Transform a volume from MNI space to SUIT cerebellar space

Resamples a volumetric parcellation from MNI152 space into the SUIT cerebellar template space using a nonlinear deformation field. This is required when working with cerebellar atlases that are distributed in MNI space (e.g., the Buckner cerebellar network parcellations shipped with FreeSurfer).

The deformation field must be a 5D NIfTI file where each SUIT-space voxel stores the corresponding MNI coordinate to sample from. These are available from the Diedrichsen Lab cerebellar atlases repository as tpl-SUIT_from-MNI152NLin*_mode-image_xfm.nii.

Usage

transform_mni_to_suit(
  input_volume,
  deformation_field,
  output_file = NULL,
  interpolation = c("nearest", "linear")
)

Arguments

input_volume

Path to the MNI-space volume (NIfTI).

deformation_field

Path to the SUIT deformation field NIfTI. A 5D volume (x, y, z, 1, 3) mapping SUIT voxels to MNI coordinates.

output_file

Path for the output SUIT-space volume. If NULL, writes to a temporary file.

interpolation

Interpolation method: "nearest" (default, for parcellations/labels) or "linear" (for continuous maps). Note that "linear" uses a pure-R trilinear loop and can be slow for large volumes.

Value

Path to the output SUIT-space NIfTI file (invisibly).

Examples

if (FALSE) { # \dontrun{
suit_vol <- transform_mni_to_suit(
  input_volume = "Buckner2011_7Networks.nii.gz",
  deformation_field = "tpl-SUIT_from-MNI152NLin6AsymC_mode-image_xfm.nii"
)
atlas <- create_cerebellar_from_volume(input_volume = suit_vol)
} # }