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 » Epidemiology
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REVIEW ARTICLE
Year : 2021  |  Volume : 69  |  Issue : 7  |  Page : 160-167

Hemicrania Continua: An Update


Department of Neurology, Smt. B. K. Shah Medical Institute and Research Centre, Sumandeep Vidyapeeth, Piparia, Waghodia, Vadodara, Gujarat, India

Date of Submission12-Oct-2020
Date of Decision16-Jan-2021
Date of Acceptance13-Feb-2021
Date of Web Publication14-May-2021

Correspondence Address:
Dr. Sanjay Prakash
Department of Neurology, Smt. B. K. Shah Medical Institute and Research Centre Medical College, Piperia, Waghodia, Vadodara - 391 760, Gujarat
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0028-3886.315976

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 » Abstract 


Background: Hemicrania continua (HC) is not uncommon in clinical practice, and several large case series have been published in the recent past.
Objectives: This review provides an overview of the recent advancement in different aspects of HC.
Methods: We reviewed the articles published on HC in the last 2 decades.
Results: HC constitutes 1.7% of patients with headache in the clinics. It presents with unilateral continuous background pain with periodic exacerbations, usually accompanied by cranial autonomic features and restlessness. The continuous background headache is the most consistent and central feature of HC. Although the duration of exacerbations varies from a few seconds to a few weeks, the frequency ranges from >20 attacks/day to one attack in several months. The background pain is mild to moderate in intensity and does not hamper routine activity. Patients and physicians frequently ignore the basal pain, and a case of HC is misdiagnosed as other headaches, depending on the pattern of exacerbations. The exacerbation mimics several primary headaches and neuralgias. There are about 75 cases of secondary HC, due to 29 different pathologies. Although an absolute response to indomethacin is part of the diagnostic criteria, a subset of patients may respond to several other drugs. Headache reappears immediately on skipping a single dose of effective drug. Several surgical procedures have been tried in patients who are intolerant to indomethacin.
Conclusion: Misdiagnosis of HC is common. Continuous background pain and response to indomethacin are two essential features for the diagnosis of HC.


Keywords: Hemicrania continua, indomethacin, trigeminal autonomic cephalalgias
Key Messages: Hemicrania continua is an underdiagnosed indomethacin responsive primary headache disorder that mimics several primary and secondary headaches. There is a need to increase awareness about HC among physicians.


How to cite this article:
Prakash S, Rawat KS. Hemicrania Continua: An Update. Neurol India 2021;69, Suppl S1:160-7

How to cite this URL:
Prakash S, Rawat KS. Hemicrania Continua: An Update. Neurol India [serial online] 2021 [cited 2021 Jun 17];69, Suppl S1:160-7. Available from: https://www.neurologyindia.com/text.asp?2021/69/7/160/315976




Hemicrania continua (HC) is a primary headache disorder, which is classified by the International Classification of Headache Disorder, third edition (ICHD-3), under the heading of trigeminal autonomic cephalalgias (TACs), along with cluster headache (CH), paroxysmal hemicrania (PH), short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT), and short-lasting unilateral neuralgiform headache with autonomic symptoms (SUNA).[1],[2]

The earliest published account of HC is attributed to a 1981 case series by Medina and Diamond. They described them under the heading of “cluster headache variant.”[3] Sjaastad and Spierings coined the word “hemicrania continua” in 1984.[4]


 » Epidemiology Top


Prevalence

The incidence and prevalence of HC are not known. It was considered to be a very rare syndrome till Peres et al. reported a case series of 34 patients in 2001. Peres and colleagues titled the article “Hemicrania continua is not that rare.”[5] There is just one study describing the prevalence of HC in the general population. The Vågå study noted 18 patients (1%) with clinical features resembling HC among 1,838 parishioners in the age group of 18–65 years.[6] Indomethacin was not given to these patients, and the diagnosis remains in “the probable HC” category. HC was a relatively new headache when the Vågå study was conducted in 1995, and several aspects of HC were not well described in the literature. Therefore, the Vågå study may not reflect the true prevalence of HC.

Most of the data on HC have been derived from clinic-based studies. The prevalence of HC varies between 1.3 to 2.3% (mean = 1.7%) of total patients with headache attending neurology or headache clinics.[2] HC was the third most common cause in a series of 307 patients with side-locked headaches.[7] Wei and colleagues assessed the primary headache disorders in a multidisciplinary orofacial pain clinic. HC was the second most common primary headache disorder.[8] Thus, HC is not an uncommon headache disorder seen in headache clinics.

HC is probably the most misdiagnosed primary headache.[2] Patients reported by Rossi et al. (25 patients), Prakash et al. (31), Cortijo et al. (22), and de Moura et al. (10) did not get the correct diagnosis before visiting their respective headache clinics.[9],[10],[11],[12] About 80% of patients in Rossi et al.'s study and 60% of patients in Prakash et al. series had already visited the neurologists without getting a correct diagnosis.[9],[10] Approximately 28% of patients in Rossi et al. study had already visited headache experts.[10] In a pooled analysis, the mean delay of diagnosis for HC was 8 ± 7.2 years.[2]

Age

HC typically begins in the fourth or fifth decade of life. The mean age of onset varied between 28–53 years in different studies (pooled mean age = 40.2 years).[2] However, no age is immune and it can begin at any age. HC have been reported in the literature for several childhood-onset cases (in patients as young as 5 years) and in the seventh and eighth decades of life.[5]

Gender

Similar to migraine and tension-type headache, HC is more common in women. In an earlier review, the male-to-female ratio was 1:5.[13] However, the female preponderance has reduced over the years, and the male: female ratio was 1:1.8 in a recent review of the literature.[2]

Family history and genetic predisposition

Pareja and colleagues reported a 31-year-old man with episodic HC whose sister had a history of HC.[14] Weatherall and Bahra reported a mother and daughter having HC at the same time. Both responded to indomethacin.[15]


 » Clinical Features Top


HC is characterized by a strictly unilateral, mild-to-moderate continuous headache with superimposed exacerbations of severe intensity in the trigeminal distribution. The exacerbation is associated with ipsilateral cranial autonomic symptoms (CAS), agitation or restlessness, and migrainous features. By definition, a case of HC should show complete response to indomethacin.[1]

Laterality of pain

Patients with HC have a strictly unilateral headache, with a slight preponderance for the right side (53%). About 2% of patients with HC may have side-shifting pain. A few cases of bilateral HC have also been reported in the literature.[2]

Site of pain

The headaches in TACs classically present in the ophthalmic division of the trigeminal nerve and the ICHD-3 acknowledges the presence of unilateral headache in the orbital, supraorbital, and/or temporal areas in all TACs except HC. ICHD-3 does not describe the sites of pain in HC and simply mentions “unilateral headache.”[1] However, several large case series suggest that the pain in HC is predominantly in the orbital, supraorbital, and/or temporal area.[2],[16] Similarly, like other TACs, the pain in HC may spread to involve other divisions of the trigeminal nerve, and may be noted in the occiput, neck, shoulder, upper limb, maxilla, mandible, periauricular area, and oral cavity (including teeth and throat).[2],[10],[16],[17] A substantial number of patients may have predominant or isolated symptoms in an atypical location, and it may create diagnostic confusion.[18] In one study, estimating the prevalence of facial pain in different primary headaches, about 21% of patients with HC had facial pain.[19] Hryvenko et al. noted six patients with HC in a tertiary orofacial pain clinic. Four out of six patients had facial pain. One patient had a toothache and another had jaw pain.[20] The identification of such atypical patients is very important as they respond dramatically to indomethacin, and patients can be saved from various erroneous treatments, including invasive surgeries.

Pain characteristics and pattern

The headache in HC has two components: 1) continuous background pain and 2) superimposed severe exacerbations [Figure 1]a. Continuous background headache is the most consistent and central feature of HC.[2] Missing the history of background pain is probably the most common reason for a delayed or wrong diagnosis. The background pain is perceived as dull and pressure like a tension-type headache. It is typically mild to moderate in severity, 3.3 to 5.2 on the visual analog scale (VAS), and does not hamper any routine activities.[2] In Peres et al.'s study on 34 patients, 82% of patients had no or very mild physical disability due to background pain.[5] Patients considered this background headache as “normal” and they may not volunteer about the background pain.[10]
Figure 1: Diagrammatic representation of hemicrania continua and its differential diagnosis. (a) Components of pain in hemicrania continua. (b) Differential diagnosis – if you focus on exacerbations only and not consider background pain. (c) Differential diagnosis of HC – if you focus on background pain and ignore exacerbations

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The exacerbations are highly variable in terms of intensity, character, duration, and frequency. The character of exacerbation is typically throbbing or stabbing (jabs and jolts) or a combination of both.[2] The VAS for severe exacerbations ranges from 5 to 10 (mean pooled VAS score = 9). Approximately 40% of patients graded the superimposed pain at 10 of VAS.[2] In Cittadini and Goadsby's observations, about 50% of patients felt that their pains were the most painful conditions they had ever experienced, compared with labor pain, a broken bone, toothache, and burned hands. In this regard, the pain of exacerbations matches the pain of CH and PH.[7] Like CH and PH, the patients with HC may have suicidal ideation during exacerbations.[2]

ICHD-3 is silent regarding the frequency and duration of superimposed attacks.[1] The literature review suggests a variable duration of exacerbations, which can vary from a few seconds to a few weeks. Similarly, the frequency of superimposed attacks is also highly variable and varies from >20 attacks/day to one attack in 4-month duration.[2]

None of the studies showed any circadian periodicity. Exacerbations can occur at any time, including at night. About 53% of patients in Cittadini and Goadsby's series had exacerbations during the night time. Unlike CH, only a few case reports of HC have mentioned the worsening of headache attacks (or relapses in remitting subtypes) during particular seasons. Remitting HC with seasonal predilection can be misdiagnosed as CH.[21] The continuous background pain is the clinical clue in such patients, and a dramatic response to indomethacin clinch the diagnosis of HC.

Migrainous features

The prevalence of at least one migrainous symptom (nausea, vomiting, photophobia, and phonophobia) varies from 17% to 90% (with mean pooled prevalence = 60%). About 56% of patients met the criteria for migraine during the exacerbations.[2] A few patients may have an aura during exacerbations. Visual auras are the most common aura in patients with HC.[22] Other reported auras in HC were sensory and olfactory auras.[23],[24]

Cranial autonomic symptoms (CAS)

Ipsilateral CAS in the trigeminal distribution is a very important accompanying feature of TACs, including HC. However, its position in ICHD criteria has changed over the years. In ICHD-2 criteria, there were six CAS for HC (although there had been 8 CAS for CH and PH; eyelid edema, and forehead and facial sweating were not included for HC). A diagnosis of HC could not be made in the absence of CAS according to ICHD-2.[25] A significant change was made in the ICHD-3β criteria and they recognized 10 different types of CAS: (i) conjunctival injection, (ii) lacrimation, (iii) nasal congestion, (iv) rhinorrhea, (v) ptosis, (vi) miosis, (vii) eyelid edema, (viii) forehead and facial sweating, (ix) forehead and facial flushing, and (x) sensation of fullness in the ear. Moreover, the presence of CAS was not an essential feature as agitation was included as an alternative to CAS in the diagnostic criteria.[26] In the third edition (ICHD-3), two CAS were again removed from the list (forehead and facial flushing and sensation of fullness in the ear).[1]

The mean prevalence of at least one CAS in HC varies between 57%–100% in different studies. Lacrimation is the most common CAS (33%–77%) in most of the case series. Conjunctival injection, nasal congestion, and rhinorrhea are other common CAS. Sand in eye sensation or itching eye was common in a few studies (up to 35%). Although not included in the criteria, it is considered as a type of CAS.[2]

The number and severity of CAS are related to the intensity of the pain. Severe headache attacks may have a higher number of CAS with higher severity. However, the intensity of CAS in HC is relatively less than those during the attacks of CH and PH. CAS may be mild or barely perceptible in HC, a prospective observation during headache attacks is important before labeling it as “absent.”[10],[16]

Agitation in hemicrania continua

Patients with HC can show restlessness or agitation. Patients find difficulty in staying still during attacks or exacerbations, and rarely lie down comfortably. Rubbing or pressing or holding the aching part (65%) is the most common behavioral abnormality. Other common behavioral abnormalities are rolling on bed/ground (45%), walking back and forth (39%), pacing/rocking (32%), and putting something on the aching part (26%). Suicidal ideation was felt in 10% of patients during exacerbations.[10] The prevalence of restlessness in HC varied from 10%–69% in different studies and it is less than that of PH and CH.[1],[25],[26]

Pathophysiology

Both peripheral and central pathophysiological mechanisms are suggested in HC. A positron emission tomography (PET) study has demonstrated the activation of the contralateral posterior hypothalamus, ipsilateral ventrolateral midbrain, ipsilateral dorsal rostral pons, and bilateral pontomedullary junction. The hypothalamic orexinergic system is the main circuit to regulate the hypothalamus. Somatostatinergic, opioidergic, and serotoninergic circuits also influence the hypothalamus. The hypothalamus controls the trigeminal autonomic reflex (TAR), and the disinhibition of TAR by the hypothalamus leads to various cranial autonomic symptoms.[27],[28]

Diagnosis of hemicrania continua

A suspicion for HC should arise in all cases of side-locked headaches. The diagnosis of HC is made according to the criteria proposed by ICHD-3. However, a diagnosis of primary HC is made once you rule out secondary pathologies.

Secondary HC

There have been about 75 cases of secondary HC in the literature, and it includes more than 25 different pathologies [Table 1]. HC-like headaches may arise from both intracranial and extracranial structures such as the cranium, neck, eyes, nose, sinuses, ears, teeth, mouth, and the other facial or cervical structures, including vessels. [Table 1] shows the common secondary HC (at least 2 cases with each). Posttraumatic headache is the most common cause of secondary HC, followed by postsurgery, dissection, prolactinoma, carcinoma lung, and nasopharyngeal carcinoma.[29],[30],[31],[32],[33],[34],[35],[36],[37],[38],[39],[40],[41],[42],[43],[44],[45],[46],[47] There is one case each with pituitary infarct, internal carotid artery (ICA) aneurysm, venous malformation, vertebral artery dissection, carotid-cavernous fistula, cerebral venous thrombosis, angiolipoma in the temporal region, poststroke, cerebellopontine (CP) angle epidermoid, pineal cyst, idiopathic hypertrophic pachymeningitis, transdermal nitroglycerine, analgesic rebound, HIV, sphenoidal tumor, sphenoid sinusitis, orbital tumor/pseudotumor, exfoliation glaucoma, disc herniation, and vitreous hemorrhage.[2],[31],[48],[49],[50],[51]
Table 1: Secondary hemicrania continua

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Carcinoma lung and nasopharyngeal carcinoma may have HC-like pain. An elderly patient with a smoking habit, short duration of illness, constitutional and respiratory symptoms, and raised erythrocyte sedimentation rate (ESR) should be screened for carcinoma lung.[31],[39],[40],[41]


 » Differential Diagnosis Top


The diagnosis of HC is easy when you recognize both components of HC: (i) continuous background headache and (ii) superimposed severe exacerbations [Figure 1]a. Patients with mild background pain and severe exacerbations may not volunteer about the background pain, and the diagnosis depends on the exacerbations phase [Figure 1]b. As most of the primary headaches have well-defined duration and frequency of attacks, the patient may get a wrong diagnosis if only the duration of exacerbations is taken into account. For example, if the duration is short, the misdiagnosis of PH or CH may be made whereas long-duration exacerbations mimic migraine.

Some patients may have more severe background pain (>7 in VAS), and there may not be many fluctuations. In Cittadini and Goadsby's series, two patients had continuous pain with a severity score of 10.[17] Moreover, patients may have infrequent exacerbations, for example, one attack in a 1–4 month interval. In such cases, physicians and patients may not focus on the exacerbations, and diagnosis will be dependent on the characteristics of background pain and may suggest secondary headaches, atypical facial pain, or new persistent daily headache (NDPH) [Figure 1]c.

Commonly HC is misdiagnosed as migraine (52% by Rossi et al. and 71% by Prakash et al.).[9],[10] [Table 2] highlights the differentiating features between side-locked migraine and HC.
Table 2: A comparison between a side-locked migraine and hemicrania continua

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 » Diagnostic Approach Top


A suspicion for HC (or any TACs) should arise in all cases of side-locked headaches. All TACs share a few unique clinical symptoms, which can be easily remembered by a mnemonic '3A of TACs,[2],[52] which include: (i) “anteriorly located unilateral pain” (orbital, frontal and temporal) pain, (ii) “autonomic symptoms” in the same areas, and (iii) “agitation” during attacks. If all components of 3A are present, the case is most likely one of the types of TACs (after excluding secondary causes). All TACs have short-duration headache episodes, except HC in which the pain is continuous. Therefore, getting a history of continuous background pain is the most important clinical clue for HC. Such a patient needs a trial of indomethacin, and a positive response confirms the diagnosis of HC. Injectable indomethacin (INDOTEST) can also provide a dramatic and immediate response.[53]

Hemicrania continua associated with other primary headache disorders

The association of HC with other primary headaches can be classified into three groups: (i) both HC and other primary headache existing simultaneously, (ii) other primary headache evolve into HC, and (iii) HC evolving into another primary headache. The diagnosis of such an association is important, as patients may need two different types of drugs. CH is the most common headache associated with HC.[2] Patients may need a combination of indomethacin and lithium/verapamil. HC with trigeminal neuralgia (hemicrania continua-tic syndrome) may need a combination of indomethacin and carbamazepine.[54]


 » Management Top


Indomethacin

Indomethacin is the drug of choice and absolute response to indomethacin is included as one of the diagnostic criteria for HC. Treatment is usually started at a dose of 25 mg three times a day (TID), and it is titrated (25 mg TID every 3–5 days) up to 75 mg TID or until the patient gets complete relief.[2] The mean indomethacin dose varies between 75 and 200 mg/day in various case studies. ICHD-3 recognizes the upper therapeutic dose of indomethacin as 225 mg daily.[1] Up to 15% of patients may need a dose higher than 225 mg/day.[16],[17] A response to indomethacin usually starts immediately in all patients. As the mean therapeutic dose is >75 mg in most of the studies, patients show a complete response only after an escalation of the initial dose of indomethacin, and about 50%–80% of patients get a complete response within a week.[10],[16] Patients with a longer duration of headache (i.e. more chronic headaches) may have delayed response to indomethacin, and about 20% of patients show a complete response after 4 weeks of indomethacin administration.[16] About 60%–77% of patients with HC need a lower dose of indomethacin over time.[10],[55] Moreover, about 10%–15% of patients may have a remitting type of HC.[1] Therefore, a dose reduction is recommended in each patient after a certain interval. A gradual reduction of the dose should be done at every 3–6 months interval. Indomethacin is tapered 25 mg every 3–5 days, until either the headache reappears or the patient gets completely off indomethacin. In this way, the remission phase of the patient or the lowest possible dose for a particular patient can be discovered.[2] HC-like headache unresponsive or partially responsive to indomethacin has been reported in the literature. However, ICHD does not recognize this entity.[56]

Alternative medications

About 20%–75% may develop indomethacin-related side effects and may require alternative drugs.[57] Various drugs have been found effective in case reports and open-label studies.[2],[56] The effects of these drugs are not uniform and consistent in every patient. It is difficult to predict which patient will respond to which class of drugs. Topiramate is probably the best alternative to indomethacin. Cyclooxygenase-2 inhibitors (rofecoxib and celecoxib), gabapentin, and melatonin can be other alternatives.[2]

The reappearance of pain on skipping or missing indomethacin and other effective drugs

Headache reappears within a few hours to a few days after missing the effective drugs (indomethacin or others) and a few authors consider it as a “strong testimony” for HC.[58],[59] It may be a clinical clue to identify HC in patients with side-locked headaches, especially in those who did not take indomethacin but there was a complete response in headaches by other drugs. Such patients claim that “response continues as long as they receive the drug.”[10]

Surgical interventions

The modulation of structures involved in the pathogenesis of HC may help in reducing or preventing symptoms of HC. Several surgical approaches have been tried in patients with HC [Table 3].[60],[61],[62],[63],[64],[65],[66],[67],[68],[69],[34],[70],[71],[72],[73],[74],[75] Although the effects of these surgical measures are mixed, they could be used in patients who are intolerant to indomethacin or cannot use indomethacin for the long term because of associate comorbid conditions.
Table 3: Surgical interventions in hemicrania continua

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 » Natural course and prognosis Top


The literature is relatively silent regarding long-term remission in patients with HC. In 1999, Espada et al. reported 10 patients with HC. A follow-up study was available for eight patients (mean follow-up 13 months, range 1–22 months).[76] In three patients, indomethacin could be discontinued (after 3, 7, and 15 months). However, the authors did not report how long these patients had been followed up after discontinuation of indomethacin. Prakash et al. did a long-term prospective study in 31 patients with HC.[10] The mean follow-up was 30 months (± 10.6). The dose reduction of indomethacin was done at every 4-6 months interval. None of the patients were completely off the drug in 2.5 years of follow-up. Indomethacin could be withdrawn in three patients for a limited period. Headaches reappeared in all three patients in 2–5 months. A few authors suggest that it may be a life-long disorder.[2]


 » Conclusion Top


HC represents an intriguing primary headache disorder that is included under TACS. The patients may remain undiagnosed for several years as they may not volunteer the history of continuous background pain and associated CAS. The exacerbations are highly variable in terms of frequency, duration, intensity, and associated clinical symptoms. The exacerbation part mimics several primary headaches and neuralgias. More than 25 secondary pathologies mimic primary HC, and routine investigations may not detect those cases. Hence, neuroimaging is done in all suspected cases of HC. Cases of coexistence of HC with other primary headaches are increasing in number. Although the response to indomethacin is absolute, the immediate reappearance of pain on skipping or missing the drug is well documented.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
 » References Top

1.
Headache Classification Committee of the International Headache Society (IHS). The International Classification of Headache Disorders, 3rd edition (beta version). Cephalalgia 2018;38:629-808.  Back to cited text no. 1
    
2.
Prakash S, Patel P. Hemicrania continua: Clinical review, diagnosis and management. J Pain Res 2017;10:1493-509.  Back to cited text no. 2
    
3.
Medina JL, Diamond S. Cluster headache variant: Spectrum of a new headache syndrome. Arch Neurol 1981;35:705-9.  Back to cited text no. 3
    
4.
Sjaastad O, Spierings EL. Hemicrania continua: Another headache absolutely responsive to indomethacin. Cephalalgia 1984;4:65-70.  Back to cited text no. 4
    
5.
Peres M, Silberstein SD, Nahmias S. Hemicrania continua is not that rare. Neurology 2001;57:948-51.  Back to cited text no. 5
    
6.
Sjaastad O, Bakketeig LS. The rare, unilateral headaches. Vaga study of headache epidemiology. J Headache Pain 2007;8:19-27.  Back to cited text no. 6
    
7.
Prakash S, Rathore C, Makwana P, Dave A. A cross-sectional clinic-based study in patients with side-locked unilateral headache and facial pain. Headache 2016;56:1183-93.  Back to cited text no. 7
    
8.
Wei DY, Moreno-Ajona D, Renton T, Goadsby PJ. Trigeminal autonomic cephalalgias presenting in a multidisciplinary tertiary orofacial pain clinic. J Headache Pain 2019;20:69.  Back to cited text no. 8
    
9.
Rossi P, Faroni J, Tassorelli C, Nappi G. Diagnostic delay and suboptimal management in a referral population with hemicranias continua. Headache 2009;49:227-34.  Back to cited text no. 9
    
10.
Prakash S, Rathore C, Rana K, Joshi H, Patel J, Rawat KS. A long-term prospective observational study in 31 patients with hemicrania continua. Cephalalgia Rep 2019;2:1-8. doi:10.1177/2515816318824694.  Back to cited text no. 10
    
11.
Cortijo E, Guerrero AL, Herrero S, Mulero P, Muñoz I, Pedraza MI, et al. Hemicrania continua in a headache clinic: Referral source and diagnostic delay in a series of 22 patients. J Headache Pain 2012;13:567-9.  Back to cited text no. 11
    
12.
de Moura LM, Bezerra JM, Fleming NR. Treatment of hemicranias continua: Case series and literature review. Rev Bras Anestesiol 2012;62:173-87.  Back to cited text no. 12
    
13.
Bordini C, Antonaci F, Stovner LJ, Chrader H, Sjaastad O et al. “Hemicrania continua”: A clinical review. Headache 1991;31:20-6.   Back to cited text no. 13
    
14.
Pareja JA, Palomo T, Gorriti MA, Pareja J, Espejo J. “Hemicrania Episodica”- A new type of headache or a pre-chronic stage of hemicrania continua? Headache 1990;30:344-6.  Back to cited text no. 14
    
15.
Weatherall MW, Bahra A. Familial hemicrania continua. Cephalalgia 2011;31:245-9.  Back to cited text no. 15
    
16.
Prakash S, Golwala P. A proposal for revision of hemicrania continua diagnostic criteria based on critical analysis of 62 patients. Cephalalgia 2012;32:860-8.  Back to cited text no. 16
    
17.
Cittadini E, Goadsby PJ. Hemicrania continua: A clinical study of 39 patients with diagnostic implications. Brain 2010;133:1973-86.  Back to cited text no. 17
    
18.
Prakash S, Shah ND, Chavda BV. Unnecessary extractions in patients with hemicrania continua: Case reports and implication for dentistry. J Orofac Pain 2010;24:408-11.  Back to cited text no. 18
    
19.
Ziegeler C, May A. facial presentations of migraine, TACs, and other paroxysmal facial pain syndromes. Neurology 2019;93:e1138-47.  Back to cited text no. 19
    
20.
Hryvenko I, Cervantes-Chavarría AR, Law AS, Nixdorf DR. Hemicrania continua: Case series presenting in an orofacial pain clinic. Cephalalgia 2018;38:1950-9.  Back to cited text no. 20
    
21.
Prakash S, Rawat KS. A case of remitting hemicrania continua with seasonal variation and clustering: A diagnostic confusion with cluster headache. BMJ Case Rep 2019;12:e229650.  Back to cited text no. 21
    
22.
Peres M, Slow HC, Rozen TD. Hemicrania continua with aura. Cephalalgia 2002;22:246-8.  Back to cited text no. 22
    
23.
Palmieri A, Mainardi F, Maggioni F, Dainese F, Zanchin G. Hemicrania continua evolving from migraine with aura: Clinical evidence of a possible correlation between two forms of primary headache. Cephalalgia 2004;24:1007-10.  Back to cited text no. 23
    
24.
Kuhn J, Kuhn KF, Cooper-Mahkorn D, Bewermeyer H. Remitting form of hemicrania continua: Two new cases exhibiting one unusual autonomic feature. Headache 2005;45:759-62.  Back to cited text no. 24
    
25.
Headache Classification Subcommittee of the International Headache Society. The International classification of headache disorders: 2nd ed. Cephalalgia 2004;24(Suppl 1):1-160.  Back to cited text no. 25
    
26.
Headache Classification Committee of the International Headache Society (IHS). The International classification of headache disorders, 3rd edition (beta version). Cephalalgia 2013;33:629-808.  Back to cited text no. 26
    
27.
Prakash S, Hansen JM. Mechanisms of cluster headache and other trigeminal autonomic cephalalgias. In: Martelletti P, Timothy J, Steiner TJ, editors. Handbook of Headache: Practical Management. 1st ed. Berlin: Springer Verlag; 2011. p. 330-40.  Back to cited text no. 27
    
28.
Matharu MS, Cohen AS, McGonigle DJ, Ward N, Frackowiak RS, Goadsby PJ. Posterior hypothalamic and brainstem activation in hemicrania continua. Headache 2004;44:747-61.  Back to cited text no. 28
    
29.
Finkel AG, Yerry JA, Klaric JS, Ivins BJ, Scher A, Choi YS. Headache in military service members with a history of mild traumatic brain injury: A cohort study of diagnosis and classification. Cephalalgia 2017;37:548-59.  Back to cited text no. 29
    
30.
Lay CL, Newman LC. Posttraumatic hemicrania continua. Headache 1999;39:275-9.  Back to cited text no. 30
    
31.
Prakash S, Shah ND, Soni RK. Secondary hemicrania continua: Case reports and a literature review. J Neurol Sci 2009;280:29-34.  Back to cited text no. 31
    
32.
Evans RW, Lay CL. Posttraumatic hemicrania continua? Headache 2000;40:761-2.  Back to cited text no. 32
    
33.
Wheeler SD. Hemicrania continua in African Americans. J Natl Med Assoc 2002;94:901-7.  Back to cited text no. 33
    
34.
Schwedt TJ, Dodick DW, Trentman TL, Zimmerman RS. Occipital nerve stimulation for chronic cluster headache and hemicrania continua: Pain relief and persistence of autonomic features. Cephalalgia 2006;26:1025-7.  Back to cited text no. 34
    
35.
Rogalewski A, Evers S. Symptomatic hemicrania continua after internal carotid artery dissection. Headache 2005;45:167-9.  Back to cited text no. 35
    
36.
Ashkenazi A, Abbas MA, Sharma DK, Silberstein SD. Hemicrania continua-like headache associated with internal carotid artery dissection may respond to indomethacin. Headache 2007;47:127-30.  Back to cited text no. 36
    
37.
Brilla R, Pawlowski M, Evers S. Hemicrania continua in carotid artery dissection–symptomatic cases or linked pathophysiology? Cephalalgia 2018;38:402-5.  Back to cited text no. 37
    
38.
Gantenbein AR, Sarikaya H, Riederer F, Goadsby PY. Postoperative hemicrania continua like headache – A case series. J Headache Pain 2015;16:41.  Back to cited text no. 38
    
39.
Levy MJ, Matharu MS, Goadsby PJ. Prolactinomas, dopamine agonists and headache: Two case reports. Eur J Neurol 2003;10:169-73.  Back to cited text no. 39
    
40.
Wang SJ, Hung CW, Fuh JL, Lirng JF, Hwu CM. Cranial autonomic symptoms in patients with pituitary adenoma presenting with headaches. Acta Neurol Taiwan 2009;18:104-12.  Back to cited text no. 40
    
41.
Eross EJ, Swanson JW, Dodick DW. Hemicrania continua: An indomethacin responsive case with an underlying malignant etiology. Headache 2002;42:527-9.  Back to cited text no. 41
    
42.
Evans RW. Hemicrania continua-like headache due to non-metastatic lung cancer— A vagal cephalalgia. Headache 2007;47:1349-51.  Back to cited text no. 42
    
43.
Robbins MS, Grosberg BM. Hemicrania continua-like headache from metastatic lung cancer. Headache 2010;50:1055-6.  Back to cited text no. 43
    
44.
Zhang Y, Wang D, He Z, Wu Q, Zhou J. Hemicrania continua-like headache secondary to nasopharyngeal carcinoma: A case report. Cephalalgia 2017;37:1005-7.  Back to cited text no. 44
    
45.
Spitz M, Peres MF. Hemicrania continua postpartum. Cephalalgia 2004;24:603-4.  Back to cited text no. 45
    
46.
Prakash S, Dholakia SY. Hemicrania continua-like headache with leprosy: Casual or causal association? Headache 2008;48:1132-4.  Back to cited text no. 46
    
47.
Ferreira KS, Freitas DJ, Speciali JG. Is there a relation between hemicrania continua and leprosy? Indian J Lepr 2012;84:317-20.  Back to cited text no. 47
    
48.
Tabata H, Kitaguchi H. Hemicrania continua subsequent to vertebral artery dissection: A case report. J Stroke Cerebrovasc Dis 2019;28:104443.  Back to cited text no. 48
    
49.
Arnold Fiebelkorn C, Lanzino G, Chen JJ, Brinjikji W, Eckel LJ, Boes CJ. Carotid cavernous fistula mimicking hemicrania continua: A case report. Headache 2019;59:1365-9.  Back to cited text no. 49
    
50.
Russo A, Silvestro M, Cirillo M, Tessitore A, Tedeschi G. Idiopathic hypertrophic pachymeningitis mimicking hemicrania continua: An unusual clinical case. Cephalalgia 2018;38:804-7.  Back to cited text no. 50
    
51.
Noma N, Iwasa M, Young A, Ikeda M, Hsu YC, Yamamoto M, et al. Orofacial pain and headaches associated with exfoliation glaucoma. J Am Dent Assoc 2017;148:936-40.  Back to cited text no. 51
    
52.
Prakash S, Rathore C. Side-locked headaches: An algorithm-based approach. J Headache Pain 2016;17:95.  Back to cited text no. 52
    
53.
Antonaci F, Pareja JA, Caminero AB, Sjaastad O. Chronic paroxysmal hemicrania and hemicrania continua. Parenteral indomethacin: The 'indotest'. Headache 1998;38:122-8.  Back to cited text no. 53
    
54.
Prakash S, Rathore C. Two cases of hemicrania continua-trigeminal neuralgia syndrome: Expanding the spectrum of trigeminal autonomic cephalalgia-Tic (TAC-TIC) syndrome. Headache 2017;57:472-7.  Back to cited text no. 54
    
55.
Pareja JA, Caminero AB, Franco E, Casado JL, Pascual J, Sánchez del Río M. Dose, efficacy and tolerability of long-term indomethacin treatment of chronic paroxysmal hemicrania and hemicrania continua. Cephalalgia 2001;21:906-10.  Back to cited text no. 55
    
56.
Prakash S, Shah ND, Bhanvadia RJ. Hemicrania continua unresponsive or partially responsive to indomethacin: Does it exist? A diagnostic and therapeutic dilemma. J Headache Pain 2009;10:59-63.  Back to cited text no. 56
    
57.
Prakash S, Husain M, Sureka D, Shah N, Shah N. Is there need to search for alternatives to indomethacin for hemicrania continua? Case reports and a review. J Neurol Sci 2009;277:187-90.  Back to cited text no. 57
    
58.
Prakash S, Shah ND. Hemicrania continua unresponsive to indomethacin do exist. Cephalalgia 2010;30:123-5.  Back to cited text no. 58
    
59.
Antonaci F and Sjaastad O. Hemicrania continua. Amsterdam: Elsevier B.V, Handbook of Clinical Neurology 2010;97:483-87.   Back to cited text no. 59
    
60.
Miller S, Lagrata S, Matharu M. Multiple cranial nerve blocks for the transitional treatment of chronic headaches. Cephalalgia 2019;39:1488-99.  Back to cited text no. 60
    
61.
Guerrero ÁL, Herrero-Velázquez S, Peñas ML, Mulero P, Pedraza MI, Cortijo E, et al. Peripheral nerve blocks: A therapeutic alternative for hemicrania continua. Cephalalgia 2012;32:505-8.  Back to cited text no. 61
    
62.
Afridi SK, Shields KG, Bhola R, Goadsby PJ. Greater occipital nerve injection in primary headache syndromes – Prolonged effects from a single injection. Pain 2006;122:126-9.  Back to cited text no. 62
    
63.
Antonaci F, Pareja JA, Caminero AB, Sjaastad O. Chronic paroxysmal hemicrania and hemicrania continua: Anaesthetic blockades of pericranial nerves. Funct Neurol 1997;12:11-5.  Back to cited text no. 63
    
64.
Androulakis XM, Krebs KA, Ashkenazi A. Hemicrania continua may respond to repetitive sphenopalatine ganglion block: A case report. Headache 2016;56:573-9.  Back to cited text no. 64
    
65.
Beams JL, Kline MT, Rozen TD. Treatment of hemicrania continua with radiofrequency ablation and long-term follow-up. Cephalalgia 2015;35:1208-13.  Back to cited text no. 65
    
66.
Weyker P, Webb C, Mathew L. Radiofrequency ablation of thesupra-orbital nerve in the treatment algorithm of hemicrania continua. Pain Physician 2012;15:E719-24.  Back to cited text no. 66
    
67.
Miller S, Watkins L, Matharu MS. Treatment of intractable hemicrania continua by occipital nerve stimulation. J Neurol Neurosurg Psychiatry 2017;88:805-6.  Back to cited text no. 67
    
68.
Burns B, Watkins L, Goadsby PJ. Treatment of hemicrania continua by occipital nerve stimulation with a bion device: Long-term follow-up of a crossover study. Lancet Neurol 2008;7:1001-12.  Back to cited text no. 68
    
69.
Schwedt TJ, Dodick DW, Hentz J, Trentman TL, Zimmerman RS. Occipital nerve stimulation for chronic headache – Long-term safety and efficacy. Cephalalgia 2007;27:153-7.  Back to cited text no. 69
    
70.
Trimboli M, Al-Kaisy A, Andreou AP, Murphy M, Lambru G. Non-invasive vagus nerve stimulation for the management of refractory primary chronic headaches: A real-world experience. Cephalalgia 2018;38:1276-85.  Back to cited text no. 70
    
71.
Eren O, Straube A, Schöberl F, Schankin C. Hemicrania continua: Beneficial effect of non-invasive vagus nerve stimulation in a patient with a contraindication for indomethacin. Headache 2017;57:298-301.  Back to cited text no. 71
    
72.
Nesbitt A, Marin J, Goadsby P. Treatment of hemicrania continua by non-invasive vagus nerve stimulation in 2 patients previously treated with occipital nerve stimulation. J Headache Pain 2013;14(Suppl 1):P230.  Back to cited text no. 72
    
73.
Miller S, Correia F, Lagrata S, Matharu MS. Onabotulinumtoxin A for hemicrania continua: Open label experience in 9 patients. J Headache Pain 2015;16:19.  Back to cited text no. 73
    
74.
Khalil M, Ahmed F. Hemicrania continua responsive to botulinum toxin type a: A case report. Headache 2013;53:831-3.  Back to cited text no. 74
    
75.
Garza I, Cutrer FM. Pain relief and persistence of dysautonomic features in a patient with hemicrania continua responsive to botulinum toxin type A. Cephalalgia 2010;30:500-3.  Back to cited text no. 75
    
76.
Espada F, Escalza I, Morales-Asin F, Navas I, Inignez C, Mauri JA. Hemicrania continua: Nine new cases. Cephalalgia 1999;19:442. Abstract.   Back to cited text no. 76
    


    Figures

  [Figure 1]
 
 
    Tables

  [Table 1], [Table 2], [Table 3]



 

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