The oro.dicom package allows input and output of data that adapts to the Digital Imaging and Communications in Medicine (DICOM) standard. The DICOM list organization is used to produce a multi-dimensional array representing a single acquisition of medical imaging data. The oro.nifti package facilitates the input/output and visualization of medical imaging data. It uses the ANALYZE or NIFTI format. tractor.base (part of the tractor project)package is made up of functions which are used for reading,writing and visualization of MRI images. The images might have been stored up in the DICOM or ANALYZE format.It also provides functions for image manipulation and for applying arbitrary functions to image data.