def ss_item
      item = DICOM::Item.new
      item.add(DICOM::Element.new(ROI_NUMBER, @number.to_s))
      item.add(DICOM::Element.new(REF_FRAME_OF_REF, @frame.uid))
      item.add(DICOM::Element.new(ROI_NAME, @name))
      item.add(DICOM::Element.new(ROI_ALGORITHM, @algorithm))
      return item
    end
def ss_item
      item = DICOM::Item.new
      item.add(DICOM::Element.new(ROI_NUMBER, @number.to_s))
      item.add(DICOM::Element.new(REF_FRAME_OF_REF, @frame.uid))
      item.add(DICOM::Element.new(ROI_NAME, @name))
      item.add(DICOM::Element.new(ROI_ALGORITHM, @algorithm))
      return item
    end
Creates a Structure Set ROI Sequence Item from the attributes of the Structure instance.

 @return [DICOM::Item] a structure set ROI sequence item