Hypothalamic stimulation in chronic cluster headache: a pilot study of efficacy and mode of action

Abstract

We enrolled six patients suffering from refractory chronic cluster headache in a pilot trial of neurostimulation of the ipsilateral ventroposterior hypothalamus using the stereotactic coordinates published previously. After the varying durations needed to determine optimal stimulation parameters and a mean follow-up of 14.5 months, the clinical outcome is excellent in three patients (two are pain-free; one has fewer than three attacks per month), but unsatisfactory in one patient, who only has had transient remissions. Mean voltage is 3.28 V, diplopia being the major factor limiting its increase. When the stimulator was switched off in one pain-free patient, attacks resumed after 3 months until it was turned on again. In one patient the implantation procedure had to be interrupted because of a panic attack with autonomic disturbances. Another patient died from an intracerebral haemorrhage that developed along the lead tract several hours after surgery; there were no other vascular changes on post-mortem examination. After 1 month, the hypothalamic stimulation induced resistance against the attack-triggering agent nitroglycerin and tended to increase pain thresholds at extracephalic, but not at cephalic, sites. It had no detectable effect on neurohypophyseal hormones or melatonin excretion. We conclude that hypothalamic stimulation has remarkable efficacy in most, but not all, patients with treatment-resistant chronic cluster headache. Its efficacy is not due to a simple analgesic effect or to hormonal changes. Intracerebral haemorrhage cannot be neglected in the risk evaluation of the procedure. Whether it might be more prevalent than in deep-brain stimulation for movement disorders remains to be determined.

Deep Brain Stimulation in Trigeminal Autonomic Cephalalgias

“…41 In a study from a Belgian center, two of the four patients with hypothalamic implants were pain free and one had improved substantially. 37 In a study from Oxford, UK, all three patients with hypothalamic implants were reported as pain free and with no adverse effects after a follow-up of 6 months to 2 years. 39,47 Other outcomes from studies presented only in abstract form are included in Table 1, [42][43][44]48 along with data from one unpublished study.…”

“…38 In one study, one of the six patients implanted died soon after the operation, because of implantation-induced intracerebral hemorrhage; in another patient, the implantation was stopped because of panic attack. 37 It is possible that this patient had anxiety disorder; alternatively, the electrode may have missed the target. Panic attacks have been reported during periaqueductal stimulation, 3 but not during hypothalamic implantation or stimulation.…”

“…34,37,40,41,46,57,58 In all but one study, 47 the microrecordings were obtained from patients not experiencing an attack (i.e., under basal conditions). Franzini et al 34 used a Medtronic (Minneapolis, MN) lead point system to investigate the target area.…”

“…They presented a figure illustrating electrical activity in a single unit, but provided no quantitative data. Schoenen et al 37 obtained data from the area defined by the stereotactic coordinates of Leone et al 16 in four chronic cluster headache patients. They used a Medtronic 9013-SD-08411 microelectrode and Medtronic lead point system, starting 10 mm above the target and continuing at 1-mm intervals down to the target.…”

“…They used a Medtronic 9013-SD-08411 microelectrode and Medtronic lead point system, starting 10 mm above the target and continuing at 1-mm intervals down to the target. 37 No additional procedural details were given, and no quantitative data. No specific neuronal activity-similar to that found in DBS of the subthalamic nucleus and globus palliduswas found, but in two patients bursts of action potentials synchronous with heart beats were recorded.…”