Neurostimulation in primary headache syndromes

Invasive and Non-invasive Electrical Pericranial Nerve Stimulation for the Treatment of Chronic Primary Headaches

Chronic primary headaches are widespread disorders which cause significant quality of life and socioprofessional impairment. Available pharmacological treatments have often a limited efficacy and/or can generate unbearable side effects. Electrical nerve stimulation is a well-known non-destructive method of pain modulation which has been recently applied to headache management. In this review, we summarise recent advances in invasive and non-invasive neurostimulation techniques targeting pericranial structures for the treatment of chronic primary headaches, chiefly migraine and cluster headache: occipital nerve, supraorbital nerve, vagus nerve, and sphenopalatine ganglion stimulations. Invasive neurostimulation therapies have offered a new hope to drug-refractory headache sufferers but are not riskless and should be proposed only to chronic patients who failed to respond to most existing preventives. Non-invasive neurostimulation devices are user-friendly, safe and well tolerated and are thus taking an increasing place in the multidisciplinary therapeutical armamentarium of primary headaches.

Hemicrania Continua: Beneficial Effect of Non-Invasive Vagus Nerve Stimulation in a Patient With a Contraindication for Indomethacin

Hemicrania continua (HC) is a primary chronic headache disorder, characterized by a continuous and strictly unilateral headache, with possible cranial autonomic symptoms during episodes of pain exacerbation. The unilateral headache generally responds well to indomethacin; however, continuous indomethacin intake is often not tolerated due to severe adverse effects, like hypertension, gastrointestinal discomfort (especially if combined with aspirin), slightly increased risk of vascular events, and bronchial spasms. Therefore, alternative treatment options are desperately needed. Non-invasive vagus nerve stimulation (nVNS) has been shown to be effective in patients with cluster headache, another trigeminal autonomic cephalalgia (TAC), with cranial parasympathetic autonomic activation during the attacks.

Refractory chronic migraine: a consensus statement on clinical definition from the European Headache Federation

The debate on the clinical definition of refractory Chronic Migraine (rCM) is still far to be concluded. The importance to create a clinical framing of these rCM patients resides in the complete disability they show, in the high risk of serious adverse events from acute and preventative drugs and in the uncontrolled application of therapeutic techniques not yet validated.

The European Headache Federation Expert Group on rCM presents hereby the updated definition criteria for this harmful subset of headache disorders. This attempt wants to be the first impulse towards the correct identification of these patients, the correct application of innovative therapeutic techniques and lastly aim to be acknowledged as clinical entity in the next definitive version of the International Classification of Headache Disorders 3 (ICHD-3 beta).

Supraorbital and supratrochlear stimulation for trigeminal autonomic cephalalgias

Trigeminal autonomic cephalalgias (TAC) is a rare primary headache disorder with challenging and limited treatment options for those unfortunate patients with severe and refractory pain. This article will review the conventional pharmacologic treatments as well as the new neuromodulation techniques designed to offer alternative and less invasive treatments. These techniques have evolved from the treatment of migraine headache, a much more common headache syndrome, and expanded towards application in patients with TAC. Specifically, the article will discuss the targeting of the supratrochlear and supraorbital nerves, both terminal branches of the trigeminal nerve.

Role of trigeminal microvascular decompression in the treatment of SUNCT and SUNA

Short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT) and short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA) are primary headache disorders. Evidence suggests that SUNCT/SUNA have similar pathophysiology to the trigeminal autonomic cephalalgias and involves the trigeminal autonomic reflex. This review provides an overview of microvascular decompression of the trigeminal nerve and other surgical therapeutic options for SUNCT/SUNA. We have undertaken a mini-meta-analysis of available case reports and case series with the aim of providing recommendations for the use of such therapies in SUNCT/SUNA. There is some evidence supporting microvascular decompression of the trigeminal nerve in selected patients who have medically refractory SUNCT/SUNA and a demonstrable ipsilateral aberrant vessel on magnetic resonance imaging (MRI). We also consider what further investigations could be undertaken to assess the role of surgical interventions in the treatment of these often debilitating conditions.

Neuromodulation for cephalgias

Headaches (cephalgias) are a common reason for patients to seek medical care. There are groups of patients with recurrent headache and craniofacial pain presenting with malignant course of their disease that becomes refractory to pharmacotherapy and other medical management options. Neuromodulation can be a viable treatment modality for at least some of these patients. We review the available evidence related to the use of neuromodulation modalities for the treatment of medically refractory craniofacial pain of different nosology based on the International Classification of Headache Disorders, 2(nd) edition (ICHD-II) classification. This article also reviews the scientific rationale of neuromodulation application in management of cephalgias.

Occipital nerve stimulation for medically refractory hypnic headache

OBJECTIVE

Hypnic headache is a rare, primary headache disorder that exclusively occurs regularly during sleep. We present a case of hypnic headache successfully managed with occipital nerve stimulation.

MATERIALS AND METHODS

A 64-year-old female presented with a four-year history of a right occipital headache that regularly awakened her from sleep. The headache, which was dull and throbbing, would awaken her regularly at 4:00 am, five hours after bedtime at 11:00 pm. No photophobia, nausea or vomiting, lacrimation, or other autonomic symptoms were present. The headache was refractory to various medical treatments, including indomethacin, flunarizine, propranolol. She underwent a trial of occipital nerve stimulation with a lead electrode using a medial approach.

RESULTS

During the ten-day trial stimulation, she reported almost complete relief from hypnic headache. Chronic occipital nerve stimulation replicated the trial results. The attacks of hypnic headache recurred in one year with loss of stimulation-induced paresthesia; a subsequent x-ray showed electrode migration. After revision of the electrode to the original location, the effectiveness of the occipital nerve stimulation against hypnic headache was achieved again, and this effect has been consistent through 36 months of follow-up.

CONCLUSION

Occipital nerve stimulation was effective in a patient with chronic, refractory hypnic headache.

Cluster headache: clinical features and therapeutic options

BACKGROUND

Cluster headache is the most common type of trigemino-autonomic headache, affecting ca. 120 000 persons in Germany alone. The attacks of pain are in the periorbital area on one side, last 90 minutes on average, and are accompanied by trigemino-autonomic manifestations and restlessness. Most patients have episodic cluster headache; about 15% have chronic cluster headache, with greater impairment of their quality of life. The attacks often possess a circadian and seasonal rhythm.

METHOD

Selective literature review

RESULTS

Oxygen inhalation and triptans are effective acute treatment for cluster attacks. First-line drugs for attack prophylaxis include verapamil and cortisone; alternatively, lithium and topiramate can be given. Short-term relief can be obtained by the subcutaneous infiltration of local anesthetics and steroids along the course of the greater occipital nerve, although most of the evidence in favor of this is not derived from randomized clinical trials. Patients whose pain is inadequately relieved by drug treatment can be offered newer, invasive treatments, such as deep brain stimulation in the hypothalamus (DBS) and bilateral occipital nerve stimulation (ONS).

CONCLUSION

Pharmacotherapy for the treatment of acute attacks and for attack prophylaxis is effective in most patients. For the minority who do not gain adequate relief, newer invasive techniques are available in some referral centers. Definitive conclusions as to their value cannot yet be drawn from the available data.

14th International Headache Congress: clinical highlights

The 14th International Headache Congress was held in Philadelphia in September 2009. During the Congress, many important basic, translational, and patient-oriented research studies were presented. In this and an accompanying manuscript, the work that has been deemed to be among the most innovative and significant is summarized. This manuscript discusses the best clinical research, while the accompanying manuscript summarizes the top basic science research. Here, we provide background and summarize Congress presentations on novel agents for migraine treatment, botulinum toxin therapy for chronic migraine, new methods for administration of headache medications, and nerve stimulation for the treatment of medically refractory headaches.

Occipital nerve stimulation for headache disorders

Occipital nerve stimulation (ONS) was originally described in the treatment of occipital neuralgia. However, the spectrum of possible indications has expanded in recent years to include primary headache disorders, such as migraine and cluster headaches. Retrospective and some prospective studies have yielded encouraging results, and evidence from controlled clinical trials is emerging, offering hope for refractory headache patients. In this article we discuss the scientific rationale to use ONS to treat headache disorders, with emphasis on the trigeminocervical complex. ONS is far from a standardized technique at the moment and the recent literature on the topic is reviewed, both with respect to the procedure and its possible complications. An important way to move forward in the scientific evaluation of ONS to treat refractory headache is the clinical phenotyping of patients to identify patients groups with the highest likelihood to respond to this modality of treatment. This requires multidisciplinary assessment of patients. The development of ONS as a new treatment for refractory headache offers an exciting prospect to treat our most disabled headache patients. Data from ongoing controlled trials will undoubtedly shed new light on some of the unresolved questions.

Combined occipital and supraorbital neurostimulation for the treatment of chronic migraine headaches: Initial experience

A novel approach to the treatment of chronic migraine headaches based on neurostimulation of both occipital and supraorbital nerves was developed and reduced to clinical practice in a series of patients with headaches unresponsive to currently available therapies. Following positive trials, seven patients with chronic migraine and refractory chronic migraine headaches had permanent combined occipital nerve–supraorbital nerve neurostimulation systems implanted. The relative responses to two stimulation programs were evaluated: one that stimulated only the occipital leads and one that stimulated both the occipital and supraorbital leads together. With follow-up ranging from 1 to 35 months all patients reported a full therapeutic response but only to combined supraorbital–occipital neurostimulation. Occipital nerve stimulation alone provided a markedly inferior and inadequate response. Combined occipital nerve–supraorbital nerve neurostimulation systems may provide effective treatment for patients with chronic migraine and refractory chronic migraine headaches. For patients with chronic migraine headaches the response to combined systems appears to be substantially better than occipital nerve stimulation alone.

Long term clinical outcome of peripheral nerve stimulation in patients with chronic peripheral neuropathic pain

BACKGROUND

Chronic neuropathic pain after injury to a peripheral nerve is known to be resistant to treatment. Peripheral nerve stimulation is one of the possible treatment options, which is, however, not performed frequently. In recent years we have witnessed a renewed interest for PNS. The aim of the present study was to evaluate the long-term clinical efficacy of PNS in a group of patients with peripheral neuropathic pain treated with PNS since the 1980s.

METHODS

Of an original series of 11 patients, 5 patients could be invited for clinical examination, detailed assessment of clinical pain and QST examination. The assessments were done both during habitual use of PNS and with the stimulator off.

RESULTS

Average pain intensity and pain unpleasantness ratings as assessed with visual analog and verbal rating scales showed significant beneficial effects of PNS. Quality of life measures (sleep and daily functioning) also showed positive effects. Quantitative Sensory Testing results did not show significant differences in cold pain and heat pain thresholds between the "ON" and "OFF" conditions.

CONCLUSION

In selected patients with peripheral neuropathic pain PNS remains effective even after more than 20 years.

Migraine and the Hypothalamus

Migraine is a complex brain disorder where several neuronal pathways and neurotransmitters are involved in the pathophysiology. To search for a specific anatomical or physiological defect in migraine may be futile, but the hypothalamus, with its widespread connections with other parts of the central nervous system and its paramount control of the hypophysis and the autonomic nervous system, is a suspected locus in quo. Several lines of evidence support involvement of this small brain structure in migraine. However, whether it plays a major or minor role is unclear. The most convincing support for a pivotal role so far is the activation of the hypothalamus shown by positron emission tomography (PET) scanning during spontaneous migraine attacks. A well-known theory is that the joint effect of several triggers may cause temporary hypothalamic dysfunction, resulting in a migraine attack. If PET scanning had consistently confirmed hypothalamic activation prior to migraine headache, this hypothesis would have been supported. However, such evidence has not been provided, and the role of the hypothalamus in migraine remains puzzling. This review summarizes and discusses some of the clues.

Neurostimulation approaches to primary headache disorders

PURPOSE OF REVIEW

Conventional management options in medically intractable chronic-headache syndromes, such as chronic migraine, chronic cluster headache and hemicrania continua, are often limited. This review summarizes the current concepts, approaches and outcome data of invasive device-based neurostimulation approaches using occipital-nerve stimulation and deep-brain stimulation.

RECENT FINDINGS

Recently, there has been considerable progress in neurostimulation approaches to medically intractable chronic-headache syndromes. Previous studies have analysed the safety and efficacy of suboccipital neurostimulation in drug-resistant chronic-headache syndromes such as in chronic migraine, chronic cluster headache and hemicrania continua. The studies suggest suboccipital neurostimulation can have an effect even decades after onset of headaches, thus representing a possible therapeutic option inpatients that do not respond to any medication. Similarly, to date over 50 patients with cluster headaches underwent hypothalamic deep-brain stimulation. From these, an average of 50-70% did show a significant positive response.

SUMMARY

These findings will help to further elucidate the clinical potential of neurostimulation in chronic headache.

Advances in the basic and clinical science of migraine

Migraine continues to be an elephant in the room of medicine: massively common and a heavy burden on patients and their healthcare providers, yet the recipient of relatively little attention for research, education, and clinical resources. Its visibility is gradually increasing, however, as advances in genetics, imaging, epidemiology, and pharmacology produce a more definitive understanding of the condition, and identify more specific and effective treatments. Rapid evolution of concepts regarding its prevalence, pathophysiology, and clinical management is leading to growing recognition of migraine as a fundamentally important disorder of the nervous system.

Acute treatment of intractable migraine with sphenopalatine ganglion electrical stimulation

BACKGROUND

We report preliminary results of a novel acute treatment for intractable migraine. The sphenopalatine ganglion (SPG) has sensorimotor and autonomic components and is involved in migraine pathophysiology.

METHODS

In 11 patients with medically refractory migraine, the sphenopalatine fossa was accessed with a 20-gauge needle using the standard infrazygomatic transcoronoid approach under fluoroscopy. Patients underwent temporary unilateral electric stimulation of the SPG with a Medtronic 3057 test stimulation lead after induction of full-blown migraine. Both sham and active stimulations with different settings were carried out for < or =60 minutes, and then the lead was removed.

RESULTS

In 11 evaluations, 2 patients were pain-free within 3 minutes of stimulation. Three had pain reduction; 5 had no response; 1 was not stimulated. Five patients had no pain relief. Stimulation settings: mean amplitude of 1.2V, mean pulse rate of 67 Hz, mean pulse width of 462 micros. Lack of headache relief appeared linked to suboptimal lead placement, poor physiologic sensory response to localization stimulation, and diagnosis of medication overuse headache.

CONCLUSION

This study suggests a possible role for SPG stimulation in the treatment of refractory migraine headaches.

Neurostimulation for primary headache disorders

Neurostimulation has emerged as a potential treatment option for patients with chronic, disabling, intractable primary headache disorders. Although safety and efficacy data are limited in quantity, there is accumulating experience with the use of peripheral nerve stimulation for the treatment of intractable occipital neuralgia, cluster headache, migraine, and less common headache disorders. Deep brain stimulation has been used to treat intractable chronic cluster headache and short-lasting unilateral neuralgiform headache with conjunctival injection and tearing. This article discusses the theorized mechanisms of action of these novel treatment modalities and summarizes current knowledge regarding safety and efficacy of neurostimulation for the treatment of headache.