Hello, 

I’ve run into an issue during preprocessing: while the pipeline (using the direct normalization) worked well for most participants, it seems that for 3 subjects, the skull-stripping step didn’t complete properly, i.e. the skull remains clearly visible in their anatomical images ( unlike the others, where skull-stripping was successful.)

Any idea why this might happen selectively for just a few individuals? Are there known issues that could cause the skull-stripping to fail (e.g., poor image quality, motion artifacts, unusual anatomy)?

Also, do you have any suggestions for how to fix this? 

Thanks

Belina