Hemicrania Continua Evolving from Episodic Paroxysmal Hemicrania

Hemicrania Continua

Hemicrania continua (HC) is an indomethacin responsive primary chronic headache disorder which is currently classified as a subtype of trigeminal autonomic cephalalgias (TACs). It is not very uncommon. There are >1000 cases of HC in the literature, and it constitutes 1.7% of total headache in the clinic settings. Misdiagnosis for HC is very common at all clinical settings. A diagnosis of HC is missed even by neurologists and headache specialists. It is characterized by a continuous strictly unilateral headache with superimposed exacerbations. Just like other TACs, exacerbations are associated with cranial autonomic symptoms and restlessness. A large number of patients may have migrainous features (nausea, vomiting, photophobia, and phonophobia) during exacerbations phase. The “key” feature of HC is persistent featureless background headaches. However, patients and physicians may focus only on the exacerbation part. As durations, frequency and associated symptoms of exacerbations are highly variables; it may mimic a large number of primary and secondary headache disorders. Migraine and cluster headache are two most common misdiagnosed conditions. Another specific feature of HC is remarkable repose to indomethacin. A “complete” response to indomethacin is as “sine qua non” for HC. However, a few other medications may also be effective in a subset of HC patients. Various surgical procedures have been tried with mixed results in patients who were intolerant to indomethacin or other drugs.

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.

Electronic supplementary material

The online version of this article (doi:10.1186/s10194-017-0777-3) contains supplementary material, which is available to authorized users.

Hemicrania continua: clinical review, diagnosis and management

Hemicrania continua (HC) is an indomethacin-responsive primary headache disorder which is currently classified under the heading of trigeminal autonomic cephalalgias (TACs). It is a highly misdiagnosed and underreported primary headache. The pooled mean delay of diagnosis of HC is 8.0 ± 7.2 years. It is not rare. We noted more than 1000 cases in the literature. It represents 1.7% of total headache patients attending headache or neurology clinic. Just like other TACs, it is characterized by strictly unilateral pain in the trigeminal distribution, cranial autonomic features in the same area and agitation during exacerbations/attacks. It is different from other TACs in one aspect. While all other TACs are episodic, HC patients have continuous headaches with superimposed severe exacerbations. The central feature of HC is continuous background headache. However, the patients may be worried only for superimposed exacerbations. Focusing only on exacerbations and ignoring continuous background headache are the most important factors for the misdiagnosis of HC. A large number of patients may have migrainous features during exacerbation phase. Up to 70% patients may fulfill the diagnostic criteria for migraine during exacerbations. Besides migraine, its exacerbations can mimic a large number of other primary and secondary headaches. The other specific feature of HC is a remarkable response to indomethacin. However, a large number of patients develop side effects because of the long-term use of indomethacin. A few other medications may also be effective in a subset of patients with HC. Various surgical interventions have been suggested for patients who are intolerant to indomethacin. Several aspects of HC are still not defined. There is a great heterogeneity in types of patients or articles on the HC in the literature. Diagnostic criteria have been modified several times over the years. The current diagnostic criteria are too restrictive in some aspects. We suggest a more accommodating type of criteria for the appendix of International Classification of Headache Disorder (ICHD).

Indomethacin Responsive Headaches: Exhaustive Systematic Review with Pooled Analysis and Critical Appraisal of 81 Published Clinical Studies

OBJECTIVES

The relationship between indomethacin (IMC) and headache treatment has long intrigued clinicians and clinical researchers in Headache Medicine. Why is it efficacious in many types of headache disorders when other medications are not, and what is the mechanism behind its efficacy? IMC and headache related topics that have been explored in detail in the literature include IMC-responsive headache disorders ("traditional"), pharmacology of IMC, symptomatic headaches responsive to IMC, "novel" headache conditions that respond, cluster headache and IMC, IMC provoking headache, the issue about" absolute" and "non-absolute" effect of IMC on headache disorders, and the morphing trigeminal autonomic cephalalgias (TACs).

DATA SOURCE

A PubMed/MEDLINE search was used for Clinical Studies Categories and Systematic Reviews on the PubMed Clinical Queries. The search details were "indomethacin" AND "headache" spanning all previous years until February 1, 2015. Methods were in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

REVIEW METHODS

Articles were excluded if IMC had not been used to treat headache disorders in adults, if the article concerned IMC-responsive headaches but made no reference to the use of IMC, and articles not addressing the above mentioned topics.

RESULTS AND CONCLUSIONS

The "velocity" of publications on IMC and headache seems to be decreasing, particularly on the use of IMC for the treatment of TACs. The science behind the understanding of the putative mechanisms of IMC's action on headache has moved forward, but the answer to why it works better than other nonsteroidal anti-inflammatory drugs has been elusive. There are case reports of other rare headache disorders that may be responsive to IMC. The dosages of IMC used as a tool for detecting IMC responsive disorders vary according to different centers of investigation. In many circumstances, headache disorders similar to "primary" IMC-responsive disorders are actually symptomatic disorders. Cluster headache as an IMC-resistant headache disorder may not be as absolute as once thought. Sometimes, IMC has been found to provoke headache; differentiating IMC-provoked headache from IMC-resistant headache can make headache diagnosis and management difficult. As for the "absolute" responsiveness of IMC, it is possible that using higher dosages leads to higher sensitivity, probably at the expense of decreased specificity. There are many reports about the occurrence of two or more IMC-responsive disorders (latu sensu) in the same patient, which may be coincidental.

Hemicrania continua changed to chronic paroxysmal hemicrania after treatment with cyclooxygenase-2 inhibitor

Remission of hemicrania continua (HC) and transformation from HC to chronic paroxysmal hemicrania (CPH) are unusual. We report a patient with left-sided HC who, after a period of remission, presented as CPH. The continuous HC headache disappeared completely after initiating treatment with cyclooxygenase (COX)-2 inhibitor, but reappeared on the same side after 14 months remission with paroxysmal, frequent, intense and short-lasting headache attacks accompanied by ipsilateral cranial autonomic symptoms. This happened shortly after the treatment was discontinued because of withdrawal of the COX-2 inhibitor from the market. The response to indomethacin was prompt, and the patient became completely free from her paroxysmal headache with a dose of 50 mg 2 times daily. This case questions a possible modification effect on the course of HC by use of COX-2 inhibitor, as well as further supporting that some aspects of the pathophysiology of HC may resemble those of CPH, and may argue for common biological mechanisms in HC and CPH.

Trigemino-autonomic headache related to Gasperini syndrome

We report the association of ipsilateral trigemino-autonomic headache to a case of right-sided nuclear facial and abducens palsy (Gasperini syndrome), ipsilateral hypacusis and right hemiataxia, caused by the occlusion of the right anterior inferior cerebellar artery. Short-lasting attacks of mild to moderate ipsilateral fronto-periorbital head pain, accompanied by lacrimation and mild conjunctival injection during more severe attacks, were present from the onset of symptoms, with a gradual worsening over the next few months and remitting during naproxen therapy. Magnetic resonance imaging showed an infarct in the right cerebellar peduncle, extending toward the pontine tegmentum, also involving the ipsilateral spinal trigeminal nucleus and tract and the trigeminal entry zone. Gasperini syndrome may be accompanied by ipsilateral trigemino-autonomic head pain.

Different forms of trigeminal autonomic cephalalgias in the same patient: description of a case

The trigeminal autonomic cephalalgias (TACs), including cluster headache, paroxysmal hemicrania and SUNCT, are characterized by the cardinal combination of short-lasting unilateral pain and autonomic phenomena affecting the head. Hemicrania continua (HC) shares many clinical characteristics with TACs, including unilateral pain and ipsilateral autonomic features. Nevertheless, HC is separately classified in the revised International Classification of Headache Disorders (ICHD-II). Here, we describe the case of a 45-year-old man presenting an unusual concurrence of different forms of primary headaches associated with autonomic signs, including subsequently ipsilateral cluster headache, SUNCT and HC. This report supports the theory that common mechanisms could be involved in pathophysiology of different primary headache syndromes.

Hemicrania Continua: Who Responds to Indomethacin?

Hemicrania continua (HC) is a primary headache disorder characterized by a continuous, moderate to severe, unilateral headache and defined by its absolute responsiveness to indomethacin. However, some patients with the clinical phenotype of HC do not respond to indomethacin. We reviewed the records of 192 patients with the putative diagnosis of HC and divided them into groups based on their headaches' response to indomethacin. They were compared for age, gender, presence or absence of specific autonomic symptoms, medication overuse, rapidity of headache onset, and whether or not the headaches met criteria for migraine when severe. Forty-three patients had an absolute response and 122 patients did not respond to adequate doses of indomethacin. The two groups did not differ significantly in terms of age, sex, presence of rapid-onset headache, or medication overuse. Autonomic symptoms, based on a questionnaire, did not predict response. Eighteen patients could not complete a trial of indomethacin due to adverse events. Nine patients could not be included in the HC group despite improvement with indomethacin: one patient probably had primary cough headache, another paroxysmal hemicrania; three patients improved but it was uncertain if they were absolutely pain free, and four patients dramatically improved but still had a baseline headache. We found no statistically significant differences between patients who did and did not respond to indomethacin. All patients with continuous, unilateral headache should receive an adequate trial of indomethacin. Most patients with unilateral headache suggestive of HC did not respond to indomethacin.

Trigeminal autonomic cephalalgias. Part 2: Paroxysmal hemicrania

Paroxysmal hemicrania (PH) is characterized by severe, strictly unilateral pain attacks lasting 2 to 30 minutes localized to orbital, supraorbital, and temporal areas accompanied by ipsilateral autonomic features. It represents 1 of 3 primary headaches classified as trigeminal autonomic cephalalgias. Although PH is rare, patients may present to dental offices seeking relief for their pain. It is important for oral health care providers to recognize PH and render an accurate diagnosis. This will avoid the pitfall of implementing unnecessary and inappropriate traditional dental treatments in hopes of alleviating this neurovascular pain. This is part 2 of a review on trigeminal autonomic cephalalgias and focuses on PH. Aspects of PH including epidemiology, genetics, pathophysiology, clinical presentation, classification and variants, diagnosis, medical management, and dental considerations are discussed.