30th December 2024

Malignant raised intracranial pressure (ICP)

Overview of malignant raised ICP

Both primary and metastatic brain lesions can cause raised ICP due to mass effect or hydrocephalus.

Patients with cancer are also at increased risk of developing raised ICP due to non-neoplastic causes including intracranial haemorrhage (with thrombocytopenia or coagulopathy) and CNS infections (if immunocompromised).

Any of these causes of raised ICP can result in herniation and death and must be recognised and treated early.

Presentation of malignant raised ICP

Symptoms of malignant raised ICP

Patients usually complain of a headache that is characteristically worse in the mornings (or after lying flat) and relieved on standing up. It may be worsened by valsalva manoeuvres such as coughing or sneezing.

It is also common for patients to describe progressive nausea and vomiting.

There may be cognitive change or impairment, drowsiness, and in severe cases, seizures and reduced GCS.

Examination in malignant raised ICP

Fundoscopy may show papilloedema.

Neurological examination may reveal disturbed gait, weakness or sensory loss depending on tumour location.

There may be other ‘false localising’ signs due to raised ICP, including cranial nerve palsies, most commonly CN VI palsy (paralysis of the medial rectus and failure of the eye to abduct). There may also be palsies of CN V (facial numbness) and CN VII (facial weakness).

If there is transtentorial herniation, there may be a surgical CN III palsy (ipsilateral mydriasis), which may be followed by complete CN III palsy (ptosis and down-and-out orientation of the eye) as the herniation progresses. Herniation will eventually result in midbrain compression – causing coma, altered respiratory and cardiovascular control, bradycardia and hypertension.

Investigations in malignant raised ICP

Symptoms of malignant raised ICP

MRI with contrast is the most sensitive investigation for intracranial malignancy as, compared to CT, it demonstrates better anatomical detail, may better delineate meningeal spread and is more likely to reveal multiple lesions.

However, if there will be a delay to MRI imaging, or MRI is contraindicated, initial investigation with a contrast CT head is reasonable and in the majority of cases will demonstrate an enhancing lesion.

Management of malignant raised ICP

The aims of initial management are to reduce oedema with high-dose corticosteroids, relieve symptoms and prevent or treat seizures. Urgent neurosurgical or oncological or neurosurgical advice is required to advise on definitive management.

References

• Cassidy J, Bissett D, Spence RAJ, Payne M, Morris-Stiff GJ. Oxford Handbook of Oncology. 4th ed. Oxford: Oxford University Press; 2015
• Larner AJ. False localising signs. Journal of Neurology, Neurosurgery & Psychiatry. 2003 Apr 1;74(4):415–8
• National Institute for Healthcare and Excellence. Palliative care – nausea and vomiting. NICE [Internet]. 2021 [cited 2022 Apr 17]. Available from: https://cks.nice.org.uk/topics/palliative-care-nausea-vomiting/