Hi Koen and FreeSurfers:<br><br>I have a 3T dataset that has undergone processing using 5.1. I have also run the Hippo sub fields command. Here are my results:<br><br>[root@NeuroImage-Gamma mri]# kvlQuantifyPosteriorProbabilityImages $FREESURFER_HOME/data/GEMS/compressionLookupTable.txt posterior_right_* posterior_Right-Hippocampus.mgz<br>
<br>volumeInVoxels: <br>    right_CA1: 2473.34<br>    right_CA2-3: 7530.08<br>    right_CA4-DG: 4160.99<br>    right_fimbria: 520.14<br>    right_hippocampal_fissure: 376.772<br>    right_presubiculum: 2780.65<br>    right_subiculum: 4230.04<br>
    Right-Hippocampus: 2277.69<br><br>My question is :  Since these are &quot;subfields&quot; of the Hippocampus, should not the sum of all subregions  be equal the volume of the Right Hippocampus?<br><br>Thanks so much!<br>
<br>Alan Francis<br><br>Beth Israel Deaconess Medical Center, BOSTON<br><br>