I have segmented T1-W MR images from the ADNI database using Freesurfer. From aseg.nii, I have estimated the fornix structure (label number 250). I tried many times to get the characteristics of these structures but couldn't. It would be helpful for me; kindly let me know. 

File name "fornix.nii" at label 250. Its statistical parameters, such as fractal dimension, volume, mean, etc