Cluster Headache, SUNCT, and SUNA

OBJECTIVE

This article reviews the epidemiology, clinical features, differential diagnosis, pathophysiology, and management of three types of trigeminal autonomic cephalalgias: cluster headache (the most common), short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT), and short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA).

LATEST DEVELOPMENTS

The first-line treatments for trigeminal autonomic cephalalgias have not changed in recent years: cluster headache is managed with oxygen, triptans, and verapamil, and SUNCT and SUNA are managed with lamotrigine. However, new successful clinical trials of high-dose prednisone, high-dose galcanezumab, and occipital nerve stimulation provide additional options for patients with cluster headache. Furthermore, new genetic and imaging tests in patients with cluster headache hold promise for a better understanding of its pathophysiology.

ESSENTIAL POINTS

The trigeminal autonomic cephalalgias are a group of diseases that appear similar to each other and other headache disorders but have important differences. Proper diagnosis is crucial for proper treatment.

Profile of Chinese Cluster Headache Register Individual Study (CHRIS): Clinical characteristics, diagnosis and treatment status data of 816 patients in China

BACKGROUND

The clinical profile of cluster headache may differ among different regions of the world, warranting interest in the data obtained from the initial Chinese Cluster Headache Register Individual Study (CHRIS) for better understanding.

METHODS

We conducted a multicenter, prospective, longitudinal cohort study on cluster headache across all 31 provinces of China, aiming to gather clinical characteristics, treatment approaches, imaging, electrophysiological and biological samples.

RESULTS

In total 816 patients were enrolled with a male-to-female ratio of 4.33:1. The mean age at consultation was 34.98 ± 9.91 years, and 24.89 ± 9.77 years at onset. Only 2.33% were diagnosed with chronic cluster headache, and 6.99% had a family history of the condition. The most common bout was one to two times per year (45.96%), lasting two weeks to one month (44.00%), and occurring frequently in spring (76.23%) and winter (73.04%). Of these, 68.50% experienced one to two attacks per day, with the majority lasting one to two hours (45.59%). The most common time for attacks was between 9 am and 12 pm (75.86%), followed by 1 am and 3 am (43.48%). Lacrimation (78.80%) was the most predominant autonomic symptom reported. Furthermore, 39.22% of patients experienced a delay of 10 years or more in receiving a correct diagnosis. Only 35.67% and 24.26% of patients received common acute and preventive treatments, respectively.

CONCLUSION

Due to differences in ethnicity, genetics and lifestyle conditions, CHRIS has provided valuable baseline data from China. By establishing a dynamic cohort with comprehensive multidimensional data, it aims to advance the management system for cluster headache in China.

Refractory primary and secondary headache disorders that dramatically responded to combined treatment of ultrasound-guided percutaneous suprazygomatic pterygopalatine ganglion blocks and non-invasive vagus nerve stimulation: a case series

In 1981, Devoghel achieved an 85.6% success rate in treating patients with treatment-refractory cluster headaches with alcoholization of the pterygopalatine ganglion (PPG) via the percutaneous suprazygomatic approach. Devoghel's study led to the theory that interrupting the parasympathetic pathway by blocking its transduction at the PPG could prevent or treat symptoms related to primary headache disorders (PHDs). Furthermore, non-invasive vagus nerve stimulation (nVNS) has proven to treat PHDs and has been approved by national regulatory bodies to treat, among others, cluster headaches and migraines.In this case series, nine desperate patients who presented with 11 longstanding treatment-refractory primary headache disorders and epidural blood patch-resistant postdural puncture headache (PDPH) received ultrasound-guided percutaneous suprazygomatic pterygopalatine ganglion blocks (PPGB), and seven also received nVNS. The patients were randomly selected and were not part of a research study. They experienced dramatic, immediate, satisfactory, and apparently lasting symptom resolution (at the time of the writing of this report). The report provides the case descriptions, briefly reviews the trigeminovascular and neurogenic inflammatory theories of the pathophysiology, outlines aspects of these PPGB and nVNS interventions, and argues for adopting this treatment regime as a first-line or second-line treatment rather than desperate last-line treatment of PDPH and PHDs.

Involvement of the ipsilateral-to-the-pain anterior-superior hypothalamic subunit in chronic cluster headache

BACKGROUND

Despite hypothalamus has long being considered to be involved in the pathophysiology of cluster headache, the inconsistencies of previous neuroimaging studies and a limited understanding of the hypothalamic areas involved, impede a comprehensive interpretation of its involvement in this condition.

METHODS

We used an automated algorithm to extract hypothalamic subunit volumes from 105 cluster headache patients (57 chronic and 48 episodic) and 59 healthy individuals; after correcting the measures for the respective intracranial volumes, we performed the relevant comparisons employing logist regression models. Only for subunits that emerged as abnormal, we calculated their correlation with the years of illness and the number of headache attacks per day, and the effects of lithium treatment. As a post-hoc approach, using the 7 T resting-state fMRI dataset from the Human Connectome Project, we investigated whether the observed abnormal subunit, comprising the paraventricular nucleus and preoptic area, shows robust functional connectivity with the mesocorticolimbic system, which is known to be modulated by oxytocin neurons in the paraventricular nucleus and that is is abnormal in chronic cluster headache patients.

RESULTS

Patients with chronic (but not episodic) cluster headache, compared to control participants, present an increased volume of the anterior-superior hypothalamic subunit ipsilateral to the pain, which, remarkably, also correlates significantly with the number of daily attacks. The post-hoc approach showed that this hypothalamic area presents robust functional connectivity with the mesocorticolimbic system under physiological conditions. No evidence of the effects of lithium treatment on this abnormal subunit was found.

CONCLUSIONS

We identified the ipsilateral-to-the-pain antero-superior subunit, where the paraventricular nucleus and preoptic area are located, as the key hypothalamic region of the pathophysiology of chronic cluster headache. The significant correlation between the volume of this area and the number of daily attacks crucially reinforces this interpretation. The well-known roles of the paraventricular nucleus in coordinating autonomic and neuroendocrine flow in stress adaptation and modulation of trigeminovascular mechanisms offer important insights into the understanding of the pathophysiology of cluster headache.

The Untold Story of Occipital Nerve Stimulation in Patients With Cluster Headache: Surgical Technique in Relation to Clinical Efficacy

OBJECTIVES

Approximately one in every 1000 adults experiences cluster headache (CH). Although occipital nerve stimulation (ONS) appears encouraging in treatment for most patients with refractory CH, some patients do not reach adequate pain relief with ONS. A reason for failure of ONS might be anatomical variations and different surgical approaches. Therefore, an extensive literature analysis was performed, and cadaveric experimentation was combined with our clinical experience to provide a standardized proposal for ONS and obtain optimal management of patients with refractory CH.

MATERIALS AND METHODS

Data from 36 articles published between 1998 and 2023 were analyzed to retrieve information on the anatomical landmarks and surgical technique of ONS. For the cadaveric experimentation (N = 1), two electrodes were inserted from the region over the foramen magnum and projected toward the lower third of the mastoid process.

RESULTS

The existence of multiple approaches of ONS has been confirmed by the present analysis. Discrepancies have been found in the anatomical locations and corresponding landmarks of the greater and lesser occipital nerve. The surgical approaches differed in patient positioning, electrode placement, and imaging techniques, with an overall efficacy range of 35.7% to 90%.

CONCLUSIONS

Reports on the surgical approach of ONS remain contradictory, hence emphasizing the need for standardization. Only if all implanting physicians perform the ONS surgery using a standardized protocol, can future data be combined and outcomes compared and analyzed.

Patients with chronic cluster headache may show reduced activity energy expenditure on ambulatory wrist actigraphy recordings during daytime attacks

OBJECTIVE

To investigate the changes in activity energy expenditure (AEE) throughout daytime cluster headache (CH) attacks in patients with chronic CH and to evaluate the usefulness of actigraphy as a digital biomarker of CH attacks.

BACKGROUND

CH is a primary headache disorder characterized by attacks of severe to very severe unilateral pain (orbital, supraorbital, temporal, or in any combination of these sites), with ipsilateral cranial autonomic symptoms and/or a sense of restlessness or agitation. We hypothesized increased AEE from hyperactivity during attacks measured by actigraphy.

METHODS

An observational study including patients with chronic CH was conducted. During 21 days, patients wore an actigraphy device on the nondominant wrist and recorded CH attack-related data in a dedicated smartphone application. Accelerometer data were used for the calculation of AEE before and during daytime CH attacks that occurred in ambulatory settings, and without restrictions on acute and preventive headache treatment. We compared the activity and movements during the pre-ictal, ictal, and postictal phases with data from wrist-worn actigraphy with time-concordant intervals during non-headache periods.

RESULTS

Four patients provided 34 attacks, of which 15 attacks met the eligibility criteria for further analysis. In contrast with the initial hypothesis of increased energy expenditure during CH attacks, a decrease in movement was observed during the pre-ictal phase (30 min before onset to onset) and during the headache phase. A significant decrease (p < .01) in the proportion of high-intensity movement during headache attacks, of which the majority were oxygen-treated, was observed. This trend was less present for low-intensity movements.

CONCLUSION

The unexpected decrease in AEE during the pre-ictal and headache phase of daytime CH attacks in patients with chronic CH under acute and preventive treatment in ambulatory settings has important implications for future research on wrist actigraphy in CH.

Association of Clinical and Neuroanatomic Factors With Response to Ventral Tegmental Area DBS in Chronic Cluster Headache

BACKGROUND AND OBJECTIVES

Deep brain stimulation (DBS) of the ventral tegmental area (VTA) is a surgical treatment option for selected patients with refractory chronic cluster headache (CCH). We aimed to identify clinical and structural neuroimaging factors associated with response to VTA DBS in CCH.

METHODS

This prospective observational cohort study examines consecutive patients with refractory CCH treated with VTA DBS by a multidisciplinary team in a single tertiary neuroscience center as part of usual care. Headache diaries and validated questionnaires were completed at baseline and regular follow-up intervals. All patients underwent T1-weighted structural MRI before surgery. We compared clinical features using multivariable logistic regression and neuroanatomic differences using voxel-based morphometry (VBM) between responders and nonresponders.

RESULTS

Over a 10-year period, 43 patients (mean age 53 years, SD 11.9), including 29 male patients, with a mean duration of CCH 12 years (SD 7.4), were treated and followed up for at least 1 year (mean follow-up duration 5.6 years). Overall, there was a statistically significant improvement in median attack frequency from 140 to 56 per month (Z = -4.95, p < 0.001), attack severity from 10/10 to 8/10 (Z = -4.83, p < 0.001), and duration from 110 to 60 minutes (Z = -3.48, p < 0.001). Twenty-nine (67.4%) patients experienced ≥50% improvement in attack frequency and were therefore classed as responders. There were no serious adverse events. The most common side effects were discomfort or pain around the battery site (7 patients) and transient diplopia and/or oscillopsia (6 patients). There were no differences in demographics, headache characteristics, or comorbidities between responders and nonresponders. VBM identified increased neural density in nonresponders in several brain regions, including the orbitofrontal cortex, anterior cingulate cortex, anterior insula, and amygdala, which were statistically significant (p < 0.001).

DISCUSSION

VTA DBS showed no serious adverse events, and, although there was no placebo control, was effective in approximately two-thirds of patients at long-term follow-up. This study did not reveal any reliable clinical predictors of response. However, nonresponders had increased neural density in brain regions linked to processing of pain and autonomic function, both of which are prominent in the pathophysiology of CCH.

Clinical characteristics and treatment patterns of patients with episodic cluster headache: results from the United States, United Kingdom and Germany

OBJECTIVE

To describe clinical characteristics and regional treatment patterns of episodic cluster headache (CH).

METHODS

A point-in-time survey of physicians and their patients with CH was conducted in the United States, United Kingdom and Germany in 2017.

RESULTS

Overall, 1012 patients with episodic CH were analyzed. Demographic and clinical findings were generally consistent across regions. Most patients were men (66.6%) and the mean age was 40.9 years. The greatest proportion of patients (38.3%) had ≤1 attack per day. The mean number of attacks per day (APD) was 2.4 and mean number of cluster periods per year was 2.6; the mean cluster period duration was 30.8 days. Most patients (69.3%) did not report a specific or predicable time when cluster periods occurred. Acute treatment was prescribed for 47.6% of patients, 10.3% of patients received preventive treatment, and 37.9% of patients received combined acute and preventive treatment; 4.2% of patients were not receiving treatment. Frequently prescribed acute treatments were sumatriptan, oxygen, and zolmitriptan; oxygen use varied considerably across countries and was prescribed least often in the United States. Frequently prescribed preventive treatments were verapamil, topiramate, and lithium. Lack of efficacy and tolerability were the most common reasons for discontinuing preventive treatment.

CONCLUSIONS

We observed high use of acute treatments, but only half of patients used preventive treatments despite experiencing several cluster periods per year with multiple cluster APD. Further studies about the need for and benefits of preventive treatment for episodic CH are warranted.

A prospective open label 2-8 year extension of the randomised controlled ICON trial on the long-term efficacy and safety of occipital nerve stimulation in medically intractable chronic cluster headache

BACKGROUND

We demonstrated in the randomised controlled ICON study that 48-week treatment of medically intractable chronic cluster headache (MICCH) with occipital nerve stimulation (ONS) is safe and effective. In L-ICON we prospectively evaluate its long-term effectiveness and safety.

METHODS

ICON participants were enrolled in L-ICON immediately after completing ICON. Therefore, earlier ICON participants could be followed longer than later ones. L-ICON inclusion was stopped after the last ICON participant was enrolled in L-ICON and followed for ≥2 years by completing six-monthly questionnaires on attack frequency, side effects, subjective improvement and whether they would recommend ONS to others. Primary outcome was the change in mean weekly attack frequency 2 years after completion of the ICON study compared to baseline. Missing values for log-transformed attack-frequency were imputed for up to 5 years of follow-up. Descriptive analyses are presented as (pooled) geometric or arithmetic means and 95% confidence intervals.

FINDINGS

Of 103 eligible participants, 88 (85%) gave informed consent and 73 (83%) were followed for ≥2 year, 61 (69%) ≥ 3 year, 33 (38%) ≥ 5 years and 3 (3%) ≥ 8.5 years. Mean (±SD) follow-up was 4.2 ± 2.2 years for a total of 370 person years (84% of potentially 442 years). The pooled geometric mean (95% CI) weekly attack frequency remained considerably lower after one (4.2; 2.8-6.3), two (5.1; 3.5-7.6) and five years (4.1; 3.0-5.5) compared to baseline (16.2; 14.4-18.3). Of the 49/88 (56%) ICON ≥50% responders, 35/49 (71%) retained this response and 15/39 (38%) ICON non-responders still became a ≥50% responder for at least half the follow-up period. Most participants (69/88; 78% [0.68-0.86]) reported a subjective improvement from baseline at last follow-up and 70/88 (81% [0.70-0.87]) would recommend ONS to others. Hardware-related surgery was required in 44/88 (50%) participants in 112/122 (92%) events (0.35 person-year-1 [0.28-0.41]). We didn't find predictive factors for effectiveness.

INTERPRETATION

ONS is a safe, well-tolerated and long-term effective treatment for MICCH.

FUNDING

The Netherlands Organisation for Scientific Research, the Dutch Ministry of Health, the NutsOhra Foundation from the Dutch Health Insurance Companies, and Medtronic.

Neuromodulation for the Sphenopalatine Ganglion-a Narrative Review

PURPOSE OF REVIEW

To provide an integrated overview of the current state of knowledge of neuromodulation for the sphenopalatine ganglion (SPG) by reviewing relevant and significant literature.

RECENT FINDINGS

There are several case reports and clinical trials evaluating neuromodulation for the SPG. We identified two blinded, randomized clinical trials for patients with chronic cluster headache. The randomized trials and additional studies demonstrated the long-term safety, efficacy, and cost-effectiveness of neuromodulation for the SPG. Recent studies in Europe and the USA suggest that SPG neuromodulation is a novel modality with clinical importance for treating acute cluster headaches and reducing the frequency of attacks.

The HortONS study. Treatment of chronic cluster headache with transcutaneous electrical nerve stimulation and occipital nerve stimulation: study protocol for a prospective, investigator-initiated, double-blinded, randomized, placebo-controlled trial

BACKGROUND

Chronic cluster headache (CCH) is a debilitating primary headache disorder. Occipital nerve stimulation (ONS) has shown the potential to reduce attack frequency, but the occipital paresthesia evoked by conventional (tonic) stimulation challenges a blinded comparison of active stimulation and placebo. Burst ONS offers paresthesia-free stimulation, enabling a blinded, placebo-controlled study. Identification of a feasible preoperative test would help select the best candidates for implantation. This study aims to explore ONS as a preventive treatment for CCH, comparing burst stimulation to tonic stimulation and placebo, and possibly identifying a potential preoperative predictor.

METHODS

An investigator-initiated, double-blinded, randomized, placebo-controlled trial is conducted, including 40 patients with CCH. Eligible patients complete a trial with the following elements: I) four weeks of baseline observation, II) 12 weeks of transcutaneous electrical nerve stimulation (TENS) of the occipital nerves, III) implantation of a full ONS system followed by 2 week grace period, IV) 12 weeks of blinded trial with 1:1 randomization to either placebo (deactivated ONS system) or burst (paresthesia-free) stimulation, and V) 12 weeks of tonic stimulation. The primary outcomes are the reduction in headache attack frequency with TENS and ONS and treatment safety. Secondary outcomes are treatment efficacy of burst versus tonic ONS, the feasibility of TENS as a predictor for ONS outcome, reduction in headache pain intensity (numeric rating scale), reduction in background headache, the patient's impression of change (PGIC), health-related quality of life (EuroQoL-5D), self-reported sleep quality, and symptoms of anxiety and depression (Hospital Anxiety and Depression Scale, HADS). Data on headache attack characteristics are registered weekly. Data on patient-reported outcomes are assessed after each trial phase.

DISCUSSION

The study design allows a comparison between burst ONS and placebo in refractory CCH and enables a comparison of the efficacy of burst and tonic ONS. It will provide information about the effect of burst ONS and explore whether the addition of this stimulation paradigm may improve stimulation protocols. TENS is evaluated as a feasible preoperative screening tool for ONS outcomes by comparing the effect of attack prevention of TENS and tonic ONS.

TRIAL REGISTRATION

The study is registered at Clinicaltrials.gov (trial registration number NCT05023460, registration date 07-27-2023).

Use of spinal cord stimulation in treatment of intractable headache diseases

Headache diseases remain one of the leading causes of disability in the world. With the development of neuromodulation strategies, high cervical spinal cord stimulation (hcSCS) targeting the trigeminocervical complex has been deployed to treat refractory headache diseases. In this article, we review the proposed mechanism behind hcSCS stimulation, and the various studies that have been described for the successful use of this treatment strategy in patients with chronic migraine, cluster headache, and other trigeminal autonomic cephalalgias.

European Academy of Neurology guidelines on the treatment of cluster headache

BACKGROUND AND PURPOSE

Cluster headache is a relatively rare, disabling primary headache disorder with a major impact on patients' quality of life. This work presents evidence-based recommendations for the treatment of cluster headache derived from a systematic review of the literature and consensus among a panel of experts.

METHODS

The databases PubMed (Medline), Science Citation Index, and Cochrane Library were screened for studies on the efficacy of interventions (last access July 2022). The findings in these studies were evaluated according to the recommendations of the European Academy of Neurology, and the level of evidence was established using GRADE (Grading of Recommendations Assessment, Development, and Evaluation).

RECOMMENDATIONS

For the acute treatment of cluster headache attacks, there is a strong recommendation for oxygen (100%) with a flow of at least 12 L/min over 15 min and 6 mg subcutaneous sumatriptan. Prophylaxis of cluster headache attacks with verapamil at a daily dose of at least 240 mg (maximum dose depends on efficacy and tolerability) is recommended. Corticosteroids are efficacious in cluster headache. To reach an effect, the use of at least 100 mg prednisone (or equivalent corticosteroid) given orally or at up to 500 mg iv per day over 5 days is recommended. Lithium, topiramate, and galcanezumab (only for episodic cluster headache) are recommended as alternative treatments. Noninvasive vagus nerve stimulation is efficacious in episodic but not chronic cluster headache. Greater occipital nerve block is recommended, but electrical stimulation of the greater occipital nerve is not recommended due to the side effect profile.

Current treatment options for cluster headache: limitations and the unmet need for better and specific treatments-a consensus article

AIM

Treatment for cluster headache is currently based on a trial-and-error approach. The available preventive treatment is unspecific and based on few and small studies not adhering to modern standards. Therefore, the authors collaborated to discuss acute and preventive treatment in cluster headache, addressing the unmet need of safe and tolerable preventive medication from the perspectives of people with cluster headache and society, headache specialist and cardiologist.

FINDINGS

The impact of cluster headache on personal life is substantial. Mean annual direct and indirect costs of cluster headache are more than 11,000 Euros per patient. For acute treatment, the main problems are treatment response, availability, costs and, for triptans, contraindications and the maximum use allowed. Intermediate treatment with steroids and greater occipital nerve blocks are effective but cannot be used continuously. Preventive treatment is sparsely studied and overall limited by relatively low efficacy and side effects. Neurostimulation is a relevant option for treatment-refractory chronic patients. From a cardiologist's perspective use of verapamil and triptans may be worrisome and regular follow-up is essential when using verapamil and lithium.

CONCLUSION

We find that there is a great and unmet need to pursue novel and targeted preventive modalities to suppress the horrific pain attacks for people with cluster headache.

Treatment of chronic cluster headache with burst and tonic occipital nerve stimulation: A case series

OBJECTIVES AND BACKGROUND

Chronic cluster headache (CCH) is a rare but severely debilitating primary headache condition. A growing amount of evidence suggests that occipital nerve stimulation (ONS) can offer effective treatment in patients with severe CCH for whom conventional medical therapy does not have a sufficient effect. The paresthesia evoked by conventional (tonic) stimulation can be bothersome and may thus limit therapy. Burst ONS produces paresthesia-free stimulation, but the amount of evidence on the efficacy of burst ONS as a treatment for intractable CCH is scarce.

METHODS

In this case series, we report 15 patients with CCH treated with ONS at Aarhus University Hospital, Denmark, from 2013 to 2020. Nine of these received burst stimulation either as primary treatment or as a supplement to tonic stimulation. The results were assessed in terms of the frequency of headache attacks per week and their intensity on the Numeric Rating Scale, as well as the Patient Global Impression of Change (PGIC) with ONS treatment.

RESULTS

At a median (range) follow-up of 38 (16-96) months, 12 of the 15 patients (80%) reported a reduction in attack frequency of ≥50% (a reduction from a median of 35 to 1 attack/week, p < 0.001). Seven of these patients were treated with burst ONS. A significant reduction was also seen in maximum pain intensity. Overall, 10 patients stated a clinically important improvement in their headache condition following ONS treatment, rated on the PGIC scale. A total of 16 adverse events (nine of which were in the same patient) were registered.

CONCLUSION

Occipital nerve stimulation significantly reduced the number of weekly headache attacks and their intensity. Burst ONS seems to function well alone or as a supplement to conventional tonic ONS as a preventive treatment for CCH; however, larger prospective studies are needed to determine whether the effect can be confirmed and whether the efficacy of the two stimulation paradigms is even.

Management of cluster headache: Treatments and their mechanisms

BACKGROUND

The management of cluster headache is similar to that of other primary headache disorders and can be broadly divided into acute and preventive treatments. Acute treatments for cluster headache are primarily delivered via rapid, non-oral routes (such as inhalation, nasal, or subcutaneous) while preventives include a variety of unrelated treatments such as corticosteroids, verapamil, and galcanezumab. Neuromodulation is becoming an increasingly popular option, both non-invasively such as vagus nerve stimulation when medical treatment is contraindicated or side effects are intolerable, and invasively such as occipital nerve stimulation when medical treatment is ineffective. Clinically, this collection of treatment types provides a range of options for the informed clinician. Scientifically, this collection provides important insights into disease mechanisms.

METHODS

Two authors performed independent narrative reviews of the literature on guideline recommendations, clinical trials, real-world data, and mechanistic studies.

RESULTS

Cluster headache is treated with acute treatments, bridge treatments, and preventive treatments. Common first-line treatments include subcutaneous sumatriptan and high-flow oxygen as acute treatments, corticosteroids (oral or suboccipital injections) as bridge treatments, and verapamil as a preventive treatment. Some newer acute (non-invasive vagus nerve stimulation) and preventive (galcanezumab) treatments have excellent clinical trial data for episodic cluster headache, while other newer treatments (occipital nerve stimulation) have been specifically tested in treatment-refractory chronic cluster headache. Most treatments are suspected to act on the trigeminovascular system, the autonomic system, or the hypothalamus.

CONCLUSIONS

The first-line treatments have not changed in recent years, but new treatments have provided additional options for patients.

Deep Brain Stimulation for Chronic Cluster Headaches: A Systematic Review and Meta-Analysis

BACKGROUND

Chronic cluster headache (CCH) is a severe and debilitating sub-type of trigeminal autonomic cephalalgia that can be resistant to medical management and associated with significant impairment in quality of life. Studies of deep brain stimulation (DBS) for CCH have provided promising results but have not been assessed in a comprehensive systematic review/meta-analysis.

OBJECTIVE

The objective was to perform a systematic literature review and meta-analysis of patients with CCH treated with DBS to provide insight on safety and efficacy.

METHODS

A systematic review and meta-analysis were performed according to PRISMA 2020 guidelines. 16 studies were included in final analysis. A random-effects model was used to meta-analyze data.

RESULTS

Sixteen studies reported 108 cases for data extraction and analysis. DBS was feasible in >99% of cases and was performed either awake or asleep. Meta-analysis revealed that the mean difference in headache attack frequency and headache intensity after DBS were statistically significant (p < 0.0001). Utilization of microelectrode recording was associated with statistically significant improvement in headache intensity postoperatively (p = 0.006). The average overall follow-up period was 45.4 months and ranged from 1 to 144 months. Death occurred in <1%. The rate of major complications was 16.67%.

CONCLUSIONS

DBS for CCHs is a feasible surgical technique with a reasonable safety profile that can be successfully performed either awake or asleep. In carefully selected patients, approximately 70% of patients achieve excellent control of their headaches.

Management of Trigeminal Autonomic Cephalalgias Including Chronic Cluster: A Review

Importance

Trigeminal autonomic cephalalgias (TACs) comprise a unique collection of primary headache disorders characterized by moderate or severe unilateral pain, localized in in the area of distribution of the first branch of the trigeminal nerve, accompanied by cranial autonomic symptoms and signs. Most TACs are rare diseases, which hampers the possibility of performing randomized clinical trials and large studies. Therefore, knowledge of treatment efficacy must be based only on observational studies, rare disease registries, and case reports, where real-world data and evidence play an important role in health care decisions.

Observations

Chronic cluster headache is the most common of these disorders, and the literature offers some evidence from randomized clinical trials to support the use of pharmacologic and neurostimulation treatments. Galcanezumab, a monoclonal antibody targeting the calcitonin gene-related peptide, was not effective at 3 months in a randomized clinical trial but showed efficacy at 12 months in a large case series. For the other TACs (ie, paroxysmal hemicrania, hemicrania continua, short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing, and short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms), only case reports and case series are available to guide physicians in everyday management.

Conclusions and Relevance

The accumulation of epidemiologic, pathophysiologic, natural history knowledge, and data from case series and small controlled trials, especially over the past 20 years from investigators around the world, has added to the previously limited evidence and has helped advance and inform the treatment approach to rare TACs, which can be extremely challenging for clinicians.

Symptoms and pathophysiology of cluster headache. Approach to combined occipital and supraorbital neurostimulation

Cluster headache (CH) is included under section 3 - Trigeminal autonomic cephalalgias (TAC) of the International Headache Society (IHS) classification. It is one of the most frequent, painful and disabling primary headaches. Acute and preventive pharmacological treatments are often poorly tolerated and of limited effectiveness. Due to improved understanding of the pathophysiology of CH, neuromodulation devices are now considered safe and effective options for preventive and acute treatment of CH. In this paper, we review the information available to date, and present the case of a patient with disabling cluster headache highly resistant to medical treatment who underwent implantation of a peripheral nerve neurostimulation system to stimulate the supraorbital nerves (SON) and greater occipital nerve (GON) in our Pain Unit. We also review the diagnostic criteria for CH, the state of the knowledge on the pathophysiology of CH, and the role played by neuromodulation in treating this condition.

Clinical Profile of Chronic Cluster Headaches in a Regional Headache Center in Japan

Objective Little is known about the prevalence and characteristics of chronic cluster headache (CCH) in Japan. We therefore characterized the clinical profile of CCH in Japan by surveying patients with CCH who were registered at a Japanese regional headache center. We also reviewed the existing literature for the prevalence and clinical characteristics of CCH reported in various populations. Methods In this single-center retrospective study, we assessed consecutive patients with cluster headache (CH) who visited a regional tertiary headache center between February 2011 and July 2020. They were treated following the Clinical Practice Guideline for Chronic Headache 2013. We compared their demographic characteristics and clinical features according to the CCH onset pattern (primary vs. secondary). Results Of 420 patients with CH, 19 (4.2%) had CCH (9 primary and 10 secondary). The incidence of CCH in Japan is relatively low compared to that in Western countries but is comparable to that in other Asian countries. CCH showed a higher predominance of men than women. Compared to primary CCH, secondary CCH included a higher proportion of current smokers and older patients during clinic visits. Subcutaneous sumatriptan and oxygen inhalation were the most common abortive treatments, and oral prednisolone and verapamil were the most common preventive treatments. Home oxygen therapy was effective in six of seven patients. Only two patients with coexisting migraine received calcitonin gene-related peptide (CGRP)-targeted therapies. Conclusions CCH remains refractory to treatment. Improving treatment outcomes will require maximizing the use of currently available drugs and expanding the use of neuromodulation, nerve block, and CGRP-targeted therapies.

Cluster headache: A review of clinical presentation, evaluation, and management

ABSTRACT

Cluster headache is a primary headache disorder that leads to attacks of excruciating unilateral head pain with ipsilateral cranial autonomic features. These attacks can cluster, with frequent occurrences for weeks or months at a time followed by a period of complete remission. The excruciating pain of these attacks often is accompanied by increased suicidality, delays in diagnosis, and unnecessary invasive interventions. This article reviews the clinical presentation, differential diagnosis, evaluation, and treatment of cluster headache.

Anatomy and Physiology of Headache

Headache disorders can produce recurrent, incapacitating pain. Migraine and cluster headache are notable for their ability to produce significant disability. The anatomy and physiology of headache disorders is fundamental to evolving treatment approaches and research priorities. Key concepts in headache mechanisms include activation and sensitization of trigeminovascular, brainstem, thalamic, and hypothalamic neurons; modulation of cortical brain regions; and activation of descending pain circuits. This review will examine the relevant anatomy of the trigeminal, brainstem, subcortical, and cortical brain regions and concepts related to the pathophysiology of migraine and cluster headache disorders.

[Acupuncture at sphenopalatine ganglion combined with conventional acupuncture for episodic cluster headache: a randomized controlled trial]

OBJECTIVE

To observe the clinical effect of acupuncture at sphenopalatine ganglion combined with conventional acupuncture for episodic cluster headache (CH).

METHODS

One hundred and eighty patients with episodic CH were randomly divided into a combined group (60 cases, 3 cases dropped off)，an acupuncture group (60 cases, 2 cases dropped off) and a sphenopalatine ganglion group (60 cases, 2 cases dropped off and 1 case was removed). The patients in the acupuncture group were treated with conventional acupuncture at Touwei (ST 8), Yintang (GV 24⁺), Yangbai (GB 14), Hegu (LI 4), etc., once a day, 6 times a week. The patients in the sphenopalatine ganglion group were treated with acupuncture at sphenopalatine ganglion, once every other day, 3 times a week. On the basis of the conventional acupuncture, the combined group was treated with acupuncture at sphenopalatine ganglion once every other day. Two weeks were taken as a course of treatment, and 3 courses of treatment were required in the 3 groups. The score of visual analogue scale (VAS), the number of headache attacks per week, the duration of each headache attack and the score of migraine-specific quality of life questionnaire version 2.1 (MSQ) were observed before and after treatment and in follow-up of 3 months after treatment. The clinical efficacy of each group was compared.

RESULTS

After treatment and in follow-up, the VAS score of headache, the number of headache attacks per week, the duration of each headache attack, and each various scores and the total score of MSQ of each group were lower than those before treatment (P<0.01). Except that the number of headache attacks per week in the combined group was lower than the sphenopalatine ganglion group (P<0.01), other indexes in the combined group were lower than the other two groups (P<0.05, P<0.01). The total effective rate in the combined group was 93.0% (53/57), which was higher than 75.9% (44/58) in the acupuncture group and 73.7% (42/57) in the sphenopalatine ganglion group（P<0.05, P<0.01).

CONCLUSION

Acupuncture at sphenopalatine ganglion combined with conventional acupuncture could reduce the degree of pain in patients with episodic CH, reduce the number and duration of headache attacks, and improve the quality of life of patients. It is more effective than simple conventional acupuncture or acupuncture at sphenopalatine ganglion alone.

Recent advances in the diagnosis and management of cluster headache

Cluster headache, a primary headache disorder, consists of short (15-180 minutes), frequent (up to eight a day), unilateral attacks of facial pain with associated ipsilateral autonomic features and restlessness. The attacks are suspected to be one of the most painful human experiences, and the disorder is associated with a high rate of suicidal ideation. Proper diagnosis is key, as some of the most effective treatments, such as high flow oxygen gas, are rarely used in other headache disorders. Yet diagnostic delay is typically years for this disorder, as it is often confused with migraine and trigeminal neuralgia, and secondary causes may be overlooked. This review covers the clinical, pathophysiologic, and therapeutic features of cluster headache. Recent updates in diagnosis include the redefinition of chronic cluster headache (remission periods lasting less than three months instead of the previous one month), and recent advances in management include new treatments for episodic cluster headache (galcanezumab and non-invasive vagus nerve stimulation).

[Autonomic Disorders in Trigeminal Autonomic Cephalalgias: An Update]

The term trigeminal autonomic cephalalgias (TACs) was introduced in the 2^nd edition of the International Classification of Headache Disorders, and has been retained in the 3^rd edition. TACs include cluster headache, paroxysmal hemicrania, short-lasting unilateral neuralgiform headache attacks, hemicrania continua, and probable trigeminal autonomic cephalalgia. Headaches classified as TACs share clinical features with unilateral headache and usually present with prominent lateralized and ipsilateral cranial parasympathetic autonomic features, including the following: (1) conjunctival injection and/or lacrimation, (2) nasal congestion and/or rhinorrhea, (3) eyelid edema, (4) forehead and facial sweating, (5) miosis and/or ptosis. "Clinical Practice Guideline for Headache 2021 (Japanese version)" will serve as a useful aid for diagnosis and treatment of TACs. Currently, hypothalamic activation, activation of the trigeminal-autonomic nerve reflex, internal carotid artery dilatation, and the action of some neuropeptides are implicated as pathophysiological mechanisms underlying TACs; however, it is not unequivocal. Further studies are warranted to gain deeper insight into several unclear aspects associated with TACs.

Refractory Orofacial Pain: Is It the Patient or the Pain?

AIMS

To highlight and discuss the term "refractory" when used to describe pain conditions and its application to orofacial pain, as well as to highlight the factors that must be considered in a refractory patient.

METHODS

A scoping review of recent publications (2010 to 2021) applying the term "refractory" to orofacial pain was conducted, and this paper presents their limitations and definitions.

RESULTS

The term "refractory" is often used to describe pain instead of "persistent" or "nonresponsive." There are clear definitions in the use of refractory for migraine, cluster headaches, and other nonheadache disorders. Currently, the term is applied to pain conditions in order to alter the patient pathway of treatment, sometimes to escalate a patient from one care sector to another and sometimes to escalate treatment to more costly surgical interventional techniques.

CONCLUSION

There is a need for a clear definition for use of the term "refractory" in orofacial pain conditions, excluding migraine and cluster headaches. In addition, there is a requirement for a consensus on the implications of the use of refractory when assessing and managing patients.

Cluster Headache: Rapid Evidence Review

Cluster headache, the most common form of trigeminal autonomic cephalgia, is a rare primary headache disorder that affects less than 1% of the population. The mean age of onset is 30 years, and it is two to three times more common in males. Cluster headache consists of attacks of severe unilateral pain located in the orbital, supraorbital, and/or temporal region that occur from every other day up to eight times per day and last from 15 to 180 minutes. The pain is associated with ipsilateral autonomic symptoms (most commonly lacrimation, conjunctival injection, nasal congestion or rhinorrhea, ptosis, edema of the eyelid, sweating of the forehead or face, and miosis) and a sense of agitation or restlessness. Attacks occur in clusters, called bouts, and are episodic or chronic. Common triggers include alcohol, nitroglycerin, food containing nitrates, and strong odors. Abortive treatments include triptans and oxygen; transitional treatments include steroids and suboccipital steroid injections; and prophylactic treatments include verapamil, lithium, melatonin, and topiramate. Newer treatments for cluster headache include galcanezumab, neurostimulation, and somatostatin receptor agonists.

Cluster Headache and Other Trigeminal Autonomic Cephalalgias

PURPOSE OF REVIEW

The trigeminal autonomic cephalalgias (TACs) are relatively rare, but they represent a distinct set of syndromes that are important to recognize. Despite their unique features, TACs often go undiagnosed or misdiagnosed for several years, leading to unnecessary pain and suffering. A significant proportion of TAC presentations may have secondary causes.

RECENT FINDINGS

The underlying pathophysiology of TACs is likely rooted in hypothalamic dysfunction and derangements in the interplay of circuitry involving trigeminovascular, trigeminocervical, trigeminoautonomic, circadian, and nociceptive systems. Recent therapeutic advancements include a better understanding of how to use older therapies more effectively and the identification of new approaches.

SUMMARY

TAC syndromes are rare but important to recognize because of their debilitating nature and greater likelihood for having potentially serious underlying causes. Although treatment options have remained somewhat limited, scientific inquiry is continually advancing our understanding of these syndromes and how best to manage them.

Cluster headache and TACs: state of the art

Cluster headache (CH), paroxysmal hemicrania (PH), short-lasting unilateral neuralgiform headache attacks (including SUNCT and SUNA), and hemicrania continua (HC) compose the group of trigeminal autonomic cephalalgias (TACs). Here, we review the recent advances in the field and summarize the current knowledge about the origin of these headaches. Similar to the other primary headaches, the pathogenesis is still much obscure. However, advances are being made in both animal models and humans studies. Three structures clearly appear to be crucial in the pathophysiology of TACs: the trigeminal nerve, the facial parasympathetic system, and the hypothalamus. The physiologic and pathologic functioning of each of these elements and their interactions is being progressively clarified, but critical questions are still open.

[Non-Invasive Neuromodulation for the Treatment of Migraine and Cluster Headache]

Migraine and cluster headache are common headache disorders that impact patients' quality of life. The pharmacotherapy for acute headache attacks is sometimes ineffective, and the adherence to preventive medications is low due to their side effects and/or lack of efficacy. Recently, several non-invasive neuromodulation devices for primary headache disorders have been launched and attracted the attention of patients and physicians because of their practicality, safety, and the possibility of becoming new treatment options. In this review, we describe external trigeminal nerve stimulation (eTNS), non-invasive vagal nerve stimulation (nVNS), and single-pulse transcranial magnetic stimulation (sTMS) which have been well studied in recent randomized sham-controlled trials and open-label studies. We also describe their mechanisms of action and adverse events.

[Cluster headache and other trigeminal autonomic cephalalgias]

Trigeminal autonomic cephalalgias (TACs) are a group of 4 different primary headache syndromes that have a lot of pathophysiological and clinical features in common. The 4 different TACs are: cluster headache, paroxysmal hemicrania, short-lasting unilateral neuralgiform headache attacks and hemicrania continua. TACs are characterized by frequent, strictly unilateral, (very) intense headache attacks with ipsilateral cranial autonomic symptoms or intrinsic restlessness or both. A distinction can be made between the 4 TACs on the basis of the duration and frequency of the headache attacks. The treatment of cluster headache consists of an acute treatment and a maintenance treatment. Headache attacks in the context of paroxysmal hemicrania and hemicrania continua (almost) always respond to treatment with indomethacin. More and more neuromodulation therapies are becoming available, such as vagus nerve stimulation, stimulation and blocking of the sphenopalatine ganglion, stimulation and blocking of the occipital nerve and deep brain stimulation.

Managing cluster headache

Cluster headache is a neurological disorder that presents with unilateral severe headache associated with ipsilateral cranial autonomic symptoms. Cluster headache attacks often occur more than once a day, and typically manifesting in bouts. It has a point prevalence of 1 in 1000 and is the most common trigeminal autonomic cephalalgia. This article aims to guide general neurologists to an accurate diagnosis and practical management options for cluster headache patients.

Burst Occipital Nerve Stimulation for Chronic Migraine and Chronic Cluster Headache

BACKGROUND

Occipital nerve stimulation (ONS) is widely used for headache syndromes including chronic migraine (CM) and chronic cluster headache (CCH). The paraesthesia associated with tonic stimulation can be bothersome and can limit therapy. It is now clear in spinal cord stimulation that paraesthesia-free waveforms can produce effective analgesia, but this has not been reported in ONS for CM or CCH.

MATERIALS AND METHODS

Seventeen patients (12 CM and 5 CCH) were treated with bilateral burst pattern ONS, including 4 who had previously had tonic ONS. Results were assessed in terms of the frequency of headaches (number of headache days per month for CM, and number of attacks per day for CCH) and their intensity on the numeric pain rating scale.

RESULTS

Burst ONS produced a statistically significant mean reduction of 10.2 headache days per month in CM. In CCH, there were significant mean reductions in headache frequency (92%) and intensity (42%).

CONCLUSION

Paraesthesia is not necessary for good quality analgesia in ONS. Larger studies will be required to determine whether the efficacies of the two stimulation modes differ. Burst ONS is imperceptible and therefore potentially amenable to robustly blinded clinical trials.

Non-invasive neuromodulation for migraine and cluster headache: a systematic review of clinical trials

Non-invasive neuromodulation therapies for migraine and cluster headache are a practical and safe alternative to pharmacologics. Comparisons of these therapies are difficult because of the heterogeneity in study designs. In this systematic review of clinical trials, the scientific rigour and clinical relevance of the available data were assessed to inform clinical decisions about non-invasive neuromodulation. PubMed, Cochrane Library and ClinicalTrials.gov databases and the WHO's International Clinical Trials Registry Platform were searched for relevant clinical studies of non-invasive neuromodulation devices for migraine and cluster headache (1 January 1990 to 31 January 2018), and 71 were identified. This analysis compared study designs using recommendations of the International Headache Society for pharmacological clinical trials, the only available guidelines for migraine and cluster headache. Non-invasive vagus nerve stimulation (nVNS), single-transcranial magnetic stimulation and external trigeminal nerve stimulation (all with regulatory clearance) were well studied compared with the other devices, for which studies frequently lacked proper blinding, sham controls and sufficient population sizes. nVNS studies demonstrated the most consistent adherence to available guidelines. Studies of all neuromodulation devices should strive to achieve the same high level of scientific rigour to allow for proper comparison across devices. Device-specific guidelines for migraine and cluster headache will be soon available, but adherence to current guidelines for pharmacological trials will remain a key consideration for investigators and clinicians.

Multicentre, prospective, randomised, controlled, blinded-endpoint study to evaluate the efficacy and safety of pterygopalatine ganglion pulsed radiofrequency treatment for cluster headache: study protocol

INTRODUCTION

Single-centre reports on small groups of patients have shown that pterygopalatine ganglion pulsed radiofrequency treatment in patients with refractory cluster headache (CH) can quickly relieve pain without significant side effects. However, a randomised controlled trial is still necessary to evaluate whether pterygopalatine ganglion pulsed radiofrequency (PRF) treatment is a viable treatment option for patients with CH who are not responding to drug treatment.

METHODS AND ANALYSIS

This investigation is a multicentre, prospective, randomised, controlled, blinded-endpoint study. We will enrol 80 patients with CH who are not responding to medication. The enrolled patients will be randomly divided into two groups: the nerve block (NB) group and the PRF group. All patients will undergo CT-guided pterygopalatine ganglion puncture. A mixture containing steroids and local anaesthetics will be slowly injected into the patients in the NB group. The patients in the PRF group will be treated with PRF at 42°C for 360 s. After treatment, the duration of cluster periods; degree of pain during headache attacks; frequency of headache attacks; duration of each headache attack; dose of auxiliary analgesic drugs; duration of remission; degree of patient satisfaction; effectiveness rates at 1 day, 3 days, 1 week, 2 weeks, 1 month, 3 months, 6 months, and 1 year after the procedure; and intraoperative and postoperative adverse events will be compared between the two groups.

ETHICS AND DISSEMINATION

This study was approved by the institutional ethics committee of the Beijing Tiantan Hospital (approval number: KY 2018-027-02). The results of the study will be published in peer-reviewed journals, and the findings will be presented at scientific meetings.

TRIAL REGISTRATION NUMBER

NCT03567590; Pre-results.

Effectiveness of Oxygen and Other Acute Treatments for Cluster Headache: Results From the Cluster Headache Questionnaire, an International Survey

OBJECTIVE

To assess the effectiveness and adverse effects of acute cluster headache medications in a large international sample, including recommended treatments such as oxygen, commonly used medications such as opioids, and emerging medications such as intranasal ketamine. Particular focus is paid to a large subset of respondents 65 years of age or older.

BACKGROUND

Large international surveys of cluster headache are rare, as are examinations of treatments and side effects in older cluster headache patients. This article presents data from the Cluster Headache Questionnaire, with respondents from over 50 countries and with the vast majority from the United States, the United Kingdom, and Canada.

METHODS

This internet-based survey included questions on cluster headache diagnostic criteria, which were used as part of the inclusion/exclusion criteria for the study, as well as effectiveness of medications, physical and medical complications, psychological and emotional complications, mood scores, and difficulty obtaining medications. The diagnostic questions were also used to create a separate group of respondents with probable cluster headache. Limitations to the methods include the use of nonvalidated questions, the lack of a formal clinical diagnosis of cluster headache, and the grouping of some medications (eg, all triptans as opposed to sumatriptan subcutaneous alone).

RESULTS

A total of 3251 subjects participated in the questionnaire, and 2193 respondents met criteria for this study (1604 cluster headache and 589 probable cluster headache). Of the respondents with cluster headache, 68.8% (1104/1604) were male and 78.0% (1245/1596) had episodic cluster headache. Over half of respondents reported complete or very effective treatment for triptans (54%, 639/1139) and oxygen (54%, 582/1082). Between 14 and 25% of respondents reported complete or very effective treatment for ergot derivatives (dihydroergotamine 25%, 42/170; cafergot/ergotamine 17%, 50/303), caffeine and energy drinks (17%, 7/41), and intranasal ketamine (14%, 5/37). Less than 10% reported complete or very effective treatment for opioids (6%, 30/541), intranasal capsaicin (5%, 7/151), and intranasal lidocaine (2%, 5/241). Adverse events were especially low for oxygen (no or minimal physical and medical complications 99%, 1077/1093; no or minimal psychological and emotional complications 97%, 1065/1093), intranasal lidocaine (no or minimal physical and medical complications 97%, 248/257; no or minimal psychological and emotional complications 98%, 251/257), intranasal ketamine (no or minimal physical and medical complications 95%, 38/40; no or minimal psychological and emotional complications 98%, 39/40), intranasal capsaicin (no or minimal physical and medical complications 91%, 145/159; no or minimal psychological and emotional complications 94%, 150/159), and caffeine and energy drinks (no or minimal physical and medical complications 89%, 39/44; no or minimal psychological and emotional complications 91%, 40/44). This is in comparison to ergotamine/cafergot (no or minimal physical and medical complications 83%, 273/327; no or minimal psychological and emotional complications 89%, 290/327), dihydroergotamine (no or minimal physical and medical complications 81%, 143/176; no or minimal psychological and emotional complications 91%, 160/176), opioids (no or minimal physical and medical complications 76%, 416/549; no or minimal psychological and emotional complications 77%, 423/549), or triptans (no or minimal physical and medical complications 73%, 883/1218; no or minimal psychological and emotional complications 85%, 1032/1218). A total of 139 of 1604 cluster headache respondents (8.7%) were age 65 and older and reported similar effectiveness and adverse events to the general population. The 589 respondents with probable cluster headache reported similar medication effectiveness to respondents with a full diagnosis of cluster headache.

CONCLUSIONS

Oxygen is reported by survey respondents to be a highly effective treatment with few complications in cluster headache in a large international sample, including those 65 years or over. Triptans are also very effective with some side effects, and newer medications deserve additional study. Patients with probable cluster headache may respond similarly to acute medications as patients with a full diagnosis of cluster headache.

Review of evidence on noninvasive vagus nerve stimulation for treatment of migraine: efficacy, safety, and implications

GammaCore was cleared by the FDA for the acute treatment of episodic migraine and episodic cluster headache and has 5 Conformité Européenne marks. Data indicate that gammaCore treatment is both safe and effective as an acute treatment for migraine. Current reimbursement policies need to be updated based on the growing body of evidence to reflect the established status of gammaCore that is no longer experimental. GammaCore provides substantial value to patients and to payers for consideration for pay-for-performance health coverage strategies and policies.

Noninvasive vagus nerve stimulation in a primary care setting: effects on quality of life and utilization measures in multimorbidity patients with or without primary headache

A patient audit was conducted in the UK to evaluate the impact of gammaCore use in multimorbidity patients on quality of life and healthcare resources utilization measures. A total of 233 patients were enrolled and their data was examined over a 1-year period after their gammaCore prescription. Of these patients, 132 (56%) had primary headache disorders while 101 (44%) were patients without a headache disorder (nonheadache patients). The mean age was 49 years, 169 (72%) were female, the mean number of comorbid conditions was 3.1, and the mean baseline EQ-5D score was 0.581. The mean paired difference in EQ-5D index for persistent gammaCore users (ie patients who used gammaCore for at least 40 weeks) was +0.156 at week 40. The mean percentage reductions in number of general practice consults (doctor's office appointments) was -28.5% from baseline mean of 7.31 and, 40.0% from baseline mean of 3.52 for medical codes used. This evidence demonstrates that a significant proportion of these multimorbidity patients on gammaCore remained compliant with the prescribed treatment regimen for an extended period. GammaCore use in multimorbidity patients may be associated with lower costs of care and provide opportunities for pay-for-performance coverage policies.

Cost-effectiveness of noninvasive vagus nerve stimulation for acute treatment of episodic migraine and role in treatment sequence strategies

Migraine affects 15% of the population in the United States and is associated with comorbidities, with an estimated economic burden of $78 billion annually. GammaCore is used adjunctively with current standard of care and abortive medications and has shown to be superior in acute treatment of episodic migraine compared to sham. However, the economic impact has not been characterized for this indication. We conducted a cost-effectiveness analyses for 2 hypothetical scenarios: a primary model for treatment options gammaCore plus standard of care compared to standard of care alone for acute treatment of migraine; and a secondary model for treatment sequence strategies where acute treatment with gammaCore or standard of care each prior to erenumab prevention compared to initiating erenumab prevention with no prerequisite. The time horizon for the model is 1 year, using a payer perspective. GammaCore plus standard of care arm was dominant over standard of care alone in the primary model. The mean costs for gammaCore plus standard of care arm and standard of care individually were $9678 and $10,010, respectively. The mean quality of life-years for gammaCore plus standard of care arm and standard of care alone were 0.67, and 0.63, respectively. For the secondary model, the mean costs for gammaCore followed by erenumab, standard of care followed by erenumab and initiating with erenumab with no prior gammaCore or standard of care treatment were $10,678, $11,583, and $13,766. The corresponding mean for quality of life-years were 0.70, 0.67, and 0.65, respectively. For gammaCore dominance, ie, in this scenario, patients were more satisfied on gammaCore, to not need erenumab for preventative therapy lower mean costs and represents savings for payers. This was driven by efficacy, improvement in quality of life, and reduction in costs of care associated with successful treatment of migraine attacks. These findings provide new economic evidence to support value forcoverage for gammaCore.

Male and female sex hormones in primary headaches

BACKGROUND

The three primary headaches, tension-type headache, migraine and cluster headache, occur in both genders, but all seem to have a sex-specific prevalence. These gender differences suggest that both male and female sex hormones could have an influence on the course of primary headaches. This review aims to summarise the most relevant and recent literature on this topic.

METHODS

Two independent reviewers searched PUBMED in a systematic manner. Search strings were composed using the terms LH, FSH, progesteron*, estrogen*, DHEA*, prolactin, testosterone, androgen*, headach*, migrain*, "tension type" or cluster. A timeframe was set limiting the search to articles published in the last 20 years, after January 1st 1997.

RESULTS

Migraine tends to follow a classic temporal pattern throughout a woman's life corresponding to the fluctuation of estrogen in the different reproductive stages. The estrogen withdrawal hypothesis forms the basis for most of the assumptions made on this behalf. The role of other hormones as well as the importance of sex hormones in other primary headaches is far less studied.

CONCLUSION

The available literature mainly covers the role of sex hormones in migraine in women. Detailed studies especially in the elderly of both sexes and in cluster headache and tension-type headache are warranted to fully elucidate the role of these hormones in all primary headaches.

Primary Headaches

The primary headaches are composed of multiple entities that cause episodic and chronic head pain in the absence of an underlying pathologic process, disease, or traumatic injury. The most common of these are migraine, tension-type headache, and the trigeminal autonomic cephalalgias. This article reviews the clinical presentation, pathophysiology, and treatment of each to help in differential diagnosis. These headache types share many common signs and symptoms, thus a clear understanding of each helps prevent a delay in diagnosis and inappropriate or ineffective treatment. Many of these patients seek dental care because orofacial pain is a common presenting symptom.

Anodal frontal tDCS for chronic cluster headache treatment: a proof-of-concept trial targeting the anterior cingulate cortex and searching for nociceptive correlates

BACKGROUND

Percutaneous occipital nerve stimulation (ONS) is effective in refractory chronic cluster headache (rCCH) patients. Responders to ONS differ from non-responders by greater glucose metabolism in subgenual anterior cingulate cortex (sgACC). We reasoned that transcranial direct current stimulation (tDCS), a non-invasive approach, might be able to activate this area and thus improve rCCH patients. Our objective was to explore in a pilot trial the therapeutic potential of tDCS (anode at Fz, cathode over C7) and its possible effects on pain perception, frontal executive functions and mood in rCCH patients.

METHODS

Thirty-one patients were asked to apply daily 20-min sessions of 2 mA tDCS for 4 or 8 weeks after a 1-month baseline. CH attacks were monitored with paper diaries. The primary outcome measure was change in weekly attacks between baseline and the last week of tDCS. Twenty-three patients were available for a modified ITT analysis, 21 for per-protocol analysis. We also explored treatment-related changes in thermal pain thresholds and nociceptive blink reflexes (nBR), frontal lobe function and mood scales.

RESULTS

In the per-protocol analysis there was a mean 35% decrease of attack frequency (p = 0.0001) with 41% of patients having a ≥ 50% decrease. Attack duration and intensity were also significantly reduced. After 8 weeks (n = 10), the 50% responder rate was 45%, but at follow-up 2 weeks after tDCS (n = 16) mean attack frequency had returned to baseline levels. The treatment effect was significant in patients with high baseline thermal pain thresholds in the forehead (n = 12), but not in those with low thresholds (n = 9). The Frontal Assessment Battery score increased after tDCS (p = 0.01), while there was no change in depression scores or nBR.

CONCLUSION

tDCS with a Fz-C7 montage may have a preventive effect in rCCH patients, especially those with low pain sensitivity, suggesting that a sham-controlled trial in cluster headache is worthwhile. Whether the therapeutic effect is due to activation of the sgACC that can in theory be reached by the electrical field, or of other prefrontal cortical areas remains to be determined.

Cluster Headache and Other Trigeminal Autonomic Cephalalgias

PURPOSE OF REVIEW

This article covers the clinical features, differential diagnosis, and management of the trigeminal autonomic cephalalgias (TACs). The TACs are composed of five diseases: cluster headache, paroxysmal hemicrania, short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT), short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA), and hemicrania continua.

RECENT FINDINGS

New classifications for the TACs have two important updates; chronic cluster headache is now defined as remission periods lasting less than 3 months (formerly less than 1 month), and hemicrania continua is now classified as a TAC (formerly classified as other primary headache). The first-line treatments of TACs have not changed in recent years: cluster headache is managed with oxygen, triptans, and verapamil; paroxysmal hemicrania and hemicrania continua are managed with indomethacin; and SUNCT and SUNA are managed with lamotrigine. However, advancements in neuromodulation have recently provided additional options for patients with cluster headache, which include noninvasive devices for abortive therapy and invasive devices for refractory cluster headache. Patient selection for these devices is key.

SUMMARY

The TACs are a group of diseases that appear similar to each other and to other headache disorders but have important differences. Proper diagnosis is crucial for proper treatment. This article reviews the pathophysiology, epidemiology, differential diagnosis, and treatment of the TACs.