Manjit Matharu

Posterior hypothalamic and brainstem activation in hemicrania continua

Objective.—To determine the brain structures involved in mediating the pain of hemicrania continua using positron emission tomography.

Management of Trigeminal Autonomic Cephalgias and Hemicrania Continua

The trigeminal autonomic cephalgias (TACs) are a group of primary headache disorders characterised by unilateral trigeminal distribution pain that occurs in association with ipsilateral cranial autonomic features. This group of headache disorders includes cluster headache, paroxysmal hemicrania and short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT syndrome). Although hemicrania continua has previously been classified amongst the TACs, its nosological status remains unclear. Despite their similarities, these disorders differ in their clinical manifestations and response to therapy, thus underpinning the importance of recognising them. We have outlined the clinical manifestations, differential diagnoses, diagnostic workup and the treatment options for each of these syndromes.

Subcutaneous octreotide in cluster headache: Randomized placebo‐controlled double‐blind crossover study

Current practical evidence‐based acute treatments of cluster headache are limited to subcutaneous and intranasal formulations of sumatriptan, and oxygen. Two small randomized, double‐blind trials suggested efficacy of somatostatin in cluster headache. We sought to determine whether octreotide, a somatostatin analog, is effective in the abortive treatment of acute cluster headache. Patients with episodic and chronic cluster headache, as defined by the International Headache Society, were recruited to a double‐blind placebo‐controlled crossover study. Patients were instructed to treat two attacks of at least moderate pain severity, with at least a 24‐hour break, using subcutaneous octreotide μg or matching placebo. The primary end point was the headache response defined as very severe, severe, or moderate pain becomes mild or nil, at 30 minutes. The primary end point was examined using a multilevel analysis approach. A total of 57 patients were recruited of whom 46 provided efficacy data on attacks treated with octreotide and 45 with placebo. The headache response rate with subcutaneous octreotide was 52%, whereas that with placebo was 36%. Modeling the treatment outcome as a binomial where response was determined by treatment, using the patient as the level 2 variable, and considering period effect, sex, and cluster headache type as other variables of interest, we found that the effect of subcutaneous octreotide 100μg was significantly superior to placebo (p < 0.01). Subcutaneous octreotide 100μg is effective in the acute treatment of cluster headache when compared with placebo. Nonvasconstrictor treatment of acute cluster headache is possible. Ann Neurol 2004

Electrocardiographic abnormalities in patients with cluster headache on verapamil therapy

Background: High dose verapamil is an increasingly common preventive treatment in cluster headache (CH). Side effects include atrioventricular block and bradycardia, although their incidence in this population is not clear. Method: This audit study assessed the incidence of arrhythmias on high dose verapamil in patients with cluster headache. Results: Of three hundred sixty-nine patients with cluster headache, 217 outpatients (175 men) received verapamil, starting at 240 mg daily and increasing by 80 mg every 2 weeks with a check electrocardiogram (EKG), until the CH was suppressed, side effects intervened, or to a maximum daily dose of 960 mg. One patient had 1,200 mg/day. Eighty-nine patients (41%) had no EKGs. One hundred eight had EKGs in the hospital notes, and a further 20 had EKGs done elsewhere. Twenty-one of 108 patients (19%) had arrhythmias. Thirteen (12%) had first-degree heart block (PR > 0.2 s), at 240 to 960 mg/day, with one requiring a permanent pacemaker. Four patients had junctional rhythm, and one had second-degree heart block. Four patients had right bundle branch block. There was bradycardia (HR < 60 bpm) in 39 patients (36%), but verapamil was stopped in only 4 patients. In eight patients the PR interval was lengthened, but not to >0.2 s. The incidence of arrhythmias on verapamil in this patient group is 19%, and bradycardia 36%. Conclusion: We therefore strongly recommend EKG monitoring in all patients with cluster headache on verapamil, to observe for the potential development of atrioventricular block and symptomatic bradycardia.

Trigeminal Autonomic Cephalalgias: Current and Future Treatments

The trigeminal autonomic cephalgias include cluster headache, paroxysmal hemicrania, and short‐lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT). The evidence for the current treatment options for each of these syndromes is considered, including oxygen, sumatriptan, and verapamil in cluster headache, indomethacin in paroxysmal hemicrania, and intravenous lidocaine and lamotrigine in SUNCT. Some treatments such as topiramate have an effect in all of these, as well as in migraine and other pain syndromes. The involvement of the hypothalamus in functional imaging studies implies that this may be a substrate for targeting treatment options in the future.

Post-traumatic chronic paroxysmal hemicrania (CPH) with aura

The authors describe a patient who developed chronic paroxysmal hemicrania (CPH) in close temporal relationship to a head injury. The subsequent attacks of CPH were associated with a typical migrainous sensory and motor aura. Administration of indomethacin 75 mg daily resulted in isolated occurrence of autonomic and aura symptoms in the absence of pain symptoms. The patient became completely asymptomatic on indomethacin 100 mg daily. Migrainous aura may be seen with trigeminal-autonomic headaches and may represent the expression of an aura-susceptibility gene rather than typical migraine headache biology.

Deep Brain Stimulation in Cluster Headache: Hypothalamus or Midbrain Tegmentum?

Functional and structural neuroimaging studies have provided pivotal insights into the pathophysiology of trigeminal autonomic cephalalgias (TACs), particularly cluster headache (CH). Functional imaging studies using positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) in TACs have reported activation of the posterior hypothalamus. A structural neuroimaging study using voxel-based morphometry in CH reported increased volume of the hypothalamic gray, although another larger study failed to reproduce this finding. These studies in CH prompted the use of stereotactic stimulation of the target point identified by functional and structural neuroimaging. The precise anatomical localization of the deep brain stimulation (DBS) target places it at the midbrain tegmentum rather than the posterior hypothalamus. A comparison of the PET and fMRI studies in TACs reveals that the diencephalic/mesencephalic activation is more posteroinferior in the PET studies, straddling the hypothalamus and midbrain tegmentum, whereas the activation is centered on the hypothalamus in the higher spatial resolution fMRI studies. To optimize the outcomes from DBS, it is likely that patients will need to be studied individually using functional imaging techniques that have high spatial and temporal resolution to enable targeting of the appropriate locus with stereotactic stimulation.

Quality of life in primary headache disorders: A review:

Background Health-related quality of life (HRQoL) is emerging as an important element of clinical research in primary headache disorders, allowing a measure of the impact of headache on patients’ well-being and daily life. A better understanding of this may contribute to improved resource allocations and treatment approaches. Objective The objective of this study is to review available data on HRQoL in primary headache disorders and identify any influencing factors. Methods Database searches including MEDLINE, PsycINFO and EMBASE were performed. Studies that investigated HRQoL in patients with primary headache disorders were included and reviewed. Trials that evaluated the efficacy of medications or interventions were excluded. Results A total of 80 articles were included in the review. Both physical and emotional/mental aspects of HRQoL were impaired across headache subtypes, although the extent varied depending on headache type. A number of factors influencing HRQoL were also identified. Conclusion This narrative review suggests that headache, particularly in its chronic form, has a great impact on HRQoL. Clinical practice should not solely focus on pain alleviation but rather adopt routine assessment of HRQoL. Furthermore, identification and management of associated psychological comorbidities, which can significantly influence HRQoL in headache sufferers, are essential for optimal clinical management.

Greater occipital nerve blocks in chronic cluster headache: a prospective open-label study

Greater occipital nerve blockade (GONB) has been shown to be effective in episodic cluster headache. However, its use in chronic cluster headache (CCH) is less certain. The study aims to prospectively assess the efficacy and consistency of response to GONB in a large series of CCH patients.

SUNCT, SUNA and trigeminal neuralgia: different disorders or variants of the same disorder?

PURPOSE OF REVIEW Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT), short-lasting unilateral neuralgiform headache attacks with autonomic symptoms (SUNA) and trigeminal neuralgia are considered different disorders, thus grouped in separate sections of the International Classification of Headache Disorders 3 beta. However, the clinical, radiological and therapeutic overlap between SUNCT, SUNA, and trigeminal neuralgia has challenged this traditional view. This review summarizes the available clinical and pathophysiological evidence on whether SUNCT, SUNA and trigeminal neuralgia should be considered separate entities or variants of the same disorder. RECENT FINDINGS Data on the clinical phenotype and effective management strategies in SUNCT and SUNA syndromes have shown striking similarities with trigeminal neuralgia. Moreover, studies exploring radiological findings supported the hypothesis of common aetiological and pathophysiological basis between SUNCT/SUNA and trigeminal neuralgia. However, a limitation of most studies is that they have included small samples of patients and therefore any conclusions need to be drawn cautiously. SUMMARY Despite being considered distinct conditions, emerging clinical and radiological evidence supports a broader nosological concept of SUNCT, SUNA, and trigeminal neuralgia. These conditions may constitute a continuum of the same disorder, rather than separate clinical entities. Further evidence is required to shed light on this nosological issue, given its potential impact on clinical practice and further research studies in this area.