xcp_d.utils.utils.estimate_brain_radius

xcp_d.utils.utils.estimate_brain_radius(mask_file, head_radius='auto')[source]

Estimate brain radius from binary brain mask file.

Parameters:

mask_file (str) – Binary brain mask file, in nifti format.
head_radius (float or “auto”) – Radius of the head, in millimeters, for framewise displacement calculation.

xcp_d’s default head radius is 50. The recommended value for infants is 35. A value of ‘auto’ is also supported, in which case the brain radius is estimated from the preprocessed brain mask.

Returns:

brain_radius – Estimated brain radius, in millimeters.

Return type:

float

Notes

This function estimates the brain radius based on the brain volume, assuming that the brain is a sphere. This was Paul Taylor’s idea, shared in this NeuroStars post: https://neurostars.org/t/estimating-head-brain-radius-automatically/24290/2.