A 30 year old man with a history of migraine presented at the neurology outpatient clinic with hypesthesia of the left side of his body during a migraine attack, which was unusual for him. His family history was positive for Rendu-Osler-Weber syndrome. MRI and magnetic resonance angiography (MRA) of the brain showed multiple small infarcts, without vascular malformations. CT angiography revealed an arteriovenous fistula in the lung. Rendu-Osler-Weber syndrome (or hereditary haemorrhagic telangiectasia, HHT) is an autosomal dominant condition affecting the blood vessels. It is estimated that about 60-80% of the patients with a pulmonary arteriovenous malformation (AVM) have HHT. Neurological complications include cerebral infarction and brain abscess. Also, there is a higher prevalence of migraine in patients with HHT, although the role that HHT plays in the pathogenesis of migraine is unclear. The treatment of choice of pulmonary AVM is endovascular treatment, with a success rate of 75% in the long term.