Recent developments Neuroimaging studies have revealed specific activation patterns in various primary headaches. In the trigeminal autonomic cephalgias, neuroimaging findings support the hypothesis that activation of posterior hypothalamic neurons have a pivotal role in the pathophysiology and prompted the idea that hypothalamic stimulation might inhibit this activation to improve or eliminate the pain in intractable chronic cluster headache and other trigeminal autonomic cephalgias. Over the past 6 years, hypothalamic implants have been used in various centres in patients with intractable chronic cluster headache. The results are encouraging: most patients achieved stable and notable pain reduction and many became pain free. All deep-brain-electrode implantation procedures carry a small risk of mortality due to intracerebral. haemorrhage. Before implantation, all patients must undergo complete preoperative neuroimaging to exclude disorders associated with increased haemorrhagic risk. No substantial changes in hypothalamus-controlled functions have been reported during hypothalamic stimulation. Hypothalamic stimulation may also be beneficial in patients with SUNCT (short-lasting, unilateral, neuralgiform headache attacks with conjunctival injection and tearing)-a disorder with close clinical and neuroimaging similarities to the cluster headache.