Operation on liver (procedure)

• Hepatic operation
• Liver operation
• Operation on liver

• Procedure on liver (procedure) and Role group (attribute) some (
      Method (attribute) some Surgical action (qualifier value) and
      Procedure site (attribute) some Liver structure (body structure))

• Operative procedure on digestive organ (procedure)
• Operation on abdominal region (procedure)
• Procedure on liver (procedure)