Crop dicom around a point, automate the process

I use slicer to display some dicom files (3D scans) and save them as a nrrd file.
The nrrd file is too big for me, I need to crop this file around the center of the cube.
How can I do this?

I need to do for at least 300 Dicom file, is there a way to automate the process to deal with this amount of file? by writing a python script for instance?
Thanks for any pointers or advice to do this.