Cortical mask for fmriprep MNI output space

Hi all,

I’ve got pre-processed data from fmriprep in the MNI152NLin2009cAsym output space.

Where would I find a cortical mask for this data in volume space (i.e. cortical mask to use with the *_space-MNI152NLin2009cAsym_desc-preproc_bold.nii.gz outputs)?

I guess one option is to use the desc-aparcaseg_dseg segmentation and pull out all of the ‘ctx’ voxels, but I figured something like this would already be available?

I am aware of the fsaverage surface output space option but I would like to stick with volume space.

Thanks,
Dror