Summary

• Congenital vascular lesions that enlarge with age.
• Most commonly present with haemorrhage.
• Diagnosis is made by brain CT or MRI and angiography.
• Risk of arteriovenous malformation (AVM) rupture is reduced only by complete exclusion of the AVM from the intracranial circulation. Definitive treatment options include surgical excision and stereotactic radiosurgery. Endovascular embolisation is generally used as an adjunct.
• Management decisions are made in the light of the lifetime risk of haemorrhage versus the risk of treatment.