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Structural Image Evaluation using Normalisation of Atrophy (SIENA)

Library: FSL | Docker Image: brainlife/fsl

Function

Multi-step pipeline that estimates percentage brain volume change between two timepoints. Internally chains BET brain extraction, registration, FAST segmentation, and edge-point displacement analysis.

Modality: Two T1-weighted 3D NIfTI volumes from different timepoints.

Typical Use: Measuring brain volume change over time (e.g., atrophy in neurodegeneration).

Key Parameters

-o (output directory), -BET (BET options), -2 (2-class segmentation), -S (SIENA step options)

Key Points

Requires two scans of same subject at different timepoints. Reports percentage brain volume change (PBVC). Accurate to ~0.2% volume change.

Inputs

Name Type Required Label Flag
input1 File Yes Input T1 image (timepoint 1)
input2 File Yes Input T1 image (timepoint 2)
output_dir string No Output directory name -o
bet_options string No BET options (e.g., "-f 0.3") -B
two_class boolean No Two-class segmentation (no grey/white separation) -2
t2_weighted boolean No Inputs are T2-weighted -t2
std_masking boolean No Apply standard-space masking for difficult cases -m
siena_diff_options string No Options to pass to siena_diff (e.g., "-s -i 20") -S
ventricle_analysis boolean No Activate ventricular analysis (VIENA) -V
ventricle_mask File No Custom ventricle mask -v
top_threshold double No Ignore from this height (mm) upwards in MNI space -t
bottom_threshold double No Ignore from this height (mm) downwards in MNI space -b
debug boolean No Debug mode (keep intermediate files) -d

Accepted Input Extensions

  • input1: .nii, .nii.gz
  • input2: .nii, .nii.gz
  • ventricle_mask: .nii, .nii.gz

Outputs

Name Type Glob Pattern
output_directory Directory $(inputs.output_dir || '*_to_*_siena')
report File $(inputs.output_dir || '*_to_*_siena')/report.siena
pbvc File $(inputs.output_dir || '*_to_*_siena')/report.sienax
edge_points File[] $(inputs.output_dir || '*_to_*_siena')/*_edge*.nii.gz, $(inputs.output_dir || '*_to_*_siena')/*_edge*.nii
flow_images File[] $(inputs.output_dir || '*_to_*_siena')/*_flow*.nii.gz, $(inputs.output_dir || '*_to_*_siena')/*_flow*.nii
log File siena.log

Output Extensions

  • report: .siena
  • pbvc: .sienax
  • edge_points: .nii, .nii.gz
  • flow_images: .nii, .nii.gz

Docker Tags

Available versions: latest, 6.0.4-patched2, 6.0.4-patched, 6.0.4, 6.0.4-xenial, 5.0.11, 6.0.0, 6.0.1, 5.0.9

Categories

  • Structural MRI > FSL > Pipelines
  • Pipelines > FSL > Structural

Documentation

Official Documentation