dMRI-Lab 1.0
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Functions | |
function | atti2apa (in dwifile, in gifile, in bifile, in pafile, in varargin) |
function atti2apa | ( | in | dwifile, |
in | gifile, | ||
in | bifile, | ||
in | pafile, | ||
in | varargin ) |
Computes the (apparent) Propagator Anisotropy (PA) according to a mono-exponential model for single-shell acquisitions as described in AMURA:
atti(u,b) = exp(-b*D_0(u)),
where D_0(u) is the Apparent Diffusion Coefficient measured at b=b0 for each direction 'u' within the unit sphere. The PA is defined in terms of the 'angle' between the true attenuation signal and its isotropic counterpart, which in AMURA is modeled as that with a homogeneous Diffusion Coefficente: D_iso = mean{D_0(u)}.
dwifile | A string specifying the file containing the diffusion-weighted images. |
gifile | A string specifying the file containing the gradient directions. |
bifile | A string specifying the the corresponding b-values of each entry in gi. |
pafile | A string specifying the file to save the computed PA. |
varargin | Optional arguments passed as -name value pairs. |
Mandatory Inputs:
Optional Arguments - General parameters:
pa = pa0^(3*epsilon)/(1-3*pa0^epsilon+3*pa0^(2*epsilon));
Use empty brackets, [], to avoid this correction and work with the raw PA (default: 0.4).
Parameters related to SH computations:
Example: