Clinical features

There are three main presentations of Berry aneurysms:

• 90% present with a subarachnoid haemorrhage
  
  
• 7% present with symptoms of a space-occupying lesion:
  
  
• internal carotid artery or anterior communicating artery aneurysms may compress:
  • pituitary stalk or hypothalamus causing hypopituitarism
  • the optic nerve or chiasm producing visual field defects
    
    
• basilar artery aneurysm may compress the midbrain or pons to produce limb weakness or impaired eye movements
  
  
• posterior communicating artery aneurysm may cause a III nerve palsy
  
  
• intracavernous aneurysms may compress the III, IV, VI, trigeminal division of V and trigeminal ganglion to produce ophthalmoplegia and facial pain
  
  
• 3% occur as incidental findings at autopsy