Third Nerve Palsy

Question 1

what is the clinical features of 3rd nerve palsy?

Answer 1

• eye is deviated ‘down and out’
• ptosis
• pupil may be dilated (somtimes called a ‘surgical’ third nerve palsy)

Question 2

what are the causes of 3rd nerve palsy?

Answer 2

• diabetes
• vasculitis
• uncal herniation
• posterior communicating artery aneurysm
• cavernous sinus thrombosis
• weber’s syndrome
• amyloid
• multiple sclerosis

Question 3

how does uncal herniaton present?

Answer 3

• false localising sign (6th nerve palsies or other neurological presentations)
• 3rd nerve palsy
• loss of consciousness
• hypertension
• bradycardia
• cheyne-stokes respiration

Question 4

what is uncal herniation?

Answer 4

herniation through tentorium due to raised ICP

Question 5

how does posterior communicating artery aneurysm present?

Answer 5

• 3rd nerve palsy
• pupil dilated
• often associated with pain

Question 6

painful third nerve palsy

Answer 6

exclude posterior communicating artery aneurysm