MRICloudCalculateCBF

Purpose. Compute absolute (aCBF) and relative (rCBF) maps in native perfusion space using MRICloud equations.

Workflow

  • Uses r{asl}_diff.nii (difference), M0map.nii, and the two brain masks.

  • Handles PCASL and PASL timing (PLD/TI, slice timing, labeling duration).

  • Applies background suppression scaling (alpha).

Inputs

  • r{asl}_diff.nii from MRICloudCalculateDiffmap

  • M0map.nii, brnmsk_dspl.nii, brnmsk_clcu.nii from MRICloudCalculateM0

  • Timing and acquisition fields in data_descrip: - ArterialSpinLabelingType (PCASL/PASL), PLDList, SliceDuration,

    MRAcquisitionType (2D/3D), LabelingDuration (PCASL), BolusCutOffDelayTime (PASL), background suppression metadata.

Outputs

  • {asl}_aCBF_native.nii — absolute CBF (clipped to [0, 200])

  • {asl}_rCBF_native.nii — relative CBF (normalized by global mean over brnmsk_clcu)

Configuration

Key

Type / Default

Meaning

t1_blood

int / 1650

Blood T1 (ms)

part_coef

float / 0.9

Partition coefficient (λ)

bgs_eff

float / 0.93

Background suppression efficiency

YAML example

modules:
  - name: MRICloudCalculateCBF
    params:
      t1_blood: 1650
      part_coef: 0.9
      bgs_eff: 0.93