Recon-all fails with signal 11 during mris_fix_topology on FLAWS-hco data (giant defect, 240k vertices)

Hi everyone,

I am trying to run recon-all on FLAWS-hco images (derived from a 3T FLAWS sequence, 1mm isotropic, with T1-like contrast: WM bright, GM gray, CSF dark). The pipeline successfully completes all steps up to topology fixing, but then crashes with signal 11 during left hemisphere mris_fix_topology.

FreeSurfer version: freesurfer-linux-ubuntu22_x86_64-7.4.1-20230614-7eb8460
OS: Ubuntu 24.04, kernel 6.17.0-14-generic
Command: recon-all -s subject01 -i FLAWS_HCO-DEN.nii.gz -all

**Error log:**CORRECTING DEFECT 0 (vertices=240980, convex hull=31271, v0=24)
Command terminated by signal 11

The defect size is enormous (240,980 vertices). I have tried:

  • Increasing swap space to ~15.6 GB total
  • ulimit -v unlimited
  • export OMP_NUM_THREADS=2
  • Memory was not exhausted during the run

Visual inspection confirms that wm.mgz contains mislabeled cerebellum and dura mater, which likely causes this giant defect.

Questions:

  1. Is manual editing of wm.mgz the only solution for such a large defect? If so, what is the recommended workflow in FreeView?
  2. Are there any flags or environment variables to make mris_fix_topology more tolerant to large defects?
  3. Has anyone successfully processed FLAWS-hco images with FreeSurfer?

Full log and screenshots attached. Any help would be greatly appreciated!

Thanks!

in my experience most of such topolographical defects are due to bad skullstrips. You might want to use mri_synthstrip to skullstrip your input image before running recon-all on it

or you can try using the latest freesurfer (v.8.2.0), which uses mri_synthstrip in its workflow