• 1 - A condition where surgery has been performed (Surgical code)
• 2 - A condition where no surgery has been performed (non-surgical code)
  • 4 - Neurological (including eyes)
    • 2 - Brain, CSF, meninges or skull vault
      • 41 - Vascular
        • 1 - Berry or other intracranial aneurysm
        • 2 - Intracranial arterio-venous malformation
        • 3 - Thrombo-occlusive disease of brain
        • 4 - Arterial air embolus
        • 5 - Vasculitis of cerebral circulation
        • 6 - Embolic brain lesions causing respiratory failure
        • 7 - Venous sinus thrombosis