C. ROI Derivation Sequence

If an ROI is created by re-sampling an existing ROI that is either (a) present in a different Frame of Reference (FoR) and has been resampled to align with the image series referenced by the current structure set, or (b) present in the same FoR, but its contours are referenced to a different image series, it is useful to be able to identify that the ROI is resampled. The Derivation Code Sequence (0008,9215) shall be used with code (113085, DCM, "Spatial resampling") to indicate the resampled ROI.