24B. Symptoms of raised intracranial pressure

Symptoms of increased ICP

  • Reduced level of consciousness
  • Headache
  • Vomiting
  • Papilloedema -> blurred vision
  • Abducent palsy -> diplopia
  • Cushing triad/reflex
    • Hypertension
    • Bradycardia
    • Irregular respiration

Types of intracranial herniation

Generally, herniation can cause decrease level of consciousness, anisocoria, hemiparesis or tetraparesis.

Uncal transtentorial herniation occurs if the uncus herniates at tentorial incisure. This is often due to a unilateral mass effect. The clinical features are:

  • Impaired consciousness
  • Ipsilateral CN III palsy – Fixed, dilated pupil (Hutchinson’s pupil)
  • Contralateral motor deficit
  • Ipsilateral motor deficit (Kernohan’s sign)
    • Due to compression of the contralateral cerebral peduncle
    • (One of the rare cases where a cortical lesion causes ipsilateral motor signs)

Foramen magnum (tonsillar) herniation occurs if the cerebral tonsils herniate through foramen magnum. This causes compression of brainstem, which impairs consciousness, circulation, and respiration, and can be deadly.


Previous page:
24A. Paraneoplastic nervous system diseases

Next page:
25A. Focal dystonias

Leave a Reply

Your email address will not be published.