• 1 - A condition where surgery has been performed (Surgical code)
  • 4 - Neurological (including eyes)
    • 1 - Head, neck (extracranial) or eyes
      • 57 - Non-traumatic aneurysm or dissection
        • 1 - Non-traumatic carotid or vertebral artery aneurysm or dissection
• 2 - A condition where no surgery has been performed (non-surgical code)