[Freesurfer] FOV Size Discrepancy

Hello!

I was hoping someone can provide me with some clarification on an issue I have been having with the FOV size.

I have a database of scans which I am running through recon-all cross-sectionally. The majority of the scans have an FOV of 256x256x208; however, when I run them through recon-all I get an error message indicating that the FOV is larger than 256 (282x282x228). When I use the -cw256 flag, recon-all runs through successfully. I do not understand why recon-all thinks the FOV is larger then it is. I double checked that the FOV size is 256 using the mri_info command line and the database information. Does anyone know why recon-all is listing a larger FOV size?

Thank you in advance for your help.

Tamara