incision vs perforation

incision

noun
  • The act of cutting into a substance. 

  • A cut-back 

  • A cut, especially one made by a scalpel or similar medical tool in the context of surgical operation; the scar resulting from such a cut. 

perforation

noun
  • The act of perforating or the state of being perforated. 

  • That portion of a surface that remains after an open disk is removed from it. 

  • A series of holes punched through something in order to assist in separating parts. 

  • An abnormal opening in an organ, such as a rupture. 

  • Any opening in a solid object. 

How often have the words incision and perforation occurred in a corpus of books? (source: Google Ngram Viewer )