Docstrings · CLEARSWI.jl

CLEARSWI.Data — Type

Data(mag, phase, header, TEs)

Defines a struct as input for clearSWI

CLEARSWI.Options — Type

Options(;   mag_combine=:SNR,
            mag_sens=nothing,
            mag_softplus=true,
            phase_unwrap=:laplacian,
            phase_hp_sigma=[4,4,0],
            phase_scaling_type=:tanh,
            phase_scaling_strength=4,
            writesteps=nothing)

mag_combine selects the echo combination for the magnitude. Options are
- :SNR
- :average
- :last to select the last echo
- (:CNR => (:gm, :wm)) to optimize the contrast between two selected tissues with the possible tissues classes to select in src/tissue.jl, currently only working for 7T
- (:echo => 3) to select the 3rd echo
- (:closest => 15.3) to select the echo that is closest to 15.3 ms
- (:SE => 15.3) to simulate the contrast that would be achieved using a corresponding single-echo scan with 15.3 ms echo time.
If mag_sens is set to an array, it is used instead of CLEAR-SWI sensitivity estimation. This can also be set to mag_sens=[1] to use the constant sensitivity of 1 and effectively avoid sensitivity correction. To change the sigmamm value of the expected bias field size, set it to i.e. `magsens=(:sigma_mm => 7)`. The default is 7mm.
To deactivate scaling of the combined magnitude with the softplus function, use mag_softplus=false.
phase_unwrap is either :laplacian, :romeo, or :laplacianslice (slicewise laplacian unwrapping)
The phase_hp_sigma is used for high-pass filtering and is given in voxel for the [x,y,z]-dimension.
phase_scaling_type is the scaling function to create the phase mask and can be :tanh or :negativetanh for sigmoidal filtering, or :positive, :negative, and :triangular for traditional SWI application.
phase_scaling_strength adjusts the strength of the created phase mask. A higher phase_scaling_strength is a stronger phase appearance. With a traditional SWI phase_scaling_type it corresponds to the power or number of phase mask multiplications.
Set writesteps to the path, where intermediate steps should be saved, e.g. writesteps="/tmp/clearswi_steps". If set to nothing, intermediate steps won't be saved.
Set qsm to true

CLEARSWI.calculateSWI — Function

calculateSWI(data::Data, options::Options=Options())

Returns the calculated SWI using 'data' and 'options'.

Examples

julia> TEs = [4,8,12]
julia> data = Data(mag, phase, header(mag), TEs);
julia> swi = calculateSWI(data);

With Options

Options(;   mag_combine=:SNR,
            mag_sens=nothing,
            mag_softplus=true,
            phase_unwrap=:laplacian,
            phase_hp_sigma=[4,4,0],
            phase_scaling_type=:tanh,
            phase_scaling_strength=4,
            writesteps=nothing)

mag_combine selects the echo combination for the magnitude. Options are
- :SNR
- :average
- :last to select the last echo
- (:CNR => (:gm, :wm)) to optimize the contrast between two selected tissues with the possible tissues classes to select in src/tissue.jl, currently only working for 7T
- (:echo => 3) to select the 3rd echo
- (:closest => 15.3) to select the echo that is closest to 15.3 ms
- (:SE => 15.3) to simulate the contrast that would be achieved using a corresponding single-echo scan with 15.3 ms echo time.
If mag_sens is set to an array, it is used instead of CLEAR-SWI sensitivity estimation. This can also be set to mag_sens=[1] to use the constant sensitivity of 1 and effectively avoid sensitivity correction. To change the sigmamm value of the expected bias field size, set it to i.e. `magsens=(:sigma_mm => 7)`. The default is 7mm.
To deactivate scaling of the combined magnitude with the softplus function, use mag_softplus=false.
phase_unwrap is either :laplacian, :romeo, or :laplacianslice (slicewise laplacian unwrapping)
The phase_hp_sigma is used for high-pass filtering and is given in voxel for the [x,y,z]-dimension.
phase_scaling_type is the scaling function to create the phase mask and can be :tanh or :negativetanh for sigmoidal filtering, or :positive, :negative, and :triangular for traditional SWI application.
phase_scaling_strength adjusts the strength of the created phase mask. A higher phase_scaling_strength is a stronger phase appearance. With a traditional SWI phase_scaling_type it corresponds to the power or number of phase mask multiplications.
Set writesteps to the path, where intermediate steps should be saved, e.g. writesteps="/tmp/clearswi_steps". If set to nothing, intermediate steps won't be saved.
Set qsm to true

Examples

julia> TEs = [4,8,12]
julia> data = Data(mag, phase, header(mag), TEs);
julia> options = Options(phase_hp_sigma=[10,10,5], mag_softplus=false)
julia> swi = calculateSWI(data, options);

CLEARSWI.createIntensityProjection — Method

createIntensityProjection(S::AbstractArray{T,3}, func, d=7) where T

Calculates an intensity projection over the 3rd dimension of S with the function func over d slices. Good function are minimum, maximum, mean, std, ...

Examples

julia> using Statistics
julia> a = rand(Float64, (64,64,20))
julia> createIntensityProjection(a, std)

CLEARSWI.createMIP — Function

createMIP(S::AbstractArray{<:Number,3}, d=7)

Creates minimum intensity projection of S over d slices.

Examples

julia> TEs = [4,8,12]
julia> data = Data(mag, phase, header(mag), TEs);
julia> swi = calculateSWI(data);
julia> mip = createMIP(swi);