> For the complete documentation index, see [llms.txt](https://netstim.gitbook.io/leaddbs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://netstim.gitbook.io/leaddbs/lead-dbs/step4-optional-surface-reconstruction.md).

# 4. (optional) Surface Reconstruction

This is an optional step to perform surface reconstruction. One approach uses the Computational Anatomy Box (CAT12), which is an extension of SPM12. CAT12 uses a completely different segmentation approach. Read more on [their website](https://www.neuro.uni-jena.de/cat/). Another approach uses Freesurfer. See [their website](https://surfer.nmr.mgh.harvard.edu) for more details.