def epi_mni_align(name='SpatialNormalization', ants_nthreads=6, testing=False, resolution=2):
"""
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.
"""
from nipype.interfaces.ants import ApplyTransforms, N4BiasFieldCorrection
from niworkflows.data import get_mni_icbm152_nlin_asym_09c as get_template
from niworkflows.interfaces.registration import RobustMNINormalizationRPT as RobustMNINormalization
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(N4BiasFieldCorrection(dimension=3), name='SharpenEPI')
# Mask T2 template image
brainmask = pe.Node(fsl.ApplyMask(
in_file=op.join(mni_template, '%dmm_T2.nii.gz' % resolution),
mask_file=op.join(mni_template, '%dmm_brainmask.nii.gz' % resolution)),
name='MNIApplyMask')
norm = pe.Node(RobustMNINormalization(
num_threads=ants_nthreads, template='mni_icbm152_nlin_asym_09c',
testing=testing, moving='EPI', generate_report=True),
name='EPI2MNI')
# Warp segmentation into EPI space
invt = pe.Node(ApplyTransforms(
input_image=op.join(mni_template, '%dmm_parc.nii.gz' % resolution),
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')]),
(brainmask, norm, [('out_file', 'reference_image')]),
(epimask, norm, [('out_file', 'moving_image')]),
(norm, invt, [
('reverse_transforms', 'transforms'),
('reverse_invert_flags', 'invert_transform_flags')]),
(invt, outputnode, [('output_image', 'epi_parc')]),
(norm, outputnode, [('warped_image', 'epi_mni'),
('out_report', 'report')]),
])
return workflow
def init_bold_mni_trans_wf(template,
freesurfer,
mem_gb,
omp_nthreads,
name='bold_mni_trans_wf',
template_out_grid='2mm',
use_compression=True,
use_fieldwarp=False):
"""
This workflow samples functional images to the MNI template in a "single shot"
from the original BOLD series.
.. workflow::
:graph2use: colored
:simple_form: yes
from fmriprep.workflows.bold import init_bold_mni_trans_wf
wf = init_bold_mni_trans_wf(template='MNI152NLin2009cAsym',
freesurfer=True,
mem_gb=3,
omp_nthreads=1,
template_out_grid='native')
**Parameters**
template : str
Name of template targeted by ``template`` output space
freesurfer : bool
Enable sampling of FreeSurfer files
mem_gb : float
Size of BOLD file in GB
omp_nthreads : int
Maximum number of threads an individual process may use
name : str
Name of workflow (default: ``bold_mni_trans_wf``)
template_out_grid : str
Keyword ('native', '1mm' or '2mm') or path of custom reference
image for normalization.
use_compression : bool
Save registered BOLD series as ``.nii.gz``
use_fieldwarp : bool
Include SDC warp in single-shot transform from BOLD to MNI
**Inputs**
itk_bold_to_t1
Affine transform from ``ref_bold_brain`` to T1 space (ITK format)
t1_2_mni_forward_transform
ANTs-compatible affine-and-warp transform file
bold_split
Individual 3D volumes, not motion corrected
bold_mask
Skull-stripping mask of reference image
bold_aseg
FreeSurfer's ``aseg.mgz`` atlas projected into the T1w reference
(only if ``recon-all`` was run).
bold_aparc
FreeSurfer's ``aparc+aseg.mgz`` atlas projected into the T1w reference
(only if ``recon-all`` was run).
name_source
BOLD series NIfTI file
Used to recover original information lost during processing
hmc_xforms
List of affine transforms aligning each volume to ``ref_image`` in ITK format
fieldwarp
a :abbr:`DFM (displacements field map)` in ITK format
**Outputs**
bold_mni
BOLD series, resampled to template space
bold_mni_ref
Reference, contrast-enhanced summary of the BOLD series, resampled to template space
bold_mask_mni
BOLD series mask in template space
bold_aseg_mni
FreeSurfer's ``aseg.mgz`` atlas, in template space at the BOLD resolution
(only if ``recon-all`` was run)
bold_aparc_mni
FreeSurfer's ``aparc+aseg.mgz`` atlas, in template space at the BOLD resolution
(only if ``recon-all`` was run)
"""
workflow = Workflow(name=name)
workflow.__desc__ = """\
The BOLD time-series were resampled to {tpl} standard space,
generating a *preprocessed BOLD run in {tpl} space*.
""".format(tpl=template)
inputnode = pe.Node(niu.IdentityInterface(fields=[
'itk_bold_to_t1', 't1_2_mni_forward_transform', 'name_source',
'bold_split', 'bold_mask', 'bold_aseg', 'bold_aparc', 'hmc_xforms',
'fieldwarp'
]),
name='inputnode')
outputnode = pe.Node(niu.IdentityInterface(fields=[
'bold_mni', 'bold_mni_ref', 'bold_mask_mni', 'bold_aseg_mni',
'bold_aparc_mni'
]),
name='outputnode')
def _aslist(in_value):
if isinstance(in_value, list):
return in_value
return [in_value]
gen_ref = pe.Node(GenerateSamplingReference(), name='gen_ref',
mem_gb=0.3) # 256x256x256 * 64 / 8 ~ 150MB)
# Account for template aliases
template_name = TEMPLATE_ALIASES.get(template, template)
# Template path
template_dir = get_template(template_name)
gen_ref.inputs.fixed_image = str(
template_dir / ('tpl-%s_space-MNI_res-01_T1w.nii.gz' % template_name))
mask_mni_tfm = pe.Node(ApplyTransforms(interpolation='MultiLabel',
float=True),
name='mask_mni_tfm',
mem_gb=1)
# Write corrected file in the designated output dir
mask_merge_tfms = pe.Node(niu.Merge(2),
name='mask_merge_tfms',
run_without_submitting=True,
mem_gb=DEFAULT_MEMORY_MIN_GB)
workflow.connect([
(inputnode, gen_ref, [(('bold_split', _first), 'moving_image')]),
(inputnode, mask_mni_tfm, [('bold_mask', 'input_image')]),
(inputnode, mask_merge_tfms, [('t1_2_mni_forward_transform', 'in1'),
(('itk_bold_to_t1', _aslist), 'in2')]),
(mask_merge_tfms, mask_mni_tfm, [('out', 'transforms')]),
(mask_mni_tfm, outputnode, [('output_image', 'bold_mask_mni')]),
])
nxforms = 4 if use_fieldwarp else 3
merge_xforms = pe.Node(niu.Merge(nxforms),
name='merge_xforms',
run_without_submitting=True,
mem_gb=DEFAULT_MEMORY_MIN_GB)
workflow.connect([(inputnode, merge_xforms, [('hmc_xforms',
'in%d' % nxforms)])])
if use_fieldwarp:
workflow.connect([(inputnode, merge_xforms, [('fieldwarp', 'in3')])])
bold_to_mni_transform = pe.Node(MultiApplyTransforms(
interpolation="LanczosWindowedSinc", float=True, copy_dtype=True),
name='bold_to_mni_transform',
mem_gb=mem_gb * 3 * omp_nthreads,
n_procs=omp_nthreads)
merge = pe.Node(Merge(compress=use_compression),
name='merge',
mem_gb=mem_gb * 3)
# Generate a reference on the target T1w space
gen_final_ref = init_bold_reference_wf(omp_nthreads=omp_nthreads,
pre_mask=True)
workflow.connect([
(inputnode, merge_xforms, [('t1_2_mni_forward_transform', 'in1'),
(('itk_bold_to_t1', _aslist), 'in2')]),
(merge_xforms, bold_to_mni_transform, [('out', 'transforms')]),
(inputnode, merge, [('name_source', 'header_source')]),
(inputnode, bold_to_mni_transform, [('bold_split', 'input_image')]),
(bold_to_mni_transform, merge, [('out_files', 'in_files')]),
(merge, gen_final_ref, [('out_file', 'inputnode.bold_file')]),
(mask_mni_tfm, gen_final_ref, [('output_image', 'inputnode.bold_mask')
]),
(merge, outputnode, [('out_file', 'bold_mni')]),
(gen_final_ref, outputnode, [('outputnode.ref_image', 'bold_mni_ref')
]),
])
if template_out_grid == 'native':
workflow.connect([
(gen_ref, mask_mni_tfm, [('out_file', 'reference_image')]),
(gen_ref, bold_to_mni_transform, [('out_file', 'reference_image')
]),
])
elif template_out_grid in ['1mm', '2mm']:
res = int(template_out_grid[0])
mask_mni_tfm.inputs.reference_image = str(
template_dir / ('tpl-%s_space-MNI_res-%02d_brainmask.nii.gz' %
(template_name, res)))
bold_to_mni_transform.inputs.reference_image = str(
template_dir / ('tpl-%s_space-MNI_res-%02d_T1w.nii.gz' %
(template_name, res)))
else:
mask_mni_tfm.inputs.reference_image = template_out_grid
bold_to_mni_transform.inputs.reference_image = template_out_grid
if freesurfer:
# Sample the parcellation files to functional space
aseg_mni_tfm = pe.Node(ApplyTransforms(interpolation='MultiLabel',
float=True),
name='aseg_mni_tfm',
mem_gb=1)
aparc_mni_tfm = pe.Node(ApplyTransforms(interpolation='MultiLabel',
float=True),
name='aparc_mni_tfm',
mem_gb=1)
workflow.connect([
(inputnode, aseg_mni_tfm, [('bold_aseg', 'input_image'),
('t1_2_mni_forward_transform',
'transforms')]),
(inputnode, aparc_mni_tfm, [('bold_aparc', 'input_image'),
('t1_2_mni_forward_transform',
'transforms')]),
(aseg_mni_tfm, outputnode, [('output_image', 'bold_aseg_mni')]),
(aparc_mni_tfm, outputnode, [('output_image', 'bold_aparc_mni')]),
])
if template_out_grid == 'native':
workflow.connect([
(gen_ref, aseg_mni_tfm, [('out_file', 'reference_image')]),
(gen_ref, aparc_mni_tfm, [('out_file', 'reference_image')]),
])
elif template_out_grid in ['1mm', '2mm']:
res = int(template_out_grid[0])
aseg_mni_tfm.inputs.reference_image = str(
template_dir / ('tpl-%s_space-MNI_res-%02d_brainmask.nii.gz' %
(template_name, res)))
aparc_mni_tfm.inputs.reference_image = str(
template_dir / ('tpl-%s_space-MNI_res-%02d_T1w.nii.gz' %
(template_name, res)))
else:
aseg_mni_tfm.inputs.reference_image = template_out_grid
aparc_mni_tfm.inputs.reference_image = template_out_grid
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=str(Path(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_ica_aroma_wf(template,
metadata,
mem_gb,
omp_nthreads,
name='ica_aroma_wf',
susan_fwhm=6.0,
ignore_aroma_err=False,
aroma_melodic_dim=-200,
use_fieldwarp=True):
"""
This workflow wraps `ICA-AROMA`_ to identify and remove motion-related
independent components from a BOLD time series.
The following steps are performed:
#. Remove non-steady state volumes from the bold series.
#. Smooth data using FSL `susan`, with a kernel width FWHM=6.0mm.
#. Run FSL `melodic` outside of ICA-AROMA to generate the report
#. Run ICA-AROMA
#. Aggregate identified motion components (aggressive) to TSV
#. Return ``classified_motion_ICs`` and ``melodic_mix`` for user to complete
non-aggressive denoising in T1w space
#. Calculate ICA-AROMA-identified noise components
(columns named ``AROMAAggrCompXX``)
Additionally, non-aggressive denoising is performed on the BOLD series
resampled into MNI space.
There is a current discussion on whether other confounds should be extracted
before or after denoising `here <http://nbviewer.jupyter.org/github/poldracklab/\
fmriprep-notebooks/blob/922e436429b879271fa13e76767a6e73443e74d9/issue-817_\
aroma_confounds.ipynb>`__.
.. workflow::
:graph2use: orig
:simple_form: yes
from fmriprep.workflows.bold.confounds import init_ica_aroma_wf
wf = init_ica_aroma_wf(template='MNI152NLin2009cAsym',
metadata={'RepetitionTime': 1.0},
mem_gb=3,
omp_nthreads=1)
**Parameters**
template : str
Spatial normalization template used as target when that
registration step was previously calculated with
:py:func:`~fmriprep.workflows.bold.registration.init_bold_reg_wf`.
The template must be one of the MNI templates (fMRIPrep uses
``MNI152NLin2009cAsym`` by default).
metadata : dict
BIDS metadata for BOLD file
mem_gb : float
Size of BOLD file in GB
omp_nthreads : int
Maximum number of threads an individual process may use
name : str
Name of workflow (default: ``bold_mni_trans_wf``)
susan_fwhm : float
Kernel width (FWHM in mm) for the smoothing step with
FSL ``susan`` (default: 6.0mm)
use_fieldwarp : bool
Include SDC warp in single-shot transform from BOLD to MNI
ignore_aroma_err : bool
Do not fail on ICA-AROMA errors
aroma_melodic_dim: int
Set the dimensionality of the MELODIC ICA decomposition.
Negative numbers set a maximum on automatic dimensionality estimation.
Positive numbers set an exact number of components to extract.
(default: -200, i.e., estimate <=200 components)
**Inputs**
itk_bold_to_t1
Affine transform from ``ref_bold_brain`` to T1 space (ITK format)
t1_2_mni_forward_transform
ANTs-compatible affine-and-warp transform file
name_source
BOLD series NIfTI file
Used to recover original information lost during processing
skip_vols
number of non steady state volumes
bold_split
Individual 3D BOLD volumes, not motion corrected
bold_mask
BOLD series mask in template space
hmc_xforms
List of affine transforms aligning each volume to ``ref_image`` in ITK format
fieldwarp
a :abbr:`DFM (displacements field map)` in ITK format
movpar_file
SPM-formatted motion parameters file
**Outputs**
aroma_confounds
TSV of confounds identified as noise by ICA-AROMA
aroma_noise_ics
CSV of noise components identified by ICA-AROMA
melodic_mix
FSL MELODIC mixing matrix
nonaggr_denoised_file
BOLD series with non-aggressive ICA-AROMA denoising applied
.. _ICA-AROMA: https://github.com/maartenmennes/ICA-AROMA
"""
workflow = Workflow(name=name)
workflow.__postdesc__ = """\
Automatic removal of motion artifacts using independent component analysis
[ICA-AROMA, @aroma] was performed on the *preprocessed BOLD on MNI space*
time-series after removal of non-steady state volumes and spatial smoothing
with an isotropic, Gaussian kernel of 6mm FWHM (full-width half-maximum).
Corresponding "non-aggresively" denoised runs were produced after such
smoothing.
Additionally, the "aggressive" noise-regressors were collected and placed
in the corresponding confounds file.
"""
inputnode = pe.Node(niu.IdentityInterface(fields=[
'itk_bold_to_t1', 't1_2_mni_forward_transform', 'name_source',
'skip_vols', 'bold_split', 'bold_mask', 'hmc_xforms', 'fieldwarp',
'movpar_file'
]),
name='inputnode')
outputnode = pe.Node(niu.IdentityInterface(fields=[
'aroma_confounds', 'aroma_noise_ics', 'melodic_mix',
'nonaggr_denoised_file'
]),
name='outputnode')
bold_mni_trans_wf = init_bold_mni_trans_wf(
template=template,
mem_gb=mem_gb,
omp_nthreads=omp_nthreads,
template_out_grid=str(
get_template('MNI152Lin') /
'tpl-MNI152Lin_space-MNI_res-02_T1w.nii.gz'),
use_compression=False,
use_fieldwarp=use_fieldwarp,
name='bold_mni_trans_wf')
bold_mni_trans_wf.__desc__ = None
rm_non_steady_state = pe.Node(niu.Function(function=_remove_volumes,
output_names=['bold_cut']),
name='rm_nonsteady')
calc_median_val = pe.Node(fsl.ImageStats(op_string='-k %s -p 50'),
name='calc_median_val')
calc_bold_mean = pe.Node(fsl.MeanImage(), name='calc_bold_mean')
def _getusans_func(image, thresh):
return [tuple([image, thresh])]
getusans = pe.Node(niu.Function(function=_getusans_func,
output_names=['usans']),
name='getusans',
mem_gb=0.01)
smooth = pe.Node(fsl.SUSAN(fwhm=susan_fwhm), name='smooth')
# melodic node
melodic = pe.Node(fsl.MELODIC(no_bet=True,
tr_sec=float(metadata['RepetitionTime']),
mm_thresh=0.5,
out_stats=True,
dim=aroma_melodic_dim),
name="melodic")
# ica_aroma node
ica_aroma = pe.Node(ICA_AROMARPT(denoise_type='nonaggr',
generate_report=True,
TR=metadata['RepetitionTime']),
name='ica_aroma')
add_non_steady_state = pe.Node(niu.Function(function=_add_volumes,
output_names=['bold_add']),
name='add_nonsteady')
# extract the confound ICs from the results
ica_aroma_confound_extraction = pe.Node(
ICAConfounds(ignore_aroma_err=ignore_aroma_err),
name='ica_aroma_confound_extraction')
ds_report_ica_aroma = pe.Node(DerivativesDataSink(suffix='ica_aroma'),
name='ds_report_ica_aroma',
run_without_submitting=True,
mem_gb=DEFAULT_MEMORY_MIN_GB)
def _getbtthresh(medianval):
return 0.75 * medianval
# connect the nodes
workflow.connect([
(inputnode, bold_mni_trans_wf,
[('name_source', 'inputnode.name_source'),
('bold_split', 'inputnode.bold_split'),
('bold_mask', 'inputnode.bold_mask'),
('hmc_xforms', 'inputnode.hmc_xforms'),
('itk_bold_to_t1', 'inputnode.itk_bold_to_t1'),
('t1_2_mni_forward_transform',
'inputnode.t1_2_mni_forward_transform'),
('fieldwarp', 'inputnode.fieldwarp')]),
(inputnode, ica_aroma, [('movpar_file', 'motion_parameters')]),
(inputnode, rm_non_steady_state, [('skip_vols', 'skip_vols')]),
(bold_mni_trans_wf, rm_non_steady_state, [('outputnode.bold_mni',
'bold_file')]),
(bold_mni_trans_wf, calc_median_val, [('outputnode.bold_mask_mni',
'mask_file')]),
(rm_non_steady_state, calc_median_val, [('bold_cut', 'in_file')]),
(rm_non_steady_state, calc_bold_mean, [('bold_cut', 'in_file')]),
(calc_bold_mean, getusans, [('out_file', 'image')]),
(calc_median_val, getusans, [('out_stat', 'thresh')]),
# Connect input nodes to complete smoothing
(rm_non_steady_state, smooth, [('bold_cut', 'in_file')]),
(getusans, smooth, [('usans', 'usans')]),
(calc_median_val, smooth, [(('out_stat', _getbtthresh),
'brightness_threshold')]),
# connect smooth to melodic
(smooth, melodic, [('smoothed_file', 'in_files')]),
(bold_mni_trans_wf, melodic, [('outputnode.bold_mask_mni', 'mask')]),
# connect nodes to ICA-AROMA
(smooth, ica_aroma, [('smoothed_file', 'in_file')]),
(bold_mni_trans_wf, ica_aroma, [('outputnode.bold_mask_mni',
'report_mask'),
('outputnode.bold_mask_mni', 'mask')]),
(melodic, ica_aroma, [('out_dir', 'melodic_dir')]),
# generate tsvs from ICA-AROMA
(ica_aroma, ica_aroma_confound_extraction, [('out_dir', 'in_directory')
]),
(inputnode, ica_aroma_confound_extraction, [('skip_vols', 'skip_vols')
]),
# output for processing and reporting
(ica_aroma_confound_extraction,
outputnode, [('aroma_confounds', 'aroma_confounds'),
('aroma_noise_ics', 'aroma_noise_ics'),
('melodic_mix', 'melodic_mix')]),
# TODO change melodic report to reflect noise and non-noise components
(ica_aroma, add_non_steady_state, [('nonaggr_denoised_file',
'bold_cut_file')]),
(bold_mni_trans_wf, add_non_steady_state, [('outputnode.bold_mni',
'bold_file')]),
(inputnode, add_non_steady_state, [('skip_vols', 'skip_vols')]),
(add_non_steady_state, outputnode, [('bold_add',
'nonaggr_denoised_file')]),
(ica_aroma, ds_report_ica_aroma, [('out_report', 'in_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_carpetplot_wf(mem_gb, metadata, name="bold_carpet_wf"):
"""
Resamples the MNI parcellation (ad-hoc parcellation derived from the
Harvard-Oxford template and others).
**Parameters**
mem_gb : float
Size of BOLD file in GB - please note that this size
should be calculated after resamplings that may extend
the FoV
metadata : dict
BIDS metadata for BOLD file
name : str
Name of workflow (default: ``bold_carpet_wf``)
**Inputs**
bold
BOLD image, after the prescribed corrections (STC, HMC and SDC)
when available.
bold_mask
BOLD series mask
confounds_file
TSV of all aggregated confounds
t1_bold_xform
Affine matrix that maps the T1w space into alignment with
the native BOLD space
t1_2_mni_reverse_transform
ANTs-compatible affine-and-warp transform file
**Outputs**
out_carpetplot
Path of the generated SVG file
"""
inputnode = pe.Node(niu.IdentityInterface(fields=[
'bold', 'bold_mask', 'confounds_file', 't1_bold_xform',
't1_2_mni_reverse_transform'
]),
name='inputnode')
outputnode = pe.Node(niu.IdentityInterface(fields=['out_carpetplot']),
name='outputnode')
# List transforms
mrg_xfms = pe.Node(niu.Merge(2), name='mrg_xfms')
# Warp segmentation into EPI space
resample_parc = pe.Node(ApplyTransforms(
float=True,
input_image=str(
get_template('MNI152NLin2009cAsym') /
'tpl-MNI152NLin2009cAsym_space-MNI_res-01_label-carpet_atlas.nii.gz'
),
dimension=3,
default_value=0,
interpolation='MultiLabel'),
name='resample_parc')
# Carpetplot and confounds plot
conf_plot = pe.Node(FMRISummary(tr=metadata['RepetitionTime'],
confounds_list=[
('global_signal', None, 'GS'),
('csf', None, 'GSCSF'),
('white_matter', None, 'GSWM'),
('std_dvars', None, 'DVARS'),
('framewise_displacement', 'mm', 'FD')
]),
name='conf_plot',
mem_gb=mem_gb)
ds_report_bold_conf = pe.Node(DerivativesDataSink(suffix='carpetplot'),
name='ds_report_bold_conf',
run_without_submitting=True,
mem_gb=DEFAULT_MEMORY_MIN_GB)
workflow = Workflow(name=name)
workflow.connect([
(inputnode, mrg_xfms, [('t1_bold_xform', 'in1'),
('t1_2_mni_reverse_transform', 'in2')]),
(inputnode, resample_parc, [('bold_mask', 'reference_image')]),
(mrg_xfms, resample_parc, [('out', 'transforms')]),
# Carpetplot
(inputnode, conf_plot, [('bold', 'in_func'), ('bold_mask', 'in_mask'),
('confounds_file', 'confounds_file')]),
(resample_parc, conf_plot, [('output_image', 'in_segm')]),
(conf_plot, ds_report_bold_conf, [('out_file', 'in_file')]),
(conf_plot, outputnode, [('out_file', 'out_carpetplot')]),
])
return workflow
def init_ica_aroma_wf(template, metadata, mem_gb, omp_nthreads,
name='ica_aroma_wf',
susan_fwhm=6.0,
ignore_aroma_err=False,
aroma_melodic_dim=-200,
use_fieldwarp=True):
"""
This workflow wraps `ICA-AROMA`_ to identify and remove motion-related
independent components from a BOLD time series.
The following steps are performed:
#. Remove non-steady state volumes from the bold series.
#. Smooth data using FSL `susan`, with a kernel width FWHM=6.0mm.
#. Run FSL `melodic` outside of ICA-AROMA to generate the report
#. Run ICA-AROMA
#. Aggregate identified motion components (aggressive) to TSV
#. Return ``classified_motion_ICs`` and ``melodic_mix`` for user to complete
non-aggressive denoising in T1w space
#. Calculate ICA-AROMA-identified noise components
(columns named ``AROMAAggrCompXX``)
Additionally, non-aggressive denoising is performed on the BOLD series
resampled into MNI space.
There is a current discussion on whether other confounds should be extracted
before or after denoising `here <http://nbviewer.jupyter.org/github/poldracklab/\
fmriprep-notebooks/blob/922e436429b879271fa13e76767a6e73443e74d9/issue-817_\
aroma_confounds.ipynb>`__.
.. workflow::
:graph2use: orig
:simple_form: yes
from fmriprep.workflows.bold.confounds import init_ica_aroma_wf
wf = init_ica_aroma_wf(template='MNI152NLin2009cAsym',
metadata={'RepetitionTime': 1.0},
mem_gb=3,
omp_nthreads=1)
**Parameters**
template : str
Spatial normalization template used as target when that
registration step was previously calculated with
:py:func:`~fmriprep.workflows.bold.registration.init_bold_reg_wf`.
The template must be one of the MNI templates (fMRIPrep uses
``MNI152NLin2009cAsym`` by default).
metadata : dict
BIDS metadata for BOLD file
mem_gb : float
Size of BOLD file in GB
omp_nthreads : int
Maximum number of threads an individual process may use
name : str
Name of workflow (default: ``bold_mni_trans_wf``)
susan_fwhm : float
Kernel width (FWHM in mm) for the smoothing step with
FSL ``susan`` (default: 6.0mm)
use_fieldwarp : bool
Include SDC warp in single-shot transform from BOLD to MNI
ignore_aroma_err : bool
Do not fail on ICA-AROMA errors
aroma_melodic_dim: int
Set the dimensionality of the MELODIC ICA decomposition.
Negative numbers set a maximum on automatic dimensionality estimation.
Positive numbers set an exact number of components to extract.
(default: -200, i.e., estimate <=200 components)
**Inputs**
itk_bold_to_t1
Affine transform from ``ref_bold_brain`` to T1 space (ITK format)
t1_2_mni_forward_transform
ANTs-compatible affine-and-warp transform file
name_source
BOLD series NIfTI file
Used to recover original information lost during processing
skip_vols
number of non steady state volumes
bold_split
Individual 3D BOLD volumes, not motion corrected
bold_mask
BOLD series mask in template space
hmc_xforms
List of affine transforms aligning each volume to ``ref_image`` in ITK format
fieldwarp
a :abbr:`DFM (displacements field map)` in ITK format
movpar_file
SPM-formatted motion parameters file
**Outputs**
aroma_confounds
TSV of confounds identified as noise by ICA-AROMA
aroma_noise_ics
CSV of noise components identified by ICA-AROMA
melodic_mix
FSL MELODIC mixing matrix
nonaggr_denoised_file
BOLD series with non-aggressive ICA-AROMA denoising applied
.. _ICA-AROMA: https://github.com/maartenmennes/ICA-AROMA
"""
workflow = Workflow(name=name)
workflow.__postdesc__ = """\
Automatic removal of motion artifacts using independent component analysis
[ICA-AROMA, @aroma] was performed on the *preprocessed BOLD on MNI space*
time-series after removal of non-steady state volumes and spatial smoothing
with an isotropic, Gaussian kernel of 6mm FWHM (full-width half-maximum).
Corresponding "non-aggresively" denoised runs were produced after such
smoothing.
Additionally, the "aggressive" noise-regressors were collected and placed
in the corresponding confounds file.
"""
inputnode = pe.Node(niu.IdentityInterface(
fields=[
'itk_bold_to_t1',
't1_2_mni_forward_transform',
'name_source',
'skip_vols',
'bold_split',
'bold_mask',
'hmc_xforms',
'fieldwarp',
'movpar_file']), name='inputnode')
outputnode = pe.Node(niu.IdentityInterface(
fields=['aroma_confounds', 'aroma_noise_ics', 'melodic_mix',
'nonaggr_denoised_file']), name='outputnode')
bold_mni_trans_wf = init_bold_mni_trans_wf(
template=template,
freesurfer=False,
mem_gb=mem_gb,
omp_nthreads=omp_nthreads,
template_out_grid=str(
get_template('MNI152Lin') / 'tpl-MNI152Lin_space-MNI_res-02_T1w.nii.gz'),
use_compression=False,
use_fieldwarp=use_fieldwarp,
name='bold_mni_trans_wf'
)
bold_mni_trans_wf.__desc__ = None
rm_non_steady_state = pe.Node(niu.Function(function=_remove_volumes,
output_names=['bold_cut']),
name='rm_nonsteady')
calc_median_val = pe.Node(fsl.ImageStats(op_string='-k %s -p 50'), name='calc_median_val')
calc_bold_mean = pe.Node(fsl.MeanImage(), name='calc_bold_mean')
def _getusans_func(image, thresh):
return [tuple([image, thresh])]
getusans = pe.Node(niu.Function(function=_getusans_func, output_names=['usans']),
name='getusans', mem_gb=0.01)
smooth = pe.Node(fsl.SUSAN(fwhm=susan_fwhm), name='smooth')
# melodic node
melodic = pe.Node(fsl.MELODIC(
no_bet=True, tr_sec=float(metadata['RepetitionTime']), mm_thresh=0.5, out_stats=True,
dim=aroma_melodic_dim), name="melodic")
# ica_aroma node
ica_aroma = pe.Node(ICA_AROMARPT(
denoise_type='nonaggr', generate_report=True, TR=metadata['RepetitionTime']),
name='ica_aroma')
add_non_steady_state = pe.Node(niu.Function(function=_add_volumes,
output_names=['bold_add']),
name='add_nonsteady')
# extract the confound ICs from the results
ica_aroma_confound_extraction = pe.Node(ICAConfounds(ignore_aroma_err=ignore_aroma_err),
name='ica_aroma_confound_extraction')
ds_report_ica_aroma = pe.Node(
DerivativesDataSink(suffix='ica_aroma'),
name='ds_report_ica_aroma', run_without_submitting=True,
mem_gb=DEFAULT_MEMORY_MIN_GB)
def _getbtthresh(medianval):
return 0.75 * medianval
# connect the nodes
workflow.connect([
(inputnode, bold_mni_trans_wf, [
('name_source', 'inputnode.name_source'),
('bold_split', 'inputnode.bold_split'),
('bold_mask', 'inputnode.bold_mask'),
('hmc_xforms', 'inputnode.hmc_xforms'),
('itk_bold_to_t1', 'inputnode.itk_bold_to_t1'),
('t1_2_mni_forward_transform', 'inputnode.t1_2_mni_forward_transform'),
('fieldwarp', 'inputnode.fieldwarp')]),
(inputnode, ica_aroma, [('movpar_file', 'motion_parameters')]),
(inputnode, rm_non_steady_state, [
('skip_vols', 'skip_vols')]),
(bold_mni_trans_wf, rm_non_steady_state, [
('outputnode.bold_mni', 'bold_file')]),
(bold_mni_trans_wf, calc_median_val, [
('outputnode.bold_mask_mni', 'mask_file')]),
(rm_non_steady_state, calc_median_val, [
('bold_cut', 'in_file')]),
(rm_non_steady_state, calc_bold_mean, [
('bold_cut', 'in_file')]),
(calc_bold_mean, getusans, [('out_file', 'image')]),
(calc_median_val, getusans, [('out_stat', 'thresh')]),
# Connect input nodes to complete smoothing
(rm_non_steady_state, smooth, [
('bold_cut', 'in_file')]),
(getusans, smooth, [('usans', 'usans')]),
(calc_median_val, smooth, [(('out_stat', _getbtthresh), 'brightness_threshold')]),
# connect smooth to melodic
(smooth, melodic, [('smoothed_file', 'in_files')]),
(bold_mni_trans_wf, melodic, [
('outputnode.bold_mask_mni', 'mask')]),
# connect nodes to ICA-AROMA
(smooth, ica_aroma, [('smoothed_file', 'in_file')]),
(bold_mni_trans_wf, ica_aroma, [
('outputnode.bold_mask_mni', 'report_mask'),
('outputnode.bold_mask_mni', 'mask')]),
(melodic, ica_aroma, [('out_dir', 'melodic_dir')]),
# generate tsvs from ICA-AROMA
(ica_aroma, ica_aroma_confound_extraction, [('out_dir', 'in_directory')]),
(inputnode, ica_aroma_confound_extraction, [
('skip_vols', 'skip_vols')]),
# output for processing and reporting
(ica_aroma_confound_extraction, outputnode, [('aroma_confounds', 'aroma_confounds'),
('aroma_noise_ics', 'aroma_noise_ics'),
('melodic_mix', 'melodic_mix')]),
# TODO change melodic report to reflect noise and non-noise components
(ica_aroma, add_non_steady_state, [
('nonaggr_denoised_file', 'bold_cut_file')]),
(bold_mni_trans_wf, add_non_steady_state, [
('outputnode.bold_mni', 'bold_file')]),
(inputnode, add_non_steady_state, [
('skip_vols', 'skip_vols')]),
(add_non_steady_state, outputnode, [('bold_add', 'nonaggr_denoised_file')]),
(ica_aroma, ds_report_ica_aroma, [('out_report', 'in_file')]),
])
return workflow
def init_carpetplot_wf(mem_gb, metadata, name="bold_carpet_wf"):
"""
Resamples the MNI parcellation (ad-hoc parcellation derived from the
Harvard-Oxford template and others).
**Parameters**
mem_gb : float
Size of BOLD file in GB - please note that this size
should be calculated after resamplings that may extend
the FoV
metadata : dict
BIDS metadata for BOLD file
name : str
Name of workflow (default: ``bold_carpet_wf``)
**Inputs**
bold
BOLD image, after the prescribed corrections (STC, HMC and SDC)
when available.
bold_mask
BOLD series mask
confounds_file
TSV of all aggregated confounds
t1_bold_xform
Affine matrix that maps the T1w space into alignment with
the native BOLD space
t1_2_mni_reverse_transform
ANTs-compatible affine-and-warp transform file
**Outputs**
out_carpetplot
Path of the generated SVG file
"""
inputnode = pe.Node(niu.IdentityInterface(
fields=['bold', 'bold_mask', 'confounds_file',
't1_bold_xform', 't1_2_mni_reverse_transform']),
name='inputnode')
outputnode = pe.Node(niu.IdentityInterface(
fields=['out_carpetplot']), name='outputnode')
# List transforms
mrg_xfms = pe.Node(niu.Merge(2), name='mrg_xfms')
# Warp segmentation into EPI space
resample_parc = pe.Node(ApplyTransforms(
float=True,
input_image=str(
get_template('MNI152NLin2009cAsym') /
'tpl-MNI152NLin2009cAsym_space-MNI_res-01_label-carpet_atlas.nii.gz'),
dimension=3, default_value=0, interpolation='MultiLabel'),
name='resample_parc')
# Carpetplot and confounds plot
conf_plot = pe.Node(FMRISummary(
tr=metadata['RepetitionTime'],
confounds_list=[
('global_signal', None, 'GS'),
('csf', None, 'GSCSF'),
('white_matter', None, 'GSWM'),
('std_dvars', None, 'DVARS'),
('framewise_displacement', 'mm', 'FD')]),
name='conf_plot', mem_gb=mem_gb)
ds_report_bold_conf = pe.Node(
DerivativesDataSink(suffix='carpetplot'),
name='ds_report_bold_conf', run_without_submitting=True,
mem_gb=DEFAULT_MEMORY_MIN_GB)
workflow = Workflow(name=name)
workflow.connect([
(inputnode, mrg_xfms, [('t1_bold_xform', 'in1'),
('t1_2_mni_reverse_transform', 'in2')]),
(inputnode, resample_parc, [('bold_mask', 'reference_image')]),
(mrg_xfms, resample_parc, [('out', 'transforms')]),
# Carpetplot
(inputnode, conf_plot, [
('bold', 'in_func'),
('bold_mask', 'in_mask'),
('confounds_file', 'confounds_file')]),
(resample_parc, conf_plot, [('output_image', 'in_segm')]),
(conf_plot, ds_report_bold_conf, [('out_file', 'in_file')]),
(conf_plot, outputnode, [('out_file', 'out_carpetplot')]),
])
return workflow
def init_enhance_and_skullstrip_bold_wf(
name='enhance_and_skullstrip_bold_wf',
pre_mask=False,
omp_nthreads=1):
"""
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 tentative mask by registering (9-parameters) to *fMRIPrep*'s
:abbr:`EPI (echo-planar imaging)` -*boldref* template, which
is in MNI space.
The tentative mask is obtained by resampling the MNI template's
brainmask into *boldref*-space.
2. Binary dilation of the tentative mask with a sphere of 3mm diameter.
3. 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.
4. Calculate a loose mask using FSL's ``bet``, with one mathematical morphology
dilation of one iteration and a sphere of 6mm as structuring element.
5. 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.
6. Calculate a mask using AFNI's ``3dAutomask`` after the contrast
enhancement of 4).
7. Calculate a final mask as the intersection of 4) and 6).
8. Apply final mask on the enhanced reference.
Step 1 can be skipped if the ``pre_mask`` argument is set to ``True`` and
a tentative mask is passed in to the workflow throught the ``pre_mask``
Nipype input.
.. 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``)
pre_mask : bool
Indicates whether the ``pre_mask`` input will be set (and thus, step 1
should be skipped).
omp_nthreads : int
number of threads available to parallel nodes
**Inputs**
in_file
BOLD image (single volume)
pre_mask : bool
A tentative brain mask to initialize the workflow (requires ``pre_mask``
parameter set ``True``).
**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 = Workflow(name=name)
inputnode = pe.Node(niu.IdentityInterface(fields=['in_file', 'pre_mask']),
name='inputnode')
outputnode = pe.Node(niu.IdentityInterface(fields=[
'mask_file', 'skull_stripped_file', 'bias_corrected_file']), name='outputnode')
# Dilate pre_mask
pre_dilate = pe.Node(fsl.DilateImage(
operation='max', kernel_shape='sphere', kernel_size=3.0,
internal_datatype='char'), name='pre_mask_dilate')
# Ensure mask's header matches reference's
check_hdr = pe.Node(MatchHeader(), name='check_hdr',
run_without_submitting=True)
# 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')
if not pre_mask:
bold_template = get_template('fMRIPrep') / 'tpl-fMRIPrep_space-MNI_res-02_boldref.nii.gz'
brain_mask = get_template('MNI152NLin2009cAsym') / \
'tpl-MNI152NLin2009cAsym_space-MNI_res-02_brainmask.nii.gz'
# Initialize transforms with antsAI
init_aff = pe.Node(AI(
fixed_image=str(bold_template),
fixed_image_mask=str(brain_mask),
metric=('Mattes', 32, 'Regular', 0.2),
transform=('Affine', 0.1),
search_factor=(20, 0.12),
principal_axes=False,
convergence=(10, 1e-6, 10),
verbose=True),
name='init_aff',
n_procs=omp_nthreads)
if parseversion(Registration().version) > Version('2.2.0'):
init_aff.inputs.search_grid = (40, (0, 40, 40))
# Set up spatial normalization
norm = pe.Node(Registration(
from_file=pkgr_fn(
'fmriprep.data',
'epi_atlasbased_brainmask.json')),
name='norm',
n_procs=omp_nthreads)
norm.inputs.fixed_image = str(bold_template)
map_brainmask = pe.Node(
ApplyTransforms(interpolation='MultiLabel', float=True, input_image=str(brain_mask)),
name='map_brainmask'
)
workflow.connect([
(inputnode, init_aff, [('in_file', 'moving_image')]),
(inputnode, map_brainmask, [('in_file', 'reference_image')]),
(inputnode, norm, [('in_file', 'moving_image')]),
(init_aff, norm, [('output_transform', 'initial_moving_transform')]),
(norm, map_brainmask, [
('reverse_invert_flags', 'invert_transform_flags'),
('reverse_transforms', 'transforms')]),
(map_brainmask, pre_dilate, [('output_image', 'in_file')]),
])
else:
workflow.connect([
(inputnode, pre_dilate, [('pre_mask', 'in_file')]),
])
workflow.connect([
(inputnode, check_hdr, [('in_file', 'reference')]),
(pre_dilate, check_hdr, [('out_file', 'in_file')]),
(check_hdr, n4_correct, [('out_file', 'mask_image')]),
(inputnode, n4_correct, [('in_file', 'input_image')]),
(inputnode, fixhdr_unifize, [('in_file', 'hdr_file')]),
(inputnode, fixhdr_skullstrip2, [('in_file', 'hdr_file')]),
(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 epi_mni_align(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.
"""
from niworkflows.data import get_mni_icbm152_nlin_asym_09c as get_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"]), name="outputnode")
# Mask PD template image
brainmask = pe.Node(
fsl.ApplyMask(
in_file=op.join(mni_template, "1mm_PD.nii.gz"), mask_file=op.join(mni_template, "1mm_brainmask.nii.gz")
),
name="MNIApplyMask",
)
epimask = pe.Node(fsl.ApplyMask(), name="EPIApplyMask")
# Extract wm mask from segmentation
wm_mask = pe.Node(
niu.Function(input_names=["in_file"], output_names=["out_file"], function=thresh_image), name="WM_mask"
)
wm_mask.inputs.in_file = op.join(mni_template, "1mm_tpm_wm.nii.gz")
flt_bbr_init = pe.Node(fsl.FLIRT(dof=6, out_matrix_file="init.mat"), name="Flirt_BBR_init")
flt_bbr = pe.Node(fsl.FLIRT(dof=12, cost_func="bbr"), name="Flirt_BBR")
flt_bbr.inputs.schedule = op.join(os.getenv("FSLDIR"), "etc/flirtsch/bbr.sch")
# make equivalent warp fields
invt_bbr = pe.Node(fsl.ConvertXFM(invert_xfm=True), name="Flirt_BBR_Inv")
# Warp segmentation into EPI space
segm_xfm = pe.Node(
fsl.ApplyXfm(in_file=op.join(mni_template, "1mm_parc.nii.gz"), interp="nearestneighbour"),
name="ResampleSegmentation",
)
workflow.connect(
[
(inputnode, epimask, [("epi_mean", "in_file"), ("epi_mask", "mask_file")]),
(epimask, flt_bbr_init, [("out_file", "in_file")]),
(epimask, flt_bbr, [("out_file", "in_file")]),
(brainmask, flt_bbr_init, [("out_file", "reference")]),
(brainmask, flt_bbr, [("out_file", "reference")]),
(wm_mask, flt_bbr, [("out_file", "wm_seg")]),
(flt_bbr_init, flt_bbr, [("out_matrix_file", "in_matrix_file")]),
(flt_bbr, invt_bbr, [("out_matrix_file", "in_file")]),
(invt_bbr, segm_xfm, [("out_file", "in_matrix_file")]),
(inputnode, segm_xfm, [("epi_mean", "reference")]),
(segm_xfm, outputnode, [("out_file", "epi_parc")]),
(flt_bbr, outputnode, [("out_file", "epi_mni")]),
]
)
return workflow
def init_enhance_and_skullstrip_bold_wf(
name='enhance_and_skullstrip_bold_wf',
pre_mask=False,
omp_nthreads=1):
"""
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 tentative mask by registering (9-parameters) to *fMRIPrep*'s
:abbr:`EPI (echo-planar imaging)` -*boldref* template, which
is in MNI space.
The tentative mask is obtained by resampling the MNI template's
brainmask into *boldref*-space.
2. Binary dilation of the tentative mask with a sphere of 3mm diameter.
3. 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.
4. Calculate a loose mask using FSL's ``bet``, with one mathematical morphology
dilation of one iteration and a sphere of 6mm as structuring element.
5. 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.
6. Calculate a mask using AFNI's ``3dAutomask`` after the contrast
enhancement of 4).
7. Calculate a final mask as the intersection of 4) and 6).
8. Apply final mask on the enhanced reference.
Step 1 can be skipped if the ``pre_mask`` argument is set to ``True`` and
a tentative mask is passed in to the workflow throught the ``pre_mask``
Nipype input.
.. 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``)
pre_mask : bool
Indicates whether the ``pre_mask`` input will be set (and thus, step 1
should be skipped).
omp_nthreads : int
number of threads available to parallel nodes
**Inputs**
in_file
BOLD image (single volume)
pre_mask : bool
A tentative brain mask to initialize the workflow (requires ``pre_mask``
parameter set ``True``).
**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 = Workflow(name=name)
inputnode = pe.Node(niu.IdentityInterface(fields=['in_file', 'pre_mask']),
name='inputnode')
outputnode = pe.Node(niu.IdentityInterface(fields=[
'mask_file', 'skull_stripped_file', 'bias_corrected_file']), name='outputnode')
# Dilate pre_mask
pre_dilate = pe.Node(fsl.DilateImage(
operation='max', kernel_shape='sphere', kernel_size=3.0,
internal_datatype='char'), name='pre_mask_dilate')
# Ensure mask's header matches reference's
check_hdr = pe.Node(MatchHeader(), name='check_hdr',
run_without_submitting=True)
# 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')
if not pre_mask:
bold_template = get_template('fMRIPrep') / 'tpl-fMRIPrep_space-MNI_res-02_boldref.nii.gz'
brain_mask = get_template('MNI152NLin2009cAsym') / \
'tpl-MNI152NLin2009cAsym_space-MNI_res-02_brainmask.nii.gz'
# Initialize transforms with antsAI
init_aff = pe.Node(AI(
fixed_image=str(bold_template),
fixed_image_mask=str(brain_mask),
metric=('Mattes', 32, 'Regular', 0.2),
transform=('Affine', 0.1),
search_factor=(20, 0.12),
principal_axes=False,
convergence=(10, 1e-6, 10),
verbose=True),
name='init_aff',
n_procs=omp_nthreads)
# Registration().version may be None
if parseversion(Registration().version or '0.0.0') > Version('2.2.0'):
init_aff.inputs.search_grid = (40, (0, 40, 40))
# Set up spatial normalization
norm = pe.Node(Registration(
from_file=pkgr_fn(
'fmriprep.data',
'epi_atlasbased_brainmask.json')),
name='norm',
n_procs=omp_nthreads)
norm.inputs.fixed_image = str(bold_template)
map_brainmask = pe.Node(
ApplyTransforms(interpolation='MultiLabel', float=True, input_image=str(brain_mask)),
name='map_brainmask'
)
workflow.connect([
(inputnode, init_aff, [('in_file', 'moving_image')]),
(inputnode, map_brainmask, [('in_file', 'reference_image')]),
(inputnode, norm, [('in_file', 'moving_image')]),
(init_aff, norm, [('output_transform', 'initial_moving_transform')]),
(norm, map_brainmask, [
('reverse_invert_flags', 'invert_transform_flags'),
('reverse_transforms', 'transforms')]),
(map_brainmask, pre_dilate, [('output_image', 'in_file')]),
])
else:
workflow.connect([
(inputnode, pre_dilate, [('pre_mask', 'in_file')]),
])
workflow.connect([
(inputnode, check_hdr, [('in_file', 'reference')]),
(pre_dilate, check_hdr, [('out_file', 'in_file')]),
(check_hdr, n4_correct, [('out_file', 'mask_image')]),
(inputnode, n4_correct, [('in_file', 'input_image')]),
(inputnode, fixhdr_unifize, [('in_file', 'hdr_file')]),
(inputnode, fixhdr_skullstrip2, [('in_file', 'hdr_file')]),
(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
