def init_enhance_and_skullstrip_bold_wf(name='enhance_and_skullstrip_bold_wf',
omp_nthreads=1):
workflow = pe.Workflow(name=name)
inputnode = pe.Node(niu.IdentityInterface(fields=['in_file']),
name='inputnode')
outputnode = pe.Node(niu.IdentityInterface(fields=[
'mask_file', 'skull_stripped_file', 'bias_corrected_file', 'out_report'
]),
name='outputnode')
n4_correct = pe.Node(ants.N4BiasFieldCorrection(dimension=3,
copy_header=True,
num_threads=omp_nthreads),
name='n4_correct',
n_procs=omp_nthreads)
skullstrip_first_pass = pe.Node(fsl.BET(frac=0.2, mask=True),
name='skullstrip_first_pass')
unifize = pe.Node(afni.Unifize(t2=True,
outputtype='NIFTI_GZ',
args='-clfrac 0.4',
out_file="uni.nii.gz"),
name='unifize')
skullstrip_second_pass = pe.Node(afni.Automask(dilate=1,
outputtype='NIFTI_GZ'),
name='skullstrip_second_pass')
combine_masks = pe.Node(fsl.BinaryMaths(operation='mul'),
name='combine_masks')
apply_mask = pe.Node(fsl.ApplyMask(), name='apply_mask')
mask_reportlet = pe.Node(SimpleShowMaskRPT(), name='mask_reportlet')
workflow.connect([
(inputnode, n4_correct, [('in_file', 'input_image')]),
(n4_correct, skullstrip_first_pass, [('output_image', 'in_file')]),
(skullstrip_first_pass, unifize, [('out_file', 'in_file')]),
(unifize, skullstrip_second_pass, [('out_file', 'in_file')]),
(skullstrip_first_pass, combine_masks, [('mask_file', 'in_file')]),
(skullstrip_second_pass, combine_masks, [('out_file', 'operand_file')
]),
(unifize, apply_mask, [('out_file', 'in_file')]),
(combine_masks, apply_mask, [('out_file', 'mask_file')]),
(n4_correct, mask_reportlet, [('output_image', 'background_file')]),
(combine_masks, mask_reportlet, [('out_file', 'mask_file')]),
(combine_masks, outputnode, [('out_file', 'mask_file')]),
(mask_reportlet, outputnode, [('out_report', 'out_report')]),
(apply_mask, outputnode, [('out_file', 'skull_stripped_file')]),
(n4_correct, outputnode, [('output_image', 'bias_corrected_file')]),
])
return workflow
def init_skullstrip_epi_wf(name='skullstrip_epi_wf'):
workflow = pe.Workflow(name=name)
inputnode = pe.Node(niu.IdentityInterface(fields=['in_file']),
name='inputnode')
outputnode = pe.Node(niu.IdentityInterface(
fields=['mask_file', 'skull_stripped_file', 'out_report']),
name='outputnode')
skullstrip_first_pass = pe.Node(fsl.BET(frac=0.2, mask=True),
name='skullstrip_first_pass')
skullstrip_second_pass = pe.Node(afni.Automask(dilate=1,
outputtype='NIFTI_GZ'),
name='skullstrip_second_pass')
combine_masks = pe.Node(fsl.BinaryMaths(operation='mul'),
name='combine_masks')
apply_mask = pe.Node(fsl.ApplyMask(), name='apply_mask')
mask_reportlet = pe.Node(SimpleShowMaskRPT(), name='mask_reportlet')
workflow.connect([
(inputnode, skullstrip_first_pass, [('in_file', 'in_file')]),
(skullstrip_first_pass, skullstrip_second_pass, [('out_file',
'in_file')]),
(skullstrip_first_pass, combine_masks, [('mask_file', 'in_file')]),
(skullstrip_second_pass, combine_masks, [('out_file', 'operand_file')
]),
(combine_masks, outputnode, [('out_file', 'mask_file')]),
# Masked file
(inputnode, apply_mask, [('in_file', 'in_file')]),
(combine_masks, apply_mask, [('out_file', 'mask_file')]),
(apply_mask, outputnode, [('out_file', 'skull_stripped_file')]),
# Reportlet
(inputnode, mask_reportlet, [('in_file', 'background_file')]),
(combine_masks, mask_reportlet, [('out_file', 'mask_file')]),
(mask_reportlet, outputnode, [('out_report', 'out_report')]),
])
return workflow
def init_sdc_unwarp_wf(reportlets_dir,
omp_nthreads,
fmap_bspline,
fmap_demean,
debug,
name='sdc_unwarp_wf'):
"""
This workflow takes in a displacements fieldmap and calculates the corresponding
displacements field (in other words, an ANTs-compatible warp file).
It also calculates a new mask for the input dataset that takes into account the distortions.
The mask is restricted to the field of view of the fieldmap since outside of it corrections
could not be performed.
.. workflow ::
:graph2use: orig
:simple_form: yes
from fmriprep.workflows.fieldmap.unwarp import init_sdc_unwarp_wf
wf = init_sdc_unwarp_wf(reportlets_dir='.', omp_nthreads=8,
fmap_bspline=False, fmap_demean=True,
debug=False)
Inputs
in_reference
the reference image
in_mask
a brain mask corresponding to ``in_reference``
name_source
path to the original _bold file being unwarped
fmap
the fieldmap in Hz
fmap_ref
the reference (anatomical) image corresponding to ``fmap``
fmap_mask
a brain mask corresponding to ``fmap``
Outputs
out_reference
the ``in_reference`` after unwarping
out_reference_brain
the ``in_reference`` after unwarping and skullstripping
out_warp
the corresponding :abbr:`DFM (displacements field map)` compatible with
ANTs
out_jacobian
the jacobian of the field (for drop-out alleviation)
out_mask
mask of the unwarped input file
out_mask_report
reportled for the skullstripping
"""
workflow = pe.Workflow(name=name)
inputnode = pe.Node(niu.IdentityInterface(fields=[
'in_reference', 'in_reference_brain', 'in_mask', 'name_source',
'fmap_ref', 'fmap_mask', 'fmap'
]),
name='inputnode')
outputnode = pe.Node(niu.IdentityInterface(fields=[
'out_reference', 'out_reference_brain', 'out_warp', 'out_mask',
'out_jacobian', 'out_mask_report'
]),
name='outputnode')
meta = pe.Node(ReadSidecarJSON(), name='meta')
# Register the reference of the fieldmap to the reference
# of the target image (the one that shall be corrected)
ants_settings = pkgr.resource_filename('fmriprep',
'data/fmap-any_registration.json')
if debug:
ants_settings = pkgr.resource_filename(
'fmriprep', 'data/fmap-any_registration_testing.json')
fmap2ref_reg = pe.Node(ANTSRegistrationRPT(
generate_report=True,
from_file=ants_settings,
output_inverse_warped_image=True,
output_warped_image=True,
num_threads=omp_nthreads),
name='fmap2ref_reg')
fmap2ref_reg.interface.num_threads = omp_nthreads
ds_reg = pe.Node(DerivativesDataSink(base_directory=reportlets_dir,
suffix='fmap_reg'),
name='ds_reg')
# Map the VSM into the EPI space
fmap2ref_apply = pe.Node(ANTSApplyTransformsRPT(generate_report=True,
dimension=3,
interpolation='BSpline',
float=True),
name='fmap2ref_apply')
fmap_mask2ref_apply = pe.Node(ANTSApplyTransformsRPT(
generate_report=False,
dimension=3,
interpolation='NearestNeighbor',
float=True),
name='fmap_mask2ref_apply')
ds_reg_vsm = pe.Node(DerivativesDataSink(base_directory=reportlets_dir,
suffix='fmap_reg_vsm'),
name='ds_reg_vsm')
# Fieldmap to rads and then to voxels (VSM - voxel shift map)
torads = pe.Node(niu.Function(function=_hz2rads), name='torads')
gen_vsm = pe.Node(fsl.FUGUE(save_unmasked_shift=True), name='gen_vsm')
# Convert the VSM into a DFM (displacements field map)
# or: FUGUE shift to ANTS warping.
vsm2dfm = pe.Node(itk.FUGUEvsm2ANTSwarp(), name='vsm2dfm')
jac_dfm = pe.Node(ants.CreateJacobianDeterminantImage(
imageDimension=3, outputImage='jacobian.nii.gz'),
name='jac_dfm')
unwarp_reference = pe.Node(ANTSApplyTransformsRPT(
dimension=3,
generate_report=False,
float=True,
interpolation='LanczosWindowedSinc'),
name='unwarp_reference')
fieldmap_fov_mask = pe.Node(niu.Function(function=_fill_with_ones),
name='fieldmap_fov_mask')
fmap_fov2ref_apply = pe.Node(ANTSApplyTransformsRPT(
generate_report=False,
dimension=3,
interpolation='NearestNeighbor',
float=True),
name='fmap_fov2ref_apply')
apply_fov_mask = pe.Node(fsl.ApplyMask(), name="apply_fov_mask")
enhance_and_skullstrip_epi_wf = init_enhance_and_skullstrip_epi_wf()
workflow.connect([
(inputnode, meta, [('name_source', 'in_file')]),
(inputnode, fmap2ref_reg, [('fmap_ref', 'moving_image')]),
(inputnode, fmap2ref_apply, [('in_reference', 'reference_image')]),
(fmap2ref_reg, fmap2ref_apply, [('composite_transform', 'transforms')
]),
(inputnode, fmap_mask2ref_apply, [('in_reference', 'reference_image')
]),
(fmap2ref_reg, fmap_mask2ref_apply, [('composite_transform',
'transforms')]),
(inputnode, ds_reg_vsm, [('name_source', 'source_file')]),
(fmap2ref_apply, ds_reg_vsm, [('out_report', 'in_file')]),
(inputnode, fmap2ref_reg, [('in_reference_brain', 'fixed_image')]),
(inputnode, ds_reg, [('name_source', 'source_file')]),
(fmap2ref_reg, ds_reg, [('out_report', 'in_file')]),
(inputnode, fmap2ref_apply, [('fmap', 'input_image')]),
(inputnode, fmap_mask2ref_apply, [('fmap_mask', 'input_image')]),
(fmap2ref_apply, torads, [('output_image', 'in_file')]),
(meta, gen_vsm, [(('out_dict', _get_ec), 'dwell_time'),
(('out_dict', _get_pedir_fugue), 'unwarp_direction')
]),
(meta, vsm2dfm, [(('out_dict', _get_pedir_bids), 'pe_dir')]),
(torads, gen_vsm, [('out', 'fmap_in_file')]),
(vsm2dfm, unwarp_reference, [('out_file', 'transforms')]),
(inputnode, unwarp_reference, [('in_reference', 'reference_image')]),
(inputnode, unwarp_reference, [('in_reference', 'input_image')]),
(vsm2dfm, outputnode, [('out_file', 'out_warp')]),
(vsm2dfm, jac_dfm, [('out_file', 'deformationField')]),
(inputnode, fieldmap_fov_mask, [('fmap_ref', 'in_file')]),
(fieldmap_fov_mask, fmap_fov2ref_apply, [('out', 'input_image')]),
(inputnode, fmap_fov2ref_apply, [('in_reference', 'reference_image')]),
(fmap2ref_reg, fmap_fov2ref_apply, [('composite_transform',
'transforms')]),
(fmap_fov2ref_apply, apply_fov_mask, [('output_image', 'mask_file')]),
(unwarp_reference, apply_fov_mask, [('output_image', 'in_file')]),
(apply_fov_mask, enhance_and_skullstrip_epi_wf,
[('out_file', 'inputnode.in_file')]),
(apply_fov_mask, outputnode, [('out_file', 'out_reference')]),
(enhance_and_skullstrip_epi_wf, outputnode,
[('outputnode.mask_file', 'out_mask'),
('outputnode.out_report', 'out_mask_report'),
('outputnode.skull_stripped_file', 'out_reference_brain')]),
(jac_dfm, outputnode, [('jacobian_image', 'out_jacobian')]),
])
if not fmap_bspline:
workflow.connect([(fmap_mask2ref_apply, gen_vsm, [('output_image',
'mask_file')])])
if fmap_demean:
# Demean within mask
demean = pe.Node(niu.Function(function=_demean), name='demean')
workflow.connect([
(gen_vsm, demean, [('shift_out_file', 'in_file')]),
(fmap_mask2ref_apply, demean, [('output_image', 'in_mask')]),
(demean, vsm2dfm, [('out', 'in_file')]),
])
else:
workflow.connect([
(gen_vsm, vsm2dfm, [('shift_out_file', 'in_file')]),
])
return workflow
def init_skullstrip_bold_wf(name='skullstrip_bold_wf'):
"""
This workflow applies skull-stripping to a BOLD image.
It is intended to be used on an image that has previously been
bias-corrected with
:py:func:`~fmriprep.workflows.bold.util.init_enhance_and_skullstrip_bold_wf`
.. workflow ::
:graph2use: orig
:simple_form: yes
from fmriprep.workflows.bold.util import init_skullstrip_bold_wf
wf = init_skullstrip_bold_wf()
Inputs
in_file
BOLD image (single volume)
Outputs
skull_stripped_file
the ``in_file`` after skull-stripping
mask_file
mask of the skull-stripped input file
out_report
reportlet for the skull-stripping
"""
workflow = pe.Workflow(name=name)
inputnode = pe.Node(niu.IdentityInterface(fields=['in_file']),
name='inputnode')
outputnode = pe.Node(niu.IdentityInterface(
fields=['mask_file', 'skull_stripped_file', 'out_report']),
name='outputnode')
skullstrip_first_pass = pe.Node(fsl.BET(frac=0.2, mask=True),
name='skullstrip_first_pass')
skullstrip_second_pass = pe.Node(afni.Automask(dilate=1,
outputtype='NIFTI_GZ'),
name='skullstrip_second_pass')
combine_masks = pe.Node(fsl.BinaryMaths(operation='mul'),
name='combine_masks')
apply_mask = pe.Node(fsl.ApplyMask(), name='apply_mask')
mask_reportlet = pe.Node(SimpleShowMaskRPT(), name='mask_reportlet')
workflow.connect([
(inputnode, skullstrip_first_pass, [('in_file', 'in_file')]),
(skullstrip_first_pass, skullstrip_second_pass, [('out_file',
'in_file')]),
(skullstrip_first_pass, combine_masks, [('mask_file', 'in_file')]),
(skullstrip_second_pass, combine_masks, [('out_file', 'operand_file')
]),
(combine_masks, outputnode, [('out_file', 'mask_file')]),
# Masked file
(inputnode, apply_mask, [('in_file', 'in_file')]),
(combine_masks, apply_mask, [('out_file', 'mask_file')]),
(apply_mask, outputnode, [('out_file', 'skull_stripped_file')]),
# Reportlet
(inputnode, mask_reportlet, [('in_file', 'background_file')]),
(combine_masks, mask_reportlet, [('out_file', 'mask_file')]),
(mask_reportlet, outputnode, [('out_report', 'out_report')]),
])
return workflow
def init_enhance_and_skullstrip_bold_wf(name='enhance_and_skullstrip_bold_wf',
omp_nthreads=1):
"""
This workflow takes in a BOLD volume, and attempts to enhance the contrast
between gray and white matter, and skull-stripping the result.
.. workflow ::
:graph2use: orig
:simple_form: yes
from fmriprep.workflows.bold.util import init_enhance_and_skullstrip_bold_wf
wf = init_enhance_and_skullstrip_bold_wf(omp_nthreads=1)
Inputs
in_file
BOLD image (single volume)
Outputs
bias_corrected_file
the ``in_file`` after `N4BiasFieldCorrection`_
skull_stripped_file
the ``bias_corrected_file`` after skull-stripping
mask_file
mask of the skull-stripped input file
out_report
reportlet for the skull-stripping
.. _N4BiasFieldCorrection: https://hdl.handle.net/10380/3053
"""
workflow = pe.Workflow(name=name)
inputnode = pe.Node(niu.IdentityInterface(fields=['in_file']),
name='inputnode')
outputnode = pe.Node(niu.IdentityInterface(fields=[
'mask_file', 'skull_stripped_file', 'bias_corrected_file', 'out_report'
]),
name='outputnode')
n4_correct = pe.Node(ants.N4BiasFieldCorrection(dimension=3,
copy_header=True),
name='n4_correct',
n_procs=omp_nthreads)
skullstrip_first_pass = pe.Node(fsl.BET(frac=0.2, mask=True),
name='skullstrip_first_pass')
unifize = pe.Node(afni.Unifize(t2=True,
outputtype='NIFTI_GZ',
args='-clfrac 0.4',
out_file="uni.nii.gz"),
name='unifize')
skullstrip_second_pass = pe.Node(afni.Automask(dilate=1,
outputtype='NIFTI_GZ'),
name='skullstrip_second_pass')
combine_masks = pe.Node(fsl.BinaryMaths(operation='mul'),
name='combine_masks')
apply_mask = pe.Node(fsl.ApplyMask(), name='apply_mask')
copy_xform = pe.Node(CopyXForm(),
name='copy_xform',
mem_gb=0.1,
run_without_submitting=True)
mask_reportlet = pe.Node(SimpleShowMaskRPT(), name='mask_reportlet')
workflow.connect([
(inputnode, n4_correct, [('in_file', 'input_image')]),
(inputnode, copy_xform, [('in_file', 'hdr_file')]),
(n4_correct, skullstrip_first_pass, [('output_image', 'in_file')]),
(skullstrip_first_pass, unifize, [('out_file', 'in_file')]),
(unifize, skullstrip_second_pass, [('out_file', 'in_file')]),
(skullstrip_first_pass, combine_masks, [('mask_file', 'in_file')]),
(skullstrip_second_pass, combine_masks, [('out_file', 'operand_file')
]),
(unifize, apply_mask, [('out_file', 'in_file')]),
(combine_masks, apply_mask, [('out_file', 'mask_file')]),
(n4_correct, mask_reportlet, [('output_image', 'background_file')]),
(combine_masks, mask_reportlet, [('out_file', 'mask_file')]),
(combine_masks, outputnode, [('out_file', 'mask_file')]),
(mask_reportlet, outputnode, [('out_report', 'out_report')]),
(apply_mask, copy_xform, [('out_file', 'in_file')]),
(copy_xform, outputnode, [('out_file', 'skull_stripped_file')]),
(n4_correct, outputnode, [('output_image', 'bias_corrected_file')]),
])
return workflow
def epi_mni_align(settings, name='SpatialNormalization'):
"""
Uses FSL FLIRT with the BBR cost function to find the transform that
maps the EPI space into the MNI152-nonlinear-symmetric atlas.
The input epi_mean is the averaged and brain-masked EPI timeseries
Returns the EPI mean resampled in MNI space (for checking out registration) and
the associated "lobe" parcellation in EPI space.
.. workflow::
from mriqc.workflows.functional import epi_mni_align
wf = epi_mni_align({})
"""
from niworkflows.data import get_mni_icbm152_nlin_asym_09c as get_template
from niworkflows.interfaces.registration import (RobustMNINormalizationRPT
as RobustMNINormalization)
from pkg_resources import resource_filename as pkgrf
# Get settings
testing = settings.get('testing', False)
n_procs = settings.get('n_procs', 1)
ants_nthreads = settings.get('ants_nthreads', DEFAULTS['ants_nthreads'])
# Init template
mni_template = get_template()
workflow = pe.Workflow(name=name)
inputnode = pe.Node(niu.IdentityInterface(fields=['epi_mean', 'epi_mask']),
name='inputnode')
outputnode = pe.Node(
niu.IdentityInterface(fields=['epi_mni', 'epi_parc', 'report']),
name='outputnode')
epimask = pe.Node(fsl.ApplyMask(), name='EPIApplyMask')
n4itk = pe.Node(ants.N4BiasFieldCorrection(dimension=3), name='SharpenEPI')
norm = pe.Node(RobustMNINormalization(
num_threads=ants_nthreads,
float=settings.get('ants_float', False),
template='mni_icbm152_nlin_asym_09c',
reference_image=pkgrf('mriqc', 'data/mni/2mm_T2_brain.nii.gz'),
flavor='testing' if testing else 'precise',
moving='EPI',
generate_report=True,
),
name='EPI2MNI',
num_threads=n_procs,
mem_gb=3)
# Warp segmentation into EPI space
invt = pe.Node(ants.ApplyTransforms(float=True,
input_image=op.join(
mni_template, '1mm_parc.nii.gz'),
dimension=3,
default_value=0,
interpolation='NearestNeighbor'),
name='ResampleSegmentation')
workflow.connect([
(inputnode, invt, [('epi_mean', 'reference_image')]),
(inputnode, n4itk, [('epi_mean', 'input_image')]),
(inputnode, epimask, [('epi_mask', 'mask_file')]),
(n4itk, epimask, [('output_image', 'in_file')]),
(epimask, norm, [('out_file', 'moving_image')]),
(norm, invt, [('inverse_composite_transform', 'transforms')]),
(invt, outputnode, [('output_image', 'epi_parc')]),
(norm, outputnode, [('warped_image', 'epi_mni'),
('out_report', 'report')]),
])
return workflow
def init_enhance_and_skullstrip_bold_wf(name='enhance_and_skullstrip_bold_wf',
omp_nthreads=1,
enhance_t2=False):
"""
This workflow takes in a :abbr:`BOLD (blood-oxygen level-dependant)`
:abbr:`fMRI (functional MRI)` average/summary (e.g. a reference image
averaging non-steady-state timepoints), and sharpens the histogram
with the application of the N4 algorithm for removing the
:abbr:`INU (intensity non-uniformity)` bias field and calculates a signal
mask.
Steps of this workflow are:
1. Calculate a conservative mask using Nilearn's ``create_epi_mask``.
2. Run ANTs' ``N4BiasFieldCorrection`` on the input
:abbr:`BOLD (blood-oxygen level-dependant)` average, using the
mask generated in 1) instead of the internal Otsu thresholding.
3. Calculate a loose mask using FSL's ``bet``, with one mathematical morphology
dilation of one iteration and a sphere of 6mm as structuring element.
4. Mask the :abbr:`INU (intensity non-uniformity)`-corrected image
with the latest mask calculated in 3), then use AFNI's ``3dUnifize``
to *standardize* the T2* contrast distribution.
5. Calculate a mask using AFNI's ``3dAutomask`` after the contrast
enhancement of 4).
6. Calculate a final mask as the intersection of 3) and 5).
7. Apply final mask on the enhanced reference.
.. workflow ::
:graph2use: orig
:simple_form: yes
from fmriprep.workflows.bold.util import init_enhance_and_skullstrip_bold_wf
wf = init_enhance_and_skullstrip_bold_wf(omp_nthreads=1)
**Parameters**
name : str
Name of workflow (default: ``enhance_and_skullstrip_bold_wf``)
omp_nthreads : int
number of threads available to parallel nodes
enhance_t2 : bool
perform logarithmic transform of input BOLD image to improve contrast
before calculating the preliminary mask
**Inputs**
in_file
BOLD image (single volume)
**Outputs**
bias_corrected_file
the ``in_file`` after `N4BiasFieldCorrection`_
skull_stripped_file
the ``bias_corrected_file`` after skull-stripping
mask_file
mask of the skull-stripped input file
out_report
reportlet for the skull-stripping
.. _N4BiasFieldCorrection: https://hdl.handle.net/10380/3053
"""
workflow = pe.Workflow(name=name)
inputnode = pe.Node(niu.IdentityInterface(fields=['in_file']),
name='inputnode')
outputnode = pe.Node(niu.IdentityInterface(
fields=['mask_file', 'skull_stripped_file', 'bias_corrected_file']),
name='outputnode')
# Create a loose mask to avoid N4 internal's Otsu mask
n4_mask = pe.Node(MaskEPI(upper_cutoff=0.75,
enhance_t2=enhance_t2,
opening=1,
no_sanitize=True),
name='n4_mask')
# Run N4 normally, force num_threads=1 for stability (images are small, no need for >1)
n4_correct = pe.Node(ants.N4BiasFieldCorrection(dimension=3,
copy_header=True),
name='n4_correct',
n_procs=1)
# Create a generous BET mask out of the bias-corrected EPI
skullstrip_first_pass = pe.Node(fsl.BET(frac=0.2, mask=True),
name='skullstrip_first_pass')
bet_dilate = pe.Node(fsl.DilateImage(operation='max',
kernel_shape='sphere',
kernel_size=6.0,
internal_datatype='char'),
name='skullstrip_first_dilate')
bet_mask = pe.Node(fsl.ApplyMask(), name='skullstrip_first_mask')
# Use AFNI's unifize for T2 constrast & fix header
unifize = pe.Node(
afni.Unifize(
t2=True,
outputtype='NIFTI_GZ',
# Default -clfrac is 0.1, 0.4 was too conservative
# -rbt because I'm a Jedi AFNI Master (see 3dUnifize's documentation)
args='-clfrac 0.2 -rbt 18.3 65.0 90.0',
out_file="uni.nii.gz"),
name='unifize')
fixhdr_unifize = pe.Node(CopyXForm(), name='fixhdr_unifize', mem_gb=0.1)
# Run ANFI's 3dAutomask to extract a refined brain mask
skullstrip_second_pass = pe.Node(afni.Automask(dilate=1,
outputtype='NIFTI_GZ'),
name='skullstrip_second_pass')
fixhdr_skullstrip2 = pe.Node(CopyXForm(),
name='fixhdr_skullstrip2',
mem_gb=0.1)
# Take intersection of both masks
combine_masks = pe.Node(fsl.BinaryMaths(operation='mul'),
name='combine_masks')
# Compute masked brain
apply_mask = pe.Node(fsl.ApplyMask(), name='apply_mask')
workflow.connect([
(inputnode, n4_mask, [('in_file', 'in_files')]),
(inputnode, n4_correct, [('in_file', 'input_image')]),
(inputnode, fixhdr_unifize, [('in_file', 'hdr_file')]),
(inputnode, fixhdr_skullstrip2, [('in_file', 'hdr_file')]),
(n4_mask, n4_correct, [('out_mask', 'mask_image')]),
(n4_correct, skullstrip_first_pass, [('output_image', 'in_file')]),
(skullstrip_first_pass, bet_dilate, [('mask_file', 'in_file')]),
(bet_dilate, bet_mask, [('out_file', 'mask_file')]),
(skullstrip_first_pass, bet_mask, [('out_file', 'in_file')]),
(bet_mask, unifize, [('out_file', 'in_file')]),
(unifize, fixhdr_unifize, [('out_file', 'in_file')]),
(fixhdr_unifize, skullstrip_second_pass, [('out_file', 'in_file')]),
(skullstrip_first_pass, combine_masks, [('mask_file', 'in_file')]),
(skullstrip_second_pass, fixhdr_skullstrip2, [('out_file', 'in_file')
]),
(fixhdr_skullstrip2, combine_masks, [('out_file', 'operand_file')]),
(fixhdr_unifize, apply_mask, [('out_file', 'in_file')]),
(combine_masks, apply_mask, [('out_file', 'mask_file')]),
(combine_masks, outputnode, [('out_file', 'mask_file')]),
(apply_mask, outputnode, [('out_file', 'skull_stripped_file')]),
(n4_correct, outputnode, [('output_image', 'bias_corrected_file')]),
])
return workflow
def init_fmap_wf(reportlets_dir, omp_nthreads, fmap_bspline, name='fmap_wf'):
"""
Fieldmap workflow - when we have a sequence that directly measures the fieldmap
we just need to mask it (using the corresponding magnitude image) to remove the
noise in the surrounding air region, and ensure that units are Hz.
.. workflow ::
:graph2use: orig
:simple_form: yes
from fmriprep.workflows.fieldmap.fmap import init_fmap_wf
wf = init_fmap_wf(reportlets_dir='.', omp_nthreads=6,
fmap_bspline=False)
"""
workflow = pe.Workflow(name=name)
inputnode = pe.Node(niu.IdentityInterface(
fields=['magnitude', 'fieldmap']), name='inputnode')
outputnode = pe.Node(niu.IdentityInterface(fields=['fmap', 'fmap_ref', 'fmap_mask']),
name='outputnode')
# Merge input magnitude images
magmrg = pe.Node(IntraModalMerge(), name='magmrg')
# Merge input fieldmap images
fmapmrg = pe.Node(IntraModalMerge(zero_based_avg=False, hmc=False),
name='fmapmrg')
# de-gradient the fields ("bias/illumination artifact")
n4_correct = pe.Node(ants.N4BiasFieldCorrection(dimension=3, copy_header=True),
name='n4_correct', n_procs=omp_nthreads)
bet = pe.Node(BETRPT(generate_report=True, frac=0.6, mask=True),
name='bet')
ds_fmap_mask = pe.Node(DerivativesDataSink(
base_directory=reportlets_dir, suffix='fmap_mask'),
name='ds_fmap_mask', run_without_submitting=True)
workflow.connect([
(inputnode, magmrg, [('magnitude', 'in_files')]),
(inputnode, fmapmrg, [('fieldmap', 'in_files')]),
(magmrg, n4_correct, [('out_file', 'input_image')]),
(n4_correct, bet, [('output_image', 'in_file')]),
(bet, outputnode, [('mask_file', 'fmap_mask'),
('out_file', 'fmap_ref')]),
(inputnode, ds_fmap_mask, [('fieldmap', 'source_file')]),
(bet, ds_fmap_mask, [('out_report', 'in_file')]),
])
if fmap_bspline:
# despike_threshold=1.0, mask_erode=1),
fmapenh = pe.Node(FieldEnhance(unwrap=False, despike=False),
name='fmapenh', mem_gb=4, n_procs=omp_nthreads)
workflow.connect([
(bet, fmapenh, [('mask_file', 'in_mask'),
('out_file', 'in_magnitude')]),
(fmapmrg, fmapenh, [('out_file', 'in_file')]),
(fmapenh, outputnode, [('out_file', 'fmap')]),
])
else:
torads = pe.Node(niu.Function(output_names=['out_file', 'cutoff_hz'],
function=_torads), name='torads')
prelude = pe.Node(fsl.PRELUDE(), name='prelude')
tohz = pe.Node(niu.Function(function=_tohz), name='tohz')
denoise = pe.Node(fsl.SpatialFilter(operation='median', kernel_shape='sphere',
kernel_size=3), name='denoise')
demean = pe.Node(niu.Function(function=demean_image), name='demean')
cleanup_wf = cleanup_edge_pipeline(name='cleanup_wf')
applymsk = pe.Node(fsl.ApplyMask(), name='applymsk')
workflow.connect([
(bet, prelude, [('mask_file', 'mask_file'),
('out_file', 'magnitude_file')]),
(fmapmrg, torads, [('out_file', 'in_file')]),
(torads, tohz, [('cutoff_hz', 'cutoff_hz')]),
(torads, prelude, [('out_file', 'phase_file')]),
(prelude, tohz, [('unwrapped_phase_file', 'in_file')]),
(tohz, denoise, [('out', 'in_file')]),
(denoise, demean, [('out_file', 'in_file')]),
(demean, cleanup_wf, [('out', 'inputnode.in_file')]),
(bet, cleanup_wf, [('mask_file', 'inputnode.in_mask')]),
(cleanup_wf, applymsk, [('outputnode.out_file', 'in_file')]),
(bet, applymsk, [('mask_file', 'mask_file')]),
(applymsk, outputnode, [('out_file', 'fmap')]),
])
return workflow
def init_anat_preproc_wf(skull_strip_template, output_spaces, template, debug,
freesurfer, longitudinal, omp_nthreads, hires, reportlets_dir,
output_dir, num_t1w,
name='anat_preproc_wf'):
r"""
This workflow controls the anatomical preprocessing stages of FMRIPREP.
This includes:
- Creation of a structural template
- Skull-stripping and bias correction
- Tissue segmentation
- Normalization
- Surface reconstruction with FreeSurfer
.. workflow::
:graph2use: orig
:simple_form: yes
from fmriprep.workflows.anatomical import init_anat_preproc_wf
wf = init_anat_preproc_wf(omp_nthreads=1,
reportlets_dir='.',
output_dir='.',
template='MNI152NLin2009cAsym',
output_spaces=['T1w', 'fsnative',
'template', 'fsaverage5'],
skull_strip_template='OASIS',
freesurfer=True,
longitudinal=False,
debug=False,
hires=True,
num_t1w=1)
**Parameters**
skull_strip_template : str
Name of ANTs skull-stripping template ('OASIS' or 'NKI')
output_spaces : list
List of output spaces functional images are to be resampled to.
Some pipeline components will only be instantiated for some output spaces.
Valid spaces:
- T1w
- template
- fsnative
- fsaverage (or other pre-existing FreeSurfer templates)
template : str
Name of template targeted by `'template'` output space
debug : bool
Enable debugging outputs
freesurfer : bool
Enable FreeSurfer surface reconstruction (may increase runtime)
longitudinal : bool
Create unbiased structural template, regardless of number of inputs
(may increase runtime)
omp_nthreads : int
Maximum number of threads an individual process may use
hires : bool
Enable sub-millimeter preprocessing in FreeSurfer
reportlets_dir : str
Directory in which to save reportlets
output_dir : str
Directory in which to save derivatives
name : str, optional
Workflow name (default: anat_preproc_wf)
**Inputs**
t1w
List of T1-weighted structural images
t2w
List of T2-weighted structural images
subjects_dir
FreeSurfer SUBJECTS_DIR
**Outputs**
t1_preproc
Bias-corrected structural template, defining T1w space
t1_brain
Skull-stripped ``t1_preproc``
t1_mask
Mask of the skull-stripped template image
t1_seg
Segmentation of preprocessed structural image, including
gray-matter (GM), white-matter (WM) and cerebrospinal fluid (CSF)
t1_tpms
List of tissue probability maps in T1w space
t1_2_mni
T1w template, normalized to MNI space
t1_2_mni_forward_transform
ANTs-compatible affine-and-warp transform file
t1_2_mni_reverse_transform
ANTs-compatible affine-and-warp transform file (inverse)
mni_mask
Mask of skull-stripped template, in MNI space
mni_seg
Segmentation, resampled into MNI space
mni_tpms
List of tissue probability maps in MNI space
subjects_dir
FreeSurfer SUBJECTS_DIR
subject_id
FreeSurfer subject ID
t1_2_fsnative_forward_transform
LTA-style affine matrix translating from T1w to FreeSurfer-conformed subject space
t1_2_fsnative_reverse_transform
LTA-style affine matrix translating from FreeSurfer-conformed subject space to T1w
surfaces
GIFTI surfaces (gray/white boundary, midthickness, pial, inflated)
**Subworkflows**
* :py:func:`~fmriprep.workflows.anatomical.init_skullstrip_ants_wf`
* :py:func:`~fmriprep.workflows.anatomical.init_surface_recon_wf`
"""
workflow = pe.Workflow(name=name)
inputnode = pe.Node(
niu.IdentityInterface(fields=['t1w', 't2w', 'subjects_dir', 'subject_id']),
name='inputnode')
outputnode = pe.Node(niu.IdentityInterface(
fields=['t1_preproc', 't1_brain', 't1_mask', 't1_seg', 't1_tpms',
't1_2_mni', 't1_2_mni_forward_transform', 't1_2_mni_reverse_transform',
'mni_mask', 'mni_seg', 'mni_tpms',
'template_transforms',
'subjects_dir', 'subject_id', 't1_2_fsnative_forward_transform',
't1_2_fsnative_reverse_transform', 'surfaces']),
name='outputnode')
buffernode = pe.Node(niu.IdentityInterface(
fields=['t1_brain', 't1_mask']), name='buffernode')
anat_template_wf = init_anat_template_wf(longitudinal=longitudinal, omp_nthreads=omp_nthreads,
num_t1w=num_t1w)
# 3. Skull-stripping
# Bias field correction is handled in skull strip workflows.
skullstrip_ants_wf = init_skullstrip_ants_wf(name='skullstrip_ants_wf',
skull_strip_template=skull_strip_template,
debug=debug,
omp_nthreads=omp_nthreads)
workflow.connect([
(inputnode, anat_template_wf, [('t1w', 'inputnode.t1w')]),
(anat_template_wf, skullstrip_ants_wf, [('outputnode.t1_template', 'inputnode.in_file')]),
(skullstrip_ants_wf, outputnode, [('outputnode.bias_corrected', 't1_preproc')]),
(anat_template_wf, outputnode, [
('outputnode.template_transforms', 't1_template_transforms')]),
(buffernode, outputnode, [('t1_brain', 't1_brain'),
('t1_mask', 't1_mask')]),
])
# 4. Surface reconstruction
if freesurfer:
surface_recon_wf = init_surface_recon_wf(name='surface_recon_wf',
omp_nthreads=omp_nthreads, hires=hires)
applyrefined = pe.Node(fsl.ApplyMask(), name='applyrefined')
workflow.connect([
(inputnode, surface_recon_wf, [
('t2w', 'inputnode.t2w'),
('subjects_dir', 'inputnode.subjects_dir'),
('subject_id', 'inputnode.subject_id')]),
(anat_template_wf, surface_recon_wf, [('outputnode.t1_template', 'inputnode.t1w')]),
(skullstrip_ants_wf, surface_recon_wf, [
('outputnode.out_file', 'inputnode.skullstripped_t1'),
('outputnode.out_segs', 'inputnode.ants_segs'),
('outputnode.bias_corrected', 'inputnode.corrected_t1')]),
(skullstrip_ants_wf, applyrefined, [
('outputnode.bias_corrected', 'in_file')]),
(surface_recon_wf, applyrefined, [
('outputnode.out_brainmask', 'mask_file')]),
(surface_recon_wf, outputnode, [
('outputnode.subjects_dir', 'subjects_dir'),
('outputnode.subject_id', 'subject_id'),
('outputnode.t1_2_fsnative_forward_transform', 't1_2_fsnative_forward_transform'),
('outputnode.t1_2_fsnative_reverse_transform', 't1_2_fsnative_reverse_transform'),
('outputnode.surfaces', 'surfaces')]),
(applyrefined, buffernode, [('out_file', 't1_brain')]),
(surface_recon_wf, buffernode, [
('outputnode.out_brainmask', 't1_mask')]),
])
else:
workflow.connect([
(skullstrip_ants_wf, buffernode, [
('outputnode.out_file', 't1_brain'),
('outputnode.out_mask', 't1_mask')]),
])
# 5. Segmentation
t1_seg = pe.Node(fsl.FAST(segments=True, no_bias=True, probability_maps=True),
name='t1_seg', mem_gb=3)
workflow.connect([
(buffernode, t1_seg, [('t1_brain', 'in_files')]),
(t1_seg, outputnode, [('tissue_class_map', 't1_seg'),
('probability_maps', 't1_tpms')]),
])
# 6. Spatial normalization (T1w to MNI registration)
t1_2_mni = pe.Node(
RobustMNINormalizationRPT(
float=True,
generate_report=True,
flavor='testing' if debug else 'precise',
),
name='t1_2_mni',
n_procs=omp_nthreads,
mem_gb=2
)
# Resample the brain mask and the tissue probability maps into mni space
mni_mask = pe.Node(
ApplyTransforms(dimension=3, default_value=0, float=True,
interpolation='NearestNeighbor'),
name='mni_mask'
)
mni_seg = pe.Node(
ApplyTransforms(dimension=3, default_value=0, float=True,
interpolation='NearestNeighbor'),
name='mni_seg'
)
mni_tpms = pe.MapNode(
ApplyTransforms(dimension=3, default_value=0, float=True,
interpolation='Linear'),
iterfield=['input_image'],
name='mni_tpms'
)
if 'template' in output_spaces:
template_str = nid.TEMPLATE_MAP[template]
ref_img = op.join(nid.get_dataset(template_str), '1mm_T1.nii.gz')
t1_2_mni.inputs.template = template_str
mni_mask.inputs.reference_image = ref_img
mni_seg.inputs.reference_image = ref_img
mni_tpms.inputs.reference_image = ref_img
workflow.connect([
(skullstrip_ants_wf, t1_2_mni, [('outputnode.bias_corrected', 'moving_image')]),
(buffernode, t1_2_mni, [('t1_mask', 'moving_mask')]),
(buffernode, mni_mask, [('t1_mask', 'input_image')]),
(t1_2_mni, mni_mask, [('composite_transform', 'transforms')]),
(t1_seg, mni_seg, [('tissue_class_map', 'input_image')]),
(t1_2_mni, mni_seg, [('composite_transform', 'transforms')]),
(t1_seg, mni_tpms, [('probability_maps', 'input_image')]),
(t1_2_mni, mni_tpms, [('composite_transform', 'transforms')]),
(t1_2_mni, outputnode, [
('warped_image', 't1_2_mni'),
('composite_transform', 't1_2_mni_forward_transform'),
('inverse_composite_transform', 't1_2_mni_reverse_transform')]),
(mni_mask, outputnode, [('output_image', 'mni_mask')]),
(mni_seg, outputnode, [('output_image', 'mni_seg')]),
(mni_tpms, outputnode, [('output_image', 'mni_tpms')]),
])
seg2msks = pe.Node(niu.Function(function=_seg2msks), name='seg2msks')
seg_rpt = pe.Node(ROIsPlot(colors=['r', 'magenta', 'b', 'g']), name='seg_rpt')
anat_reports_wf = init_anat_reports_wf(
reportlets_dir=reportlets_dir, output_spaces=output_spaces, template=template,
freesurfer=freesurfer)
workflow.connect([
(inputnode, anat_reports_wf, [
(('t1w', fix_multi_T1w_source_name), 'inputnode.source_file')]),
(anat_template_wf, anat_reports_wf, [
('outputnode.out_report', 'inputnode.t1_conform_report')]),
(anat_template_wf, seg_rpt, [
('outputnode.t1_template', 'in_file')]),
(t1_seg, seg2msks, [('tissue_class_map', 'in_file')]),
(seg2msks, seg_rpt, [('out', 'in_rois')]),
(outputnode, seg_rpt, [('t1_mask', 'in_mask')]),
(seg_rpt, anat_reports_wf, [('out_report', 'inputnode.seg_report')]),
])
if freesurfer:
workflow.connect([
(surface_recon_wf, anat_reports_wf, [
('outputnode.out_report', 'inputnode.recon_report')])
])
if 'template' in output_spaces:
workflow.connect([
(t1_2_mni, anat_reports_wf, [('out_report', 'inputnode.t1_2_mni_report')]),
])
anat_derivatives_wf = init_anat_derivatives_wf(output_dir=output_dir,
output_spaces=output_spaces,
template=template,
freesurfer=freesurfer)
workflow.connect([
(anat_template_wf, anat_derivatives_wf, [
('outputnode.t1w_valid_list', 'inputnode.source_files')]),
(outputnode, anat_derivatives_wf, [
('t1_template_transforms', 'inputnode.t1_template_transforms'),
('t1_preproc', 'inputnode.t1_preproc'),
('t1_mask', 'inputnode.t1_mask'),
('t1_seg', 'inputnode.t1_seg'),
('t1_tpms', 'inputnode.t1_tpms'),
('t1_2_mni_forward_transform', 'inputnode.t1_2_mni_forward_transform'),
('t1_2_mni_reverse_transform', 'inputnode.t1_2_mni_reverse_transform'),
('t1_2_mni', 'inputnode.t1_2_mni'),
('mni_mask', 'inputnode.mni_mask'),
('mni_seg', 'inputnode.mni_seg'),
('mni_tpms', 'inputnode.mni_tpms'),
('t1_2_fsnative_forward_transform', 'inputnode.t1_2_fsnative_forward_transform'),
('surfaces', 'inputnode.surfaces'),
]),
])
return workflow
