Indomethacin-Responsive Headache Disorders.

OBJECTIVE: This article describes the clinical features and treatment of the indomethacin-responsive headache disorders paroxysmal hemicrania and hemicrania continua. LATEST DEVELOPMENTS: Both paroxysmal hemicrania and hemicrania continua are treated with indomethacin at the lowest clinically useful dose. It has recently become clear that some patients with either condition may respond to treatment with noninvasive vagus nerve stimulation, which can be both indomethacin sparing and, in some cases, headache controlling. Given the lifelong nature of both paroxysmal hemicrania and hemicrania continua, brain imaging with MRI is recommended when the conditions are identified, specifically including pituitary views. ESSENTIAL POINTS: Paroxysmal hemicrania and hemicrania continua are indomethacin-responsive headache disorders that offer a rewarding and unique opportunity to provide marked clinical improvement when recognized and treated appropriately. These disorders share the final common pathway of the trigeminal-autonomic reflex, with head pain and cranial autonomic features, and are differentiated pathophysiologically by the pattern of brain involvement, which can be seen using functional imaging. They have distinct differential diagnoses to which the clinician needs to remain alert.

One-year prevalence of cluster headache, hemicrania continua, paroxysmal hemicrania and SUNCT in Norway: a population-based nationwide registry study.

BACKGROUND: There is lack of population-based studies evaluating the prevalence of paroxysmal hemicrania, hemicrania continua and short-lasting unilateral neuralgiform headache attacks. OBJECTIVES: The aim of this study was to investigate the gender-specific 1-year prevalence of cluster headache, paroxysmal hemicrania, hemicrania continua, and short-lasting unilateral neuralgiform headache attacks. METHODS: A nationwide study was conducted from January 1 2022 and December 31 2022 by linking diagnostic codes from Norwegian Patient Registry and prescription of relevant drugs from Norwegian Prescription Database on an individual basis. The 1-year prevalence with 95% confidence intervals (CI) of cluster headache, paroxysmal hemicrania, hemicrania continua and short-lasting unilateral neuralgiform headache attacks are estimated based on the combination of diagnostic codes, prescription of drugs and corresponding reimbursement codes. RESULTS: Among 4,316,747 individuals aged ≥ 18 years, the 1-year prevalence per 100,000 was 14.6 (95% CI 13.5-15.8) for cluster headache, 2.2 (95% CI 1.8-2.7) for hemicrania continua, 1.4 (95% CI 1.0-1.8) for paroxysmal hemicrania, and 1.2 (95% CI 0.8-1.4) for short-lasting unilateral neuralgiform headache attacks. For all the trigeminal autonomic cephalalgies, cluster headache included, the prevalence was higher for women than men. CONCLUSIONS: In this nationwide register-based study, we found a 1-year prevalence per 100,100 of 14.6 for cluster headache, 2.2 for hemicranias continua, 1.4 for paroxysmal hemicranias, and 1.2 for short-lasting unilateral neuralgiform headache attacks. This is the first study reporting higher prevalence of cluster headache for women than men.

Epidemiology and clinical features of paroxysmal hemicrania: A systematic review and meta-analysis.

OBJECTIVE: To assess the prevalence or relative frequency of paroxysmal hemicrania and its clinical features in the adult general population and among adult patients evaluated for headache in tertiary care. BACKGROUND: Paroxysmal hemicrania is a rare trigeminal autonomic cephalalgia with characteristic attacks of headache, associated cranial autonomic symptoms and signs, and an absolute response to indomethacin. Its epidemiological burden remains unknown in both the adult general population and among adult patients evaluated for headache in a tertiary care setting. Moreover, the frequencies of the clinical features associated with paroxysmal hemicrania have not been well established. METHODS: A literature search of PubMed and Embase was conducted from January 1, 1988, to January 20, 2023. Eligible for inclusion were observational studies reporting the point prevalence or relative frequency of paroxysmal hemicrania or its clinical features in the adult general population or among adult patients evaluated for headache in tertiary care. Two independent investigators (M.J.H. and J.G.L.) performed the title, abstract, and full-text article screening. Each included study's risk of bias was critically appraised using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data. Estimates of prevalence or relative frequency were calculated using a random-effects meta-analysis. The between-study heterogeneity was assessed using the I2 statistic and further explored with meta-regression. This study was pre-registered on PROSPERO (identifier: CRD42023391127). RESULTS: A total of 17 clinic-based studies and one population-based study met the eligibility criteria. Importantly, an overall high risk of bias was observed across the eligible studies. The relative frequency of paroxysmal hemicrania was estimated to be 0.3% (95% CI, 0.2%-0.5%) among adult patients evaluated for headache in tertiary care with considerable heterogeneity (I2 = 76.4%). No cases with paroxysmal hemicrania were identified among 1,838 participants in a population-based sample. Moreover, the most prevalent cranial autonomic symptoms were lacrimation (77.3% [95% Cl, 62.7%-87.3%]), conjunctival injection (75.0% [95% Cl, 60.3%-85.6%]), and nasal congestion (47.7% [95% Cl, 33.6%-62.3%]). CONCLUSIONS: Our findings suggest that paroxysmal hemicrania is a rare disorder among adults evaluated for headache in tertiary care, while its prevalence in the general population remains unknown. Further studies focusing on the clinical features of paroxysmal hemicrania are warranted.

Paroxysmal hemicrania and hemicrania continua: Review on pathophysiology, clinical features and treatment.

BACKGROUND: Paroxysmal hemicrania and hemicrania continua are indometacin-sensitive trigeminal autonomic cephalalgias, a terminology which reflects the predominant distribution of the pain, observable cranial autonomic features and shared pathophysiology. Understanding the latter is limited, both by low prevalence and the intricacies of studying brain function, requiring multimodal techniques to glean insights into such disorders. Similarly obscure is the curious response to indometacin. This review will address what is currently known about pathophysiology, the rationale for the current classification and, features which may confound the diagnosis, such as lack of cranial autonomic symptoms and those which are typically associated with migraine such as nausea, photophobia, phonophobia and aura. Despite these characteristics, a dramatic response to indometacin, which is not seen in migraine nor the other trigeminal autonomic cephalalgias , provides the hallmark of the diagnosis. The main clinical differential for paroxysmal hemicrania is based on temporal pattern and lies between cluster headache and short-lasting-neuralgiform headache attacks with tearing or additional cranial autonomic symptoms. For hemicrania continua it is more challenging as the main differential for which the disorder is often treated is migraine. A prior episodic pattern, often days at a time, and the tendency to exacerbation with analgesics will further deflect from the diagnosis. The relevance of this is that there is little overlap in therapeutics between paroxysmal hemicrania and hemicrania continua and other headache disorders and there are limited effective alternatives to indometacin. The most effective are other non-steroidal anti-inflammatory drugs including the newer COX-II inhibitors. Even though early reports suggest that a higher indometacin dose-requirement may herald a secondary precipitating pathology, this does not seem to be the case, with syndrome and response to treatment being similar with the primary disorder. In this context imaging of new onset paroxysmal hemicrania or hemicrania continua and implication of the results will be discussed as will alternative treatment options.

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.

Paroxysmal hemicrania in children and adolescents: A systematic review.

OBJECTIVE: We aimed to report the accessible demographic, clinical, and radiological characteristics of reported pediatric paroxysmal hemicrania (PH). INTRODUCTION: It has been a while since PH in a child was first described. However, it is still unknown whether children's PH follows the same patterns as adults. METHODS: This study followed the latest version of PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). PubMed, Web of Science, and Scopus were searched systematically without time limitation. We included all English-language, peer-reviewed articles, including observational or interventional studies reporting PH cases in children or adolescents based on the International Classification of Headache Disorders (ICHD) criteria. Data extracted included PH class; sex; age; age of onset; frequency, duration, site, severity, and quality of pains; triggers; and autonomic and migrainous symptoms, as well as a sense of restlessness/agitation, response to treatment, laboratory investigations, imaging, comorbidity, and family history. For quality assessment, two independent reviewers (MB and VM) assessed the methodological quality of the included studies through the Joanna Briggs Institute's critical appraisal checklist. RESULTS: A total of 182 records were identified and reduced to 116 after removing duplicates. After screening, 22 articles met the inclusion criteria. Overall, the studies represented 35 children or adolescents with PH. We found a boy-to-girl ratio of 1.125:1. Onset occurred at a broad range of 1 to 14 years old. The mean age of onset among reported cases in children and adolescents was 6.5 years, while the mean age of diagnosis was 8.2 years. [Correction added on 22 August 2022, after first online publication: In the preceding sentence, 6.3 and 7.9 years were changed to 6.5 and 8.2 years, respectively.] The attacks' frequency and duration were greatly varied. Left-sided pain occurred twice as often as right-sided pain. The characteristics of the pain were usually severe in intensity. In nearly all of the cases, it was accompanied by ipsilateral cranial autonomic features. While most attacks were spontaneous, there were some common triggers. The physical examination, electroencephalogram, and brain magnetic resonance imaging had normal findings. Almost all patients benefited from indomethacin and showed complete responses to treatment, while some needed combination treatment of indomethacin with other medications. CONCLUSION: Although pediatric-onset PH has similar features to adult-onset PH, there are some challenges with ICHD criteria for younger children that limit the ability to confidently assign a diagnosis. Moreover, owing to concomitant migrainous features, PH may be confused with migraine in children and adolescents.

A Combination of Indomethacin Farnesyl and Amitriptyline Is Effective for Continuous Interictal Pain with Probable Chronic Paroxysmal Hemicrania.

A 26-year-old woman with a history of migraine reported right-sided, severe stabbing orbital pain with cranial autonomic symptoms (CASs) for approximately 2 years. The attack duration was approximately 30 minutes, with a frequency of twice per day. Taking loxoprofen was ineffective. Six months earlier, moderate pressing continuous interictal pain without CASs had developed. Indomethacin farnesyl completely resolved the attacks but had no effect on the interictal pain. The patient was diagnosed with probable chronic paroxysmal hemicrania in accordance with the International Classification of Headache Disorders (ICHD-3) (third version). Continuous interictal pain gradually disappeared with a combination of indomethacin farnesyl and amitriptyline.

Paroxysmal Hemicrania: An Update.

Paroxysmal Hemicrania (PH) is classified under trigeminal autonomic cephalalgia (TAC) as per the International Classification of Headache Disorders (ICHD). Since the first description by 0ttar Sjaastad and Inge Dale in 1974, PH has been reported by many authors. A greater understanding of PH phenotype and pathophysiology has resulted in the evolution of its diagnostic criteria, and management. We tabulated major case series of PH to describe the epidemiology, clinical features and recent updates of PH. PH is a rare headache characterized by daily, multiple paroxysms of unilateral, short-lasting (mean duration <20 minutes), side-locked headache in the distribution of ophthalmic division of trigeminal nerve with associated profound cranial autonomic symptoms. Recent ICHD classification added "restlessness" to the criteria for PH. Pain should completely respond to indomethacin to fulfil the diagnostic criteria of PH. PH should be differentiated from cluster headache, SUNCT/SUNA, and other short-lasting side-locked headaches. Trigeminal afferents possibly produce pain in PH and trigeminal-autonomic reflex explains the occurrence of autonomic features. Recently, a "permissive" central role of the hypothalamus is unveiled based on functional imaging studies. Other Cox-2 inhibitors, topiramate, calcium-channel blockers, epicranial nerve blocks have been shown to improve headache in some patients of PH who cannot tolerate indomethacin. Hypothalamic deep brain stimulation has been used in treatment-refractory cases.

Paroxysmal hemicrania masquerading as a stroke in an elderly gentleman: case report.

BACKGROUND: Paroxysmal hemicrania has not been associated with ipsilateral weakness, loss of sensation and Horner's syndrome. This report is the first of its kind documented in literature. CASE PRESENTATION: This was an elderly, sixty-five-year-old Chinese male who presented with a headache fulfilling criteria of paroxysmal hemicrania and was found to have signs of ipsilateral conjunctival injection, Horner's syndrome, weakness and loss of sensation; with resolution of the patient's physical signs after relief of the headache. Brain magnetic resonance imaging did not show any strokes or other headache mimics. The patient had a marked response to indomethacin and a decrease of headache intensity and frequency with indomethacin prophylaxis. CONCLUSIONS: Paroxysmal hemicrania has joined the list of stroke chameleons and that it would be one of the differentials in a patient with hemiplegia, hemisensory loss, autonomic signs and severe headache. It suggests that paroxysmal hemicrania in the elderly present atypically.

Headache in the Older Population: Causes, Diagnoses, and Treatments.

PURPOSE OF REVIEW: Primary headaches are less common and differ in presentation in older versus younger individuals. Secondary headaches become more common among older patients. RECENT FINDINGS: Diagnosis and management of headaches in those > 65 years are discussed. Migraine and tension-type headaches are rarely new onset in this age group and should be a diagnosis of exclusion. In older individuals, migraine is more likely to be bilateral with less sensory sensitivities. Migraine aura may present without headache; careful assessment is needed to exclude stroke. Other primary headaches discussed include cough, hypnic, and other headaches. Secondary causes discussed include giant cell arteritis, trigeminal post-herpetic neuropathy, sleep apnea, cardiac cephalgia, cervicogenic pain, vascular etiologies, medications, and burning-mouth syndrome. In older individuals, primary headaches are diagnoses of exclusion, and treatment is affected by comorbidities and polypharmacy. Secondary headaches are a major consideration requiring appropriate workup. Many treatments can safely be offered regardless of age.

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.

Therapeutical approaches to paroxysmal hemicrania, hemicrania continua and short lasting unilateral neuralgiform headache attacks: a critical appraisal.

BACKGROUND: Hemicrania continua (HC), paroxysmal hemicrania (PH) and short lasting neuralgiform headache attacks (SUNCT and SUNA) are rare syndromes with a difficult therapeutic approach. The aim of this review is to summarize all articles dealing with treatments for HC, PH, SUNCT and SUNA, comparing them in terms of effectiveness and safety. METHODS: A survey was performed using the pubmed database for documents published from the 1st January 1989 onwards. All types of articles were considered, those ones dealing with symptomatic cases and non-English written ones were excluded. RESULTS: Indomethacin is the best treatment both for HC and PH. For the acute treatment of HC, piroxicam and celecoxib have shown good results, whilst for the prolonged treatment celecoxib, topiramate and gabapentin are good options besides indomethacin. For PH the best drug besides indomethacin is piroxicam, both for acute and prolonged treatment. For SUNCT and SUNA the most effective treatments are intravenous or subcutaneous lidocaine for the acute treatment of active phases and lamotrigine for the their prevention. Other effective therapeutic options are intravenous steroids for acute treatment and topiramate for prolonged treatment. Non-pharmacological techniques have shown good results in SUNCT and SUNA but, since they have been tried on a small number of patients, the reliability of their efficacy is poor and their safety profile mostly unknown. CONCLUSIONS: Besides a great number of treatments tried, HC, PH, SUNCT and SUNA management remains difficult, according with their unknown pathogenesis and their rarity, which strongly limits the studies upon these conditions. Further studies are needed to better define the treatment of choice for these conditions.

The Rare Painful Phenomena - Chronic Paroxysmal Hemicrania-tic Syndrome as a Clinically Isolated Syndrome of the Central Nervous System.

The association of paroxysmal hemicrania with trigeminal neuralgia (TN) has been described and called paroxysmal hemicrania-tic syndrome (PH-tic). We report the case of a patient diagnosed as having chronic PH-tic (CPH-tic) syndrome as a clinically isolated syndrome of the central nervous system (CNS) (CIS).A forty year old woman was admitted to our hospital suffering from right facial pain for the last 2 years. The attacks were paroxysmal, neuralgiform, consisting of throb-like sensations, which developed spontaneously or were triggered by different stimuli in right facial (maxilar and mandibular) areas. Parallel with those, she felt a throbbing orbital and frontal pain with homolateral autonomic symptoms such as conjunctival injection, lacrimation, and the feeling that the ear on the same side was full. This pain lasted most often between 15 and 20 minutes. Beyond hemifacial hypoesthesia in the region of right maxilar and mandibular nerve, the other neurological finding was normal. Magnetic resonance imaging (MRI) study showed a T2-weighted multiple hyperintense paraventricular lesion and hyperintense lesion in the right trigeminal main sensory nucleus and root inlet, all of them being hypointense on T1-weighted image. All of these lesions were hypointense in gadolinium-enhanced T1-weighted images. Neurophysiological studies of trigeminal nerve (somatosensory evoked potentials and blink reflex) correlated with MRI described lesions. The patient's pain bouts were improved immediately after treatment with indomethacin, and were completely relieved with lamotrigine for a longer period. According to the actual McDonald's criteria, clinical state was defined as CIS which was clinically presented by CPH-tic syndrome.Even though it is a clinical rarity and its etiology is usually idiopathic, CPH-tic syndrome can also be symptomatic. When dealing with symptomatic cases, like the one described here, when causal therapy is not possible due to the nature of the primary pathological process, a therapeutic approach, although symptomatic, can be fully effective in controlling this painful syndrome. The case report could be a contribution to the pathophysiological and clinical understanding of the association of CPH and TN.Key words: Paroxysmal hemicrania, trigeminal neuralgia, clinically isolated syndrome.

Side-locked headaches: an algorithm-based approach.

The differential diagnosis of strictly unilateral hemicranial pain includes a large number of primary and secondary headaches and cranial neuropathies. It may arise from both intracranial and extracranial structures such as cranium, neck, vessels, eyes, ears, nose, sinuses, teeth, mouth, and the other facial or cervical structure. Available data suggest that about two-third patients with side-locked headache visiting neurology or headache clinics have primary headaches. Other one-third will have either secondary headaches or neuralgias. Many of these hemicranial pain syndromes have overlapping presentations. Primary headache disorders may spread to involve the face and / or neck. Even various intracranial and extracranial pathologies may have similar overlapping presentations. Patients may present to a variety of clinicians, including headache experts, dentists, otolaryngologists, ophthalmologist, psychiatrists, and physiotherapists. Unfortunately, there is not uniform approach for such patients and diagnostic ambiguity is frequently encountered in clinical practice.Herein, we review the differential diagnoses of side-locked headaches and provide an algorithm based approach for patients presenting with side-locked headaches. Side-locked headache is itself a red flag. So, the first priority should be to rule out secondary headaches. A comprehensive history and thorough examinations will help one to formulate an algorithm to rule out or confirm secondary side-locked headaches. The diagnoses of most secondary side-locked headaches are largely investigations dependent. Therefore, each suspected secondary headache should be subjected for appropriate investigations or referral. The diagnostic approach of primary side-locked headache starts once one rule out all the possible secondary headaches. We have discussed an algorithmic approach for both secondary and primary side-locked headaches.

Putative pathophysiological mechanisms in recurrent hemicrania from aortic dissection: a case report.

BACKGROUND: Transient or permanent neurological symptoms occur in 17-40% of patients with aortic dissection. They can distract from or even mask the underlying life-threatening condition. CASE PRESENTATION: We present the case of a young Caucasian man who consulted for recurrent episodes of stereotyped right-sided sudden-onset severe headache. Upon questioning, he also reported a dull chest pain. Clinical examination and brain magnetic resonance imaging were unremarkable. The concomitant presence of chest pain made us consider aortic dissection. Contrast-enhanced cervico-thoraco-abdominal computerized tomography revealed type A aortic dissection. The patient underwent surgical replacement of the ascending aorta and reported no further episode of headache thereafter. Differential diagnosis of headache in this case includes paroxysmal hemicrania, cluster headache, migraine, trigeminal neuralgia and short lasting unilateral neuralgiform headache with conjunctival injection and tearing. Failure to match diagnostic criteria for any of these primary headache disorders and the resolution of pain episodes following surgery led us to postulate that these new-onset hemicrania episodes were symptomatic of aortic dissection. We hypothesize that aortic wall ischemia could have activated the trigeminovascular system and thereby caused hemicranial pain. Such an effect might be mediated by two different pathways that can be referred to as anatomical and humoral. The humoral hypothesis would posit that ischemia results in synthesis of pro-inflammatory mediators released from the aortic wall into the blood stream, such that they reach the central nervous system and directly stimulate specific receptors. The anatomical hypothesis would imply that pain signals generated by nociceptors in the aortic wall are transferred to the trigeminal ganglion via the cardiac plexus, the first cervical ganglion and the internal carotid nerve such that pain perception is referred to related cranio-cervical dermatomes. CONCLUSION: In cases of isolated headache that does not match key diagnostic criteria for a primary headache entity; a thorough review of systems should be performed to look for symptoms that may indicate symptomatic headache from potentially life-threatening conditions. Neurologists should consider aortic dissection in patients presenting with acute headache and chest pain. Further clinical or experimental studies are required to refute or validate the pathophysiological hypothesis discussed here.

Do trigeminal autonomic cephalalgias represent primary diagnoses or points on a continuum?

The question of whether the trigeminal autonomic cephalalgias (TACs) represent primary diagnoses or points on a continuum has been debatable for a number of years. Patients with TACs may present with similar clinical characteristics, and occasionally, TACS respond to similar treatments. Prima facie, these disorders may seem to be intimately related. However, due to the current evidence, it would be challenging to accurately conclude whether they represent different primary headache diagnoses or the same primary headache disorder represented by different points on the same continuum. Ultimately, the TACs may utilize similar pathways and activate nociceptive responses that result in similar clinical phenotypes but "original and initiating" etiology may differ, and these disorders may not be points on the same continuum. This paper seeks to provide a brief comparison of TACs via diagnostic criteria, secondary causes, brief overview of pathophysiology, and the use of some key treatments and their mechanism of actions to illustrate the TAC similarities and differences.