. 6540: 6521:(3): 719–725. 6505: 6478:(6): 707–713. 6462: 6451:(4): 825–829. 6432: 6383: 6326: 6276: 6247:(5): 695–706. 6227: 6198:(3): 418–428. 6177: 6128: 6109:(2): 401–407. 6093: 6050: 6001: 5966:(4): 345–349. 5950: 5931:(3): 479–486. 5915: 5882: 5880: 5877: 5874: 5873: 5869:component free 5855: 5854: 5852: 5849: 5848: 5847: 5842: 5837: 5830: 5827: 5815:linear algebra 5810: 5807: 5768: 5765: 5764: 5763: 5754: 5748: 5730: 5729: 5706: 5683: 5636:magnetic field 5577: 5576: 5573:MELAS syndrome 5570: 5563: 5561: 5555: 5548: 5546: 5540: 5533: 5513: 5512: 5471: 5469: 5462: 5456: 5453: 5452: 5451: 5435: 5431: 5427: 5424: 5421: 5418: 5411: 5407: 5401: 5397: 5391: 5387: 5380: 5376: 5373: 5354: 5353: 5339: 5336: 5333: 5330: 5327: 5322: 5313: 5309: 5305: 5302: 5299: 5296: 5293: 5290: 5285: 5281: 5277: 5274: 5269: 5265: 5261: 5258: 5255: 5252: 5249: 5246: 5241: 5237: 5233: 5230: 5225: 5221: 5217: 5214: 5211: 5208: 5205: 5202: 5197: 5193: 5189: 5183: 5179: 5176: 5157: 5156: 5140: 5136: 5132: 5127: 5123: 5119: 5114: 5110: 5102: 5098: 5094: 5091: 5086: 5082: 5078: 5073: 5069: 5062: 5057: 5053: 5049: 5046: 5043: 5038: 5034: 5030: 5025: 5021: 5017: 5012: 5008: 4989: 4988: 4972: 4968: 4964: 4959: 4955: 4951: 4946: 4942: 4934: 4930: 4926: 4920: 4915: 4911: 4885: 4881: 4877: 4872: 4868: 4864: 4859: 4855: 4843:spherical case 4839: 4838: 4822: 4818: 4814: 4809: 4805: 4801: 4796: 4792: 4786: 4781: 4777: 4773: 4768: 4764: 4760: 4757: 4751: 4746: 4742: 4716: 4712: 4708: 4703: 4699: 4695: 4690: 4686: 4670: 4669: 4653: 4649: 4645: 4640: 4636: 4632: 4627: 4623: 4615: 4611: 4607: 4602: 4598: 4591: 4586: 4582: 4556: 4552: 4548: 4543: 4539: 4535: 4530: 4526: 4498: 4495: 4490: 4486: 4482: 4477: 4473: 4469: 4464: 4460: 4432: 4428: 4424: 4420: 4415: 4411: 4407: 4402: 4398: 4394: 4389: 4385: 4381: 4378: 4375: 4372: 4369: 4366: 4363: 4352: 4351: 4337: 4332: 4327: 4323: 4319: 4314: 4309: 4305: 4301: 4296: 4291: 4287: 4283: 4280: 4275: 4270: 4266: 4262: 4259: 4256: 4253: 4250: 4247: 4242: 4238: 4234: 4231: 4226: 4222: 4218: 4215: 4212: 4209: 4206: 4203: 4198: 4194: 4190: 4187: 4182: 4178: 4174: 4171: 4168: 4165: 4162: 4159: 4154: 4150: 4146: 4143: 4140: 4134: 4130: 4127: 4097: 4091: 4087: 4064: 4057: 4050: 4043: 4036: 4029: 4022: 4015: 3995: 3975: 3964: 3963: 3946: 3942: 3938: 3935: 3932: 3929: 3927: 3925: 3922: 3918: 3914: 3911: 3908: 3904: 3901: 3897: 3894: 3892: 3890: 3887: 3883: 3879: 3874: 3871: 3867: 3863: 3860: 3857: 3853: 3850: 3846: 3843: 3841: 3839: 3836: 3832: 3828: 3825: 3822: 3817: 3814: 3810: 3806: 3802: 3799: 3795: 3792: 3790: 3788: 3784: 3780: 3777: 3774: 3770: 3767: 3763: 3762: 3746: 3741: 3740: 3729: 3725: 3721: 3716: 3712: 3708: 3703: 3699: 3695: 3690: 3686: 3682: 3679: 3675: 3672: 3639: 3635: 3612: 3608: 3585: 3581: 3560: 3549: 3548: 3535: 3531: 3527: 3522: 3518: 3514: 3509: 3505: 3501: 3498: 3495: 3492: 3488: 3485: 3452: 3448: 3435: 3434: 3423: 3419: 3415: 3410: 3406: 3402: 3397: 3393: 3389: 3386: 3381: 3377: 3358: 3347: 3333: 3326: 3319: 3287: 3286: 3273: 3269: 3265: 3262: 3259: 3256: 3252: 3248: 3243: 3239: 3235: 3232: 3229: 3224: 3220: 3216: 3213: 3210: 3205: 3201: 3197: 3194: 3191: 3174: 3168: 3162: 3135:cell membranes 3095: 3092: 3014: 3010: 3006: 2984: 2980: 2976: 2954: 2950: 2946: 2874: 2871: 2868: 2865: 2862: 2859: 2856: 2853: 2850: 2847: 2844: 2841: 2838: 2835: 2830: 2826: 2822: 2819: 2814: 2810: 2806: 2803: 2798: 2794: 2790: 2743: 2740: 2735: 2731: 2727: 2724: 2719: 2715: 2711: 2708: 2703: 2699: 2695: 2683: 2680: 2674:ellipsoid. As 2599: 2596: 2591: 2590: 2577: 2568: 2565: 2560: 2556: 2552: 2549: 2545: 2541: 2537: 2534: 2530: 2526: 2525: 2520: 2517: 2513: 2509: 2504: 2501: 2496: 2492: 2488: 2485: 2481: 2477: 2476: 2471: 2468: 2464: 2460: 2456: 2453: 2449: 2445: 2440: 2437: 2432: 2428: 2427: 2425: 2420: 2414: 2411: 2376: 2373: 2352: 2349: 2316: 2313: 2306: 2303: 2288: 2284: 2261: 2257: 2234: 2230: 2207: 2204: 2200: 2188: 2187: 2172: 2169: 2165: 2159: 2156: 2152: 2146: 2143: 2140: 2136: 2132: 2128: 2124: 2121: 2094: 2080: 2079: 2064: 2060: 2056: 2053: 2049: 2045: 2040: 2035: 2031: 2025: 2021: 2015: 2011: 2005: 2002: 1997: 1993: 1982: 1977: 1973: 1958: 1957: 1946: 1941: 1935: 1932: 1930: 1927: 1925: 1922: 1921: 1918: 1915: 1913: 1910: 1908: 1905: 1904: 1901: 1898: 1896: 1893: 1891: 1888: 1887: 1885: 1880: 1877: 1874: 1868: 1865: 1859: 1856: 1853: 1847: 1844: 1812: 1809: 1795: 1794: 1780: 1777: 1771: 1765: 1762: 1756: 1753: 1750: 1743: 1739: 1731: 1728: 1722: 1717: 1713: 1709: 1704: 1700: 1696: 1690: 1683: 1679: 1671: 1668: 1660: 1656: 1652: 1646: 1643: 1635: 1631: 1624: 1618: 1615: 1609: 1603: 1600: 1594: 1591: 1585: 1582: 1574: 1571: 1565: 1533: 1510: 1509: 1494: 1490: 1482: 1479: 1473: 1468: 1464: 1460: 1455: 1451: 1447: 1441: 1434: 1430: 1422: 1419: 1411: 1407: 1403: 1397: 1394: 1386: 1382: 1375: 1369: 1366: 1360: 1354: 1351: 1345: 1342: 1336: 1333: 1325: 1322: 1316: 1300:Bloch equation 1291: 1288: 1287: 1286: 1275: 1272: 1269: 1266: 1263: 1260: 1257: 1252: 1248: 1244: 1241: 1235: 1232: 1227: 1224: 1221: 1218: 1215: 1212: 1209: 1188: 1187: 1176: 1173: 1170: 1167: 1164: 1161: 1158: 1155: 1152: 1149: 1143: 1140: 1135: 1132: 1129: 1126: 1123: 1120: 1117: 1088: 1087: 1076: 1073: 1070: 1067: 1064: 1061: 1058: 1055: 1052: 1049: 1046: 1043: 1040: 1037: 1034: 1031: 1000: 980: 968: 965: 960: 959: 948: 943: 939: 935: 930: 926: 922: 918: 914: 911: 908: 905: 902: 899: 896: 893: 888: 884: 879: 875: 872: 869: 866: 863: 860: 857: 852: 848: 844: 841: 838: 835: 832: 829: 826: 823: 820: 817: 814: 810: 807: 804: 778: 774: 751: 747: 726: 723: 720: 700: 689: 688: 677: 674: 671: 668: 665: 662: 659: 656: 653: 650: 647: 640: 636: 631: 628: 625: 622: 619: 589: 569: 549: 529: 505: 485: 463: 459: 447: 446: 434: 430: 426: 420: 417: 412: 409: 405: 399: 395: 389: 385: 379: 375: 371: 367: 363: 360: 357: 350: 346: 341: 338: 335: 332: 329: 297: 293: 270: 266: 244: 241: 124: 121: 119:in the brain. 100:, fibers, and 98:macromolecules 61: 60: 53: 47: 46: 43: 35: 34: 26: 9: 6: 4: 3: 2: 9127: 9116: 9113: 9111: 9108: 9106: 9103: 9101: 9098: 9097: 9095: 9080: 9072: 9071: 9068: 9062: 9059: 9057: 9054: 9053: 9051: 9047: 9041: 9038: 9036: 9033: 9031: 9028: 9027: 9025: 9023: 9019: 9013: 9010: 9008: 9005: 9003: 9000: 8996: 8993: 8992: 8991: 8988: 8987: 8985: 8983: 8979: 8975: 8961: 8958: 8956: 8953: 8951: 8948: 8946: 8943: 8941: 8938: 8937: 8935: 8932: 8928: 8924: 8918: 8915: 8914: 8912: 8909: 8905: 8901: 8898: 8896: 8891: 8881: 8878: 8876: 8875:Ga-68-DOTATOC 8873: 8871: 8868: 8866: 8863: 8862: 8860: 8856: 8850: 8847: 8845: 8842: 8840: 8837: 8835: 8832: 8830: 8827: 8825: 8822: 8820: 8817: 8815: 8812: 8810: 8807: 8805: 8802: 8800: 8797: 8795: 8792: 8790: 8787: 8786: 8783: 8780: 8778: 8773: 8770: 8768: 8764: 8756: 8753: 8751: 8748: 8747: 8746: 8743: 8741: 8738: 8736: 8733: 8731: 8728: 8726: 8723: 8719: 8716: 8714: 8711: 8710: 8709: 8706: 8704: 8701: 8699: 8696: 8694: 8691: 8689: 8688:Intravascular 8686: 8684: 8681: 8677: 8674: 8672: 8669: 8667: 8664: 8662: 8659: 8658: 8657: 8654: 8650: 8647: 8645: 8642: 8640: 8637: 8635: 8632: 8630: 8627: 8626: 8624: 8623: 8621: 8619: 8615: 8609: 8608:Synthetic MRI 8606: 8602: 8599: 8597: 8594: 8592: 8589: 8588: 8587: 8584: 8582: 8579: 8577: 8574: 8572: 8569: 8565: 8562: 8561: 8560: 8557: 8555: 8552: 8548: 8545: 8544: 8543: 8540: 8539: 8537: 8535: 8531: 8521: 8518: 8516: 8513: 8511: 8508: 8506: 8503: 8501: 8498: 8497: 8495: 8491: 8479: 8476: 8475: 8474: 8471: 8469: 8466: 8464: 8461: 8457: 8454: 8452: 8449: 8448: 8447: 8444: 8440: 8437: 8436: 8435: 8432: 8428: 8425: 8423: 8420: 8419: 8417: 8416: 8414: 8410: 8404: 8401: 8399: 8398:Electron beam 8396: 8394: 8391: 8389: 8386: 8384: 8381: 8379: 8376: 8375: 8373: 8369: 8366: 8364: 8360: 8350: 8349:Orbital x-ray 8347: 8345: 8342: 8340: 8337: 8333: 8330: 8328: 8325: 8324: 8323: 8320: 8318: 8315: 8313: 8310: 8308: 8305: 8303: 8300: 8298: 8295: 8293: 8290: 8288: 8284: 8281: 8279: 8275: 8271: 8268: 8266: 8262: 8259: 8257: 8254: 8252: 8249: 8245: 8244:Bronchography 8242: 8241: 8240: 8237: 8235: 8232: 8230: 8227: 8225: 8222: 8220: 8217: 8216: 8213: 8210: 8208: 8204: 8201: 8199: 8194: 8190: 8186: 8179: 8174: 8172: 8167: 8165: 8160: 8159: 8156: 8150: 8147: 8145: 8142: 8141: 8129: 8125: 8121: 8117: 8113: 8109: 8104: 8099: 8095: 8091: 8087: 8080: 8072: 8068: 8064: 8060: 8056: 8052: 8048: 8041: 8033: 8029: 8025: 8021: 8016: 8011: 8007: 8003: 7999: 7995: 7988: 7980: 7976: 7972: 7968: 7961: 7953: 7949: 7945: 7941: 7936: 7931: 7927: 7923: 7919: 7912: 7904: 7900: 7893: 7892: 7884: 7876: 7872: 7868: 7864: 7859: 7854: 7850: 7846: 7842: 7835: 7833: 7824: 7820: 7815: 7810: 7806: 7802: 7798: 7794: 7790: 7786: 7782: 7778: 7774: 7767: 7759: 7755: 7750: 7745: 7741: 7737: 7733: 7729: 7725: 7721: 7717: 7710: 7702: 7698: 7693: 7688: 7684: 7680: 7676: 7672: 7668: 7661: 7653: 7646: 7638: 7634: 7630: 7626: 7622: 7618: 7614: 7610: 7602: 7594: 7590: 7585: 7580: 7575: 7570: 7566: 7562: 7558: 7551: 7549: 7540: 7536: 7531: 7526: 7522: 7518: 7514: 7510: 7506: 7502: 7498: 7491: 7483: 7477: 7473: 7469: 7465: 7458: 7450: 7446: 7442: 7438: 7434: 7430: 7423: 7415: 7411: 7406: 7401: 7396: 7391: 7387: 7383: 7379: 7372: 7358: 7357: 7352: 7345: 7337: 7333: 7328: 7323: 7319: 7315: 7311: 7304: 7296: 7292: 7287: 7282: 7278: 7274: 7270: 7266: 7262: 7255: 7247: 7243: 7239: 7235: 7232:(2): 93–108. 7231: 7227: 7220: 7212: 7205: 7197: 7193: 7188: 7183: 7179: 7175: 7171: 7167: 7163: 7156: 7145: 7144: 7136: 7128: 7124: 7120: 7116: 7112: 7108: 7104: 7100: 7093: 7085: 7082:(in French). 7081: 7074: 7066: 7062: 7058: 7051: 7043: 7039: 7034: 7029: 7025: 7021: 7017: 7010: 7002: 6998: 6994: 6990: 6985: 6980: 6976: 6972: 6968: 6964: 6957: 6943: 6942: 6937: 6930: 6922: 6918: 6913: 6908: 6904: 6900: 6896: 6892: 6888: 6881: 6873: 6869: 6865: 6861: 6858:(2): 318–22. 6857: 6853: 6846: 6832: 6828: 6821: 6819: 6804: 6800: 6793: 6791: 6782: 6778: 6774: 6770: 6766: 6762: 6755: 6747: 6743: 6739: 6735: 6730: 6725: 6721: 6717: 6713: 6706: 6698: 6694: 6690: 6683: 6675: 6671: 6667: 6663: 6656: 6648: 6642: 6638: 6634: 6630: 6623: 6615: 6611: 6607: 6603: 6599: 6595: 6591: 6587: 6579: 6571: 6567: 6563: 6559: 6555: 6551: 6544: 6536: 6532: 6528: 6524: 6520: 6516: 6509: 6501: 6497: 6493: 6489: 6485: 6481: 6477: 6473: 6466: 6458: 6454: 6450: 6446: 6439: 6437: 6428: 6424: 6419: 6414: 6410: 6406: 6402: 6398: 6394: 6387: 6379: 6375: 6370: 6365: 6361: 6357: 6353: 6349: 6345: 6341: 6337: 6330: 6322: 6318: 6313: 6308: 6304: 6300: 6296: 6292: 6288: 6280: 6272: 6268: 6263: 6258: 6254: 6250: 6246: 6242: 6238: 6231: 6223: 6219: 6214: 6209: 6205: 6201: 6197: 6193: 6189: 6181: 6173: 6169: 6164: 6159: 6155: 6151: 6147: 6143: 6139: 6132: 6124: 6120: 6116: 6112: 6108: 6104: 6097: 6089: 6085: 6081: 6077: 6073: 6069: 6065: 6061: 6054: 6046: 6042: 6038: 6034: 6029: 6024: 6020: 6016: 6012: 6005: 5997: 5993: 5989: 5985: 5981: 5977: 5973: 5969: 5965: 5961: 5954: 5946: 5942: 5938: 5934: 5930: 5926: 5919: 5911: 5905: 5901: 5898:(in French). 5897: 5890: 5888: 5883: 5870: 5866: 5860: 5856: 5846: 5843: 5841: 5838: 5836: 5833: 5832: 5826: 5823: 5818: 5816: 5806: 5802: 5800: 5796: 5790: 5787: 5786:tessellations 5783: 5778: 5773: 5762: 5758: 5755: 5752: 5749: 5746: 5742: 5738: 5735: 5734: 5733: 5727: 5723: 5720: 5716: 5712: 5707: 5704: 5700: 5696: 5692: 5688: 5684: 5681: 5677: 5673: 5669: 5665: 5661: 5660: 5659: 5656: 5654: 5650: 5646: 5642: 5637: 5628: 5620: 5616: 5614: 5610: 5606: 5602: 5598: 5594: 5589: 5586: 5582: 5574: 5567: 5562: 5559: 5552: 5547: 5544: 5537: 5532: 5531: 5530: 5528: 5524: 5523:perfusion MRI 5520: 5509: 5506: 5498: 5495:December 2013 5488: 5484: 5478: 5477: 5472:This section 5470: 5466: 5461: 5460: 5433: 5425: 5419: 5409: 5405: 5399: 5395: 5389: 5385: 5378: 5363: 5362: 5361: 5359: 5334: 5328: 5320: 5311: 5300: 5294: 5288: 5283: 5279: 5272: 5267: 5256: 5250: 5244: 5239: 5235: 5228: 5223: 5212: 5206: 5200: 5195: 5191: 5181: 5166: 5165: 5164: 5162: 5138: 5134: 5130: 5125: 5121: 5117: 5112: 5108: 5100: 5096: 5092: 5089: 5084: 5080: 5076: 5071: 5067: 5060: 5055: 5051: 5047: 5044: 5041: 5036: 5032: 5028: 5023: 5019: 5015: 5010: 5006: 4998: 4997: 4996: 4994: 4970: 4966: 4962: 4957: 4953: 4949: 4944: 4940: 4932: 4928: 4924: 4918: 4913: 4909: 4901: 4900: 4899: 4883: 4879: 4875: 4870: 4866: 4862: 4857: 4853: 4844: 4820: 4816: 4812: 4807: 4803: 4799: 4794: 4790: 4779: 4775: 4771: 4766: 4762: 4755: 4749: 4744: 4740: 4732: 4731: 4730: 4714: 4710: 4706: 4701: 4697: 4693: 4688: 4684: 4675: 4651: 4647: 4643: 4638: 4634: 4630: 4625: 4621: 4613: 4609: 4605: 4600: 4596: 4589: 4584: 4580: 4572: 4571: 4570: 4554: 4550: 4546: 4541: 4537: 4533: 4528: 4524: 4515: 4510: 4496: 4493: 4488: 4484: 4480: 4475: 4471: 4467: 4462: 4458: 4449: 4443: 4430: 4426: 4422: 4413: 4409: 4405: 4400: 4396: 4392: 4387: 4383: 4376: 4370: 4364: 4330: 4325: 4321: 4317: 4312: 4307: 4303: 4299: 4294: 4289: 4285: 4278: 4268: 4257: 4251: 4245: 4240: 4236: 4229: 4224: 4213: 4207: 4201: 4196: 4192: 4185: 4180: 4169: 4163: 4157: 4152: 4148: 4138: 4132: 4117: 4116: 4115: 4113: 4095: 4089: 4085: 4076: 4072: 4071: 4063: 4060: âˆ’  4056: 4049: 4046: âˆ’  4042: 4035: 4032: âˆ’  4028: 4021: 4014: 4010: 3993: 3973: 3944: 3940: 3936: 3933: 3930: 3928: 3920: 3916: 3909: 3895: 3893: 3885: 3881: 3872: 3869: 3865: 3858: 3844: 3842: 3834: 3830: 3820: 3815: 3812: 3808: 3793: 3791: 3786: 3782: 3753: 3752: 3751: 3749: 3743:which equals 3727: 3723: 3714: 3710: 3706: 3701: 3697: 3693: 3688: 3684: 3677: 3662: 3661: 3660: 3658: 3653: 3637: 3633: 3610: 3606: 3583: 3579: 3533: 3529: 3525: 3520: 3516: 3512: 3507: 3503: 3499: 3475: 3474: 3473: 3471: 3466: 3450: 3446: 3421: 3417: 3408: 3404: 3400: 3395: 3391: 3384: 3379: 3375: 3367: 3366: 3365: 3364: 3357: 3353: 3346: 3341: 3339: 3332: 3325: 3318: 3314: 3313: 3308: 3307: 3302: 3301: 3294: 3292: 3271: 3267: 3263: 3260: 3257: 3254: 3250: 3241: 3237: 3233: 3230: 3227: 3222: 3218: 3214: 3211: 3208: 3203: 3199: 3195: 3192: 3182: 3181: 3180: 3177: 3171: 3165: 3160: 3154: 3152: 3148: 3144: 3140: 3136: 3132: 3129: 3125: 3121: 3116: 3113: 3109: 3100: 3091: 3090:information. 3089: 3085: 3081: 3077: 3073: 3069: 3065: 3061: 3057: 3055: 3051: 3047: 3043: 3038: 3034: 3030: 3012: 3008: 3004: 2982: 2978: 2974: 2952: 2948: 2944: 2935: 2931: 2927: 2922: 2920: 2916: 2912: 2908: 2904: 2900: 2896: 2892: 2888: 2872: 2869: 2866: 2863: 2860: 2857: 2854: 2851: 2848: 2845: 2842: 2839: 2836: 2833: 2828: 2824: 2820: 2817: 2812: 2808: 2804: 2801: 2796: 2792: 2788: 2779: 2777: 2773: 2769: 2765: 2761: 2757: 2741: 2738: 2733: 2729: 2725: 2722: 2717: 2713: 2709: 2706: 2701: 2697: 2693: 2679: 2677: 2672: 2667: 2663: 2661: 2657: 2653: 2649: 2645: 2641: 2637: 2633: 2629: 2623: 2621: 2617: 2614: 2610: 2606: 2595: 2575: 2566: 2563: 2558: 2550: 2547: 2543: 2535: 2532: 2528: 2518: 2515: 2511: 2502: 2499: 2494: 2486: 2483: 2479: 2469: 2466: 2462: 2454: 2451: 2447: 2438: 2435: 2430: 2423: 2418: 2409: 2399: 2398: 2397: 2394: 2392: 2388: 2382: 2372: 2370: 2365: 2363: 2357: 2348: 2345: 2341: 2338: 2334: 2330: 2321: 2312: 2310: 2302: 2286: 2282: 2259: 2255: 2232: 2228: 2205: 2202: 2198: 2170: 2167: 2163: 2157: 2154: 2150: 2144: 2141: 2138: 2134: 2130: 2126: 2122: 2119: 2112: 2111: 2110: 2108: 2092: 2085: 2062: 2058: 2054: 2051: 2047: 2043: 2038: 2033: 2029: 2023: 2019: 2013: 2009: 2003: 2000: 1995: 1991: 1980: 1975: 1971: 1963: 1962: 1961: 1944: 1939: 1933: 1928: 1923: 1916: 1911: 1906: 1899: 1894: 1889: 1883: 1878: 1875: 1872: 1863: 1857: 1854: 1851: 1842: 1832: 1831: 1830: 1827: 1807: 1775: 1760: 1754: 1748: 1741: 1737: 1726: 1715: 1711: 1707: 1702: 1698: 1688: 1681: 1677: 1666: 1658: 1654: 1650: 1641: 1633: 1629: 1622: 1613: 1607: 1598: 1592: 1589: 1583: 1580: 1569: 1563: 1553: 1552: 1551: 1549: 1548: 1531: 1522: 1518: 1513: 1492: 1488: 1477: 1466: 1462: 1458: 1453: 1449: 1439: 1432: 1428: 1417: 1409: 1405: 1401: 1392: 1384: 1380: 1373: 1364: 1358: 1349: 1343: 1340: 1334: 1331: 1320: 1314: 1304: 1303: 1302: 1301: 1297: 1296:magnetization 1273: 1267: 1264: 1261: 1255: 1250: 1242: 1239: 1233: 1222: 1219: 1216: 1210: 1197: 1196: 1195: 1193: 1171: 1168: 1165: 1159: 1156: 1150: 1147: 1141: 1130: 1127: 1124: 1118: 1105: 1104: 1103: 1102:of the flux: 1101: 1097: 1093: 1071: 1068: 1065: 1059: 1053: 1050: 1047: 1041: 1038: 1035: 1029: 1022: 1021: 1020: 1018: 1014: 998: 978: 964: 941: 937: 933: 928: 924: 916: 906: 903: 900: 897: 894: 886: 882: 877: 870: 867: 864: 861: 858: 850: 846: 839: 836: 833: 827: 824: 821: 818: 815: 794: 793: 792: 776: 772: 749: 745: 724: 721: 718: 698: 672: 669: 666: 663: 660: 657: 651: 648: 645: 638: 634: 626: 623: 617: 607: 606: 605: 601: 587: 547: 527: 519: 503: 483: 461: 457: 432: 428: 424: 418: 415: 410: 403: 397: 393: 387: 383: 377: 373: 369: 365: 361: 358: 355: 348: 344: 336: 333: 327: 317: 316: 315: 311: 295: 291: 268: 264: 254: 250: 240: 236: 234: 230: 226: 220: 218: 214: 209: 207: 203: 199: 195: 192: 188: 184: 180: 176: 173: 169: 165: 161: 157: 152: 150: 146: 142: 141:T2 relaxation 138: 134: 130: 120: 118: 115: 111: 107: 103: 99: 95: 91: 87: 83: 79: 78:MRI sequences 75: 71: 67: 58: 54: 52: 48: 44:DTI Color Map 41: 36: 33:Diffusion MRI 31: 19: 9110:Neuroimaging 9056:Acute stroke 9022:Thermography 8777:scintigraphy 8767:Radionuclide 8755:pre-hospital 8601:Tractography 8590: 8520:Radiodensity 8422:calcium scan 8383:Quantitative 8093: 8089: 8079: 8054: 8050: 8040: 7997: 7993: 7987: 7970: 7966: 7960: 7925: 7921: 7911: 7890: 7883: 7848: 7844: 7783:(1): 20935. 7780: 7776: 7766: 7726:(1): 14982. 7723: 7719: 7709: 7674: 7670: 7660: 7645: 7612: 7608: 7601: 7564: 7560: 7507:(1): 10742. 7504: 7500: 7490: 7463: 7457: 7432: 7428: 7422: 7388:(3): 63–74. 7385: 7381: 7371: 7360:. Retrieved 7354: 7344: 7317: 7313: 7303: 7268: 7264: 7254: 7229: 7225: 7219: 7210: 7204: 7169: 7165: 7155: 7142: 7135: 7102: 7098: 7092: 7083: 7079: 7073: 7056: 7050: 7023: 7019: 7009: 6966: 6962: 6956: 6945:. Retrieved 6939: 6929: 6894: 6890: 6880: 6855: 6851: 6845: 6834:. Retrieved 6830: 6806:. Retrieved 6802: 6764: 6760: 6754: 6719: 6715: 6705: 6688: 6682: 6665: 6661: 6655: 6628: 6622: 6589: 6585: 6578: 6553: 6549: 6543: 6518: 6514: 6508: 6475: 6471: 6465: 6448: 6444: 6400: 6396: 6386: 6343: 6339: 6329: 6294: 6290: 6279: 6244: 6240: 6230: 6195: 6191: 6180: 6145: 6141: 6131: 6106: 6102: 6096: 6063: 6059: 6053: 6018: 6014: 6004: 5963: 5959: 5953: 5928: 5924: 5918: 5899: 5895: 5859: 5845:Tractography 5835:Connectogram 5822:tractography 5819: 5812: 5803: 5791: 5781: 5774: 5770: 5731: 5726:connectomics 5695:motor cortex 5687:tractography 5682:and a tumor. 5676:brain tumors 5657: 5633: 5612: 5593:white matter 5590: 5578: 5516: 5501: 5492: 5481:Please help 5476:verification 5473: 5455:Applications 5358:volume ratio 5357: 5355: 5160: 5158: 4992: 4990: 4842: 4840: 4673: 4671: 4513: 4511: 4444: 4353: 4111: 4074: 4068: 4061: 4054: 4047: 4040: 4033: 4026: 4019: 4012: 3965: 3744: 3742: 3656: 3654: 3550: 3469: 3467: 3436: 3362: 3355: 3351: 3344: 3342: 3337: 3330: 3323: 3316: 3310: 3304: 3300:eigenvectors 3298: 3295: 3290: 3288: 3175: 3169: 3163: 3155: 3142: 3139:microtubules 3130: 3117: 3105: 3083: 3079: 3075: 3071: 3067: 3063: 3058: 3054:eigenvectors 3049: 3045: 3041: 3036: 3032: 3028: 2923: 2918: 2914: 2910: 2906: 2902: 2898: 2894: 2890: 2886: 2780: 2767: 2763: 2759: 2685: 2668: 2664: 2659: 2655: 2651: 2647: 2643: 2639: 2635: 2631: 2627: 2624: 2619: 2615: 2612: 2601: 2592: 2395: 2384: 2368: 2366: 2362:tractography 2358: 2354: 2342: 2337:T2 weighting 2332: 2328: 2326: 2311: 2308: 2189: 2106: 2083: 2081: 1959: 1828: 1796: 1545: 1514: 1511: 1293: 1189: 1089: 970: 961: 690: 602: 448: 312: 246: 237: 233:tractography 221: 210: 202:brain tumors 197: 196: 187:white matter 178: 177: 164:white matter 153: 144: 128: 126: 123:Introduction 117:tractography 114:white matter 109: 105: 73: 69: 65: 64: 8945:Cardiac PET 8718:renal tract 8693:Gynecologic 8625:Techniques 8596:restriction 8571:Angiography 8554:Neurography 8500:Fluoroscopy 8446:Angiography 8427:angiography 8371:Techniques: 8332:Aortography 8322:Angiography 8302:Cystography 8292:Mammography 8234:Myelography 8229:Sialography 8198:radiography 8057:: 129–135. 7903:10027851300 7356:Radiopaedia 6941:Radiopaedia 6831:XRayPhysics 6697:10018514722 6346:(1): 4749. 5777:icosahedron 5699:spinal cord 5653:eigenvector 4674:planar case 4514:linear case 3306:eigenvalues 3289:We use the 3124:attenuation 3088:eigenvector 2930:diagonalize 2776:hyperboloid 2084:attenuation 1517:H.C. Torrey 168:grey matter 9094:Categories 8858:Full body: 8644:endoscopic 8618:Ultrasound 8547:functional 8344:Lymphogram 8339:Venography 8307:Arthrogram 7967:Biometrika 7362:2017-10-15 7086:: 459–461. 6984:2108/34611 6947:2017-10-15 6836:2017-10-15 6825:Hammer M. 6808:2018-03-15 6060:NeuroImage 5879:References 5840:Connectome 5795:tomography 5597:anisotropy 2676:Adolf Fick 2379:See also: 2190:where the 1100:divergence 191:anisotropy 9061:Pregnancy 8940:Brain PET 8908:gamma ray 8844:DMSA scan 8698:Obstetric 8591:diffusion 8586:Sequences 8564:perfusion 8456:Pulmonary 8403:Cone beam 8297:Pyelogram 8128:264099038 8112:0740-3194 8071:121103537 8051:Math. Ann 8010:CiteSeerX 7805:2045-2322 7740:2045-2322 7166:Neurology 7065:576214706 6934:Bhuta S. 6852:Radiology 6515:Radiology 6103:Radiology 5996:250787827 5865:classical 5609:diffusion 5426:λ 5420:⁡ 5406:λ 5396:λ 5386:λ 5335:λ 5329:⁡ 5301:λ 5295:⁡ 5289:− 5280:λ 5257:λ 5251:⁡ 5245:− 5236:λ 5213:λ 5207:⁡ 5201:− 5192:λ 5135:λ 5122:λ 5109:λ 5097:λ 5090:− 5081:λ 5068:λ 5048:− 4967:λ 4954:λ 4941:λ 4929:λ 4880:λ 4876:≃ 4867:λ 4863:≃ 4854:λ 4817:λ 4804:λ 4791:λ 4776:λ 4772:− 4763:λ 4711:λ 4707:≫ 4698:λ 4694:≃ 4685:λ 4648:λ 4635:λ 4622:λ 4610:λ 4606:− 4597:λ 4551:λ 4547:≃ 4538:λ 4534:≫ 4525:λ 4494:≥ 4485:λ 4481:≥ 4472:λ 4468:≥ 4459:λ 4410:λ 4397:λ 4384:λ 4371:λ 4365:⁡ 4322:λ 4304:λ 4286:λ 4258:λ 4252:⁡ 4246:− 4237:λ 4214:λ 4208:⁡ 4202:− 4193:λ 4170:λ 4164:⁡ 4158:− 4149:λ 3870:− 3862:Λ 3824:Λ 3813:− 3776:Λ 3711:λ 3698:λ 3685:λ 3634:λ 3607:λ 3580:λ 3559:Λ 3530:λ 3517:λ 3504:λ 3494:Λ 3451:⊥ 3447:λ 3405:λ 3392:λ 3380:⊥ 3376:λ 3159:Cartesian 3112:ellipsoid 3108:diffusion 2934:Cartesian 2772:ellipsoid 2669:In 1848, 2413:¯ 2315:ADC image 2305:Grayscale 2135:∑ 2131:− 2052:− 2044:∼ 2010:γ 1996:− 1879:⋅ 1867:→ 1858:⋅ 1846:→ 1811:→ 1779:→ 1770:∇ 1764:→ 1755:⋅ 1752:∇ 1730:→ 1708:− 1689:− 1670:→ 1645:→ 1623:− 1617:→ 1608:× 1602:→ 1593:γ 1573:→ 1515:In 1956, 1481:→ 1459:− 1440:− 1421:→ 1396:→ 1374:− 1368:→ 1359:× 1353:→ 1344:γ 1324:→ 1256:ρ 1247:∇ 1231:∂ 1211:ρ 1208:∂ 1157:⋅ 1154:∇ 1151:− 1139:∂ 1119:ρ 1116:∂ 1060:ρ 1057:∇ 1051:− 991:and flux 979:ρ 934:− 840:⁡ 664:⋅ 658:− 652:⁡ 568:Δ 548:δ 504:γ 416:δ 411:− 408:Δ 394:δ 374:γ 370:− 362:⁡ 243:Mechanism 102:membranes 86:diffusion 9079:Category 8931:positron 8451:Coronary 8120:37831659 7944:12353272 7867:15562495 7823:34686721 7758:34294771 7701:33282795 7637:18718789 7593:32373625 7539:31341212 7449:17515386 7414:22468186 7336:23876408 7295:17599699 7246:12044998 7196:19129507 7119:11276097 7042:11025519 7001:14173858 6993:17507813 6921:21454821 6872:23882093 6746:11865594 6738:15906300 6614:25910939 6500:19766099 6427:34227242 6378:33637807 6321:32694155 6271:32304291 6222:34132126 6172:22171354 6080:18495497 6037:16247738 5829:See also 5784:-tuple" 5767:Research 5715:dementia 5581:oncology 5527:penumbra 5356:and the 4845:, where 4841:For the 4676:, where 4672:For the 4516:, where 4512:For the 1017:gradient 253:moieties 82:contrast 9105:Tensors 9100:Imaging 8978:Optical 8960:PET-MRI 8740:Carotid 8735:Scrotal 8629:doppler 8559:Cardiac 8468:Thyroid 8412:Targets 8363:CT scan 8032:6080176 8002:Bibcode 7952:2048187 7875:1368461 7814:8536657 7785:Bibcode 7749:8298404 7692:7708343 7629:9403488 7584:7177010 7530:6656714 7509:Bibcode 7405:3314930 7286:2041910 7187:2677508 7127:7269302 6912:3384724 6769:Bibcode 6606:8946350 6558:Bibcode 6535:8351339 6492:7869892 6418:8928440 6397:Obesity 6369:7910493 6348:Bibcode 6312:7572819 6262:7261762 6213:9665421 6163:3235568 6123:3763909 6088:2660208 6045:8586494 5988:4001161 5968:Bibcode 5933:Bibcode 5910:8814916 5809:Summary 5722:in vivo 5697:to the 5664:lesions 2905:, and 2756:quadric 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Index

Diffusion imaging

MeSH
D038524
MRI sequences
contrast
diffusion
biological tissues
in vivo
macromolecules
membranes
white matter
tractography
voxel
T1
T2 relaxation
axonal
non-small-cell lung cancer
positron emission tomography
white matter
grey matter
cerebral cortex
axons
white matter
anisotropy
brain tumors
multiple sclerosis
edema
strokes
tensor

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