Facial presentations of migraine, TACs, and other paroxysmal facial pain syndromes

The location of pain in cluster headache: Data from the International Cluster Headache Questionnaire

OBJECTIVE

To identify the most common locations of cluster headache pain from an international, non-clinic-based survey of participants with cluster headache, and to compare these locations to other cluster headache features as well as to somatotopic maps of peripheral, brainstem, thalamic, and cortical areas.

BACKGROUND

Official criteria for cluster headache state pain in the orbital, supraorbital, and/or temporal areas, yet studies have noted pain extending beyond these locations, and the occipital nerve appears relevant, given the effectiveness of suboccipital corticosteroid injections and occipital nerve stimulation. Furthermore, cranial autonomic features vary between patients, and it is not clear if the trigeminovascular reflex is dermatome specific (e.g., do patients with maxillary or V2 division pain have more rhinorrhea?). Finally, functional imaging studies show early activation of the posterior hypothalamus in a cluster headache attack. However, the first somatosensory area to be sensitized is unclear; the first area can be hypothesized based on the complete map of pain locations.

METHODS

The International Cluster Headache Questionnaire was an internet-based cross-sectional survey that included a clickable pain map of the face. These data were compared to several other datasets: (1) a meta-analysis of 22 previous publications of pain location in cluster headache (consisting of 6074 patients); (2) four cephalic dermatome maps; (3) participants' survey responses for demographics, autonomic features, and effective medications; and (4) previously published somatotopic maps of the brainstem, thalamus, primary somatosensory cortex, and higher order somatosensory cortex.

RESULTS

One thousand five hundred eighty-nine participants completed the pain map portion of the survey, and the primary locations of pain across all respondents was the orbital, periorbital, and temporal areas with a secondary location in the lower occiput; these primary and secondary locations were consistent with our meta-analysis of 22 previous publications. Of the four cephalic dermatomes (V1, V2, V3, and a combination of C2-3), our study found that most respondents had pain in two or more dermatomes (range 85.7% to 88.7%, or 1361-1410 of 1589 respondents, across the four dermatome maps). Dermatomes did not correlate with their respective autonomic features or with medication effectiveness. The first area to be sensitized in the canonical somatosensory pathway is either a subcortical (brainstem or thalamus) or higher order somatosensory area (parietal ventral or secondary somatosensory cortices) because the primary somatosensory cortex (area 3b) and somatosensory area 1 have discontinuous face and occipital regions.

CONCLUSIONS

The primary pain locations in cluster headache are the orbital, supraorbital, and temporal areas, consistent with the official International Classification of Headache Disorders criteria. However, activation of the occiput in many participants suggests a role for the occipital nerve, and the pain locations suggest that somatosensory sensitization does not start in the primary somatosensory cortex.

Is painful temporomandibular disorder a real headache for many patients?

Temporomandibular disorders (TMDs) and primary headaches are common pain conditions and often co-exist. TMD classification includes the term 'headache secondary to TMD' but this term does not acknowledge the likelihood that primary headache pathophysiology underpins headache causing painful TMD signs and symptoms in many patients. The two disorders have a complex link and we do not fully understand their interrelationship. However, growing evidence shows a significant association between the two disorders. This article reviews the possible connection between temporomandibular disorders and primary headaches, specifically migraine, both anatomically and pathogenetically.

The Burden of Migraine on Quality of Life in Chronic Rhinosinusitis

OBJECTIVE

To determine the impact of comorbid migraine on quality of life (QOL) in chronic rhinosinusitis (CRS).

METHODS

A total of 213 adult patients with CRS were recruited. All participants completed the 22-item Sinonasal Outcome Test (SNOT-22), from which total and validated nasal, ear/facial pain, sleep, and emotional subdomain scores were calculated, and the 5-dimension EuroQol general health questionnaire (EQ-5D), from which the visual analogue scale (VAS) and health utility value (HUV) were calculated. The presence of comorbid migraine was determined by a score of ≥4 on the 5-item Migraine Screen Questionnaire (MS-Q).

RESULTS

Of the participants, 36.2% were screened positive for having comorbid migraine. The mean SNOT-22 score was 64.9 (SD: 18.7) in participants with migraine and 41.5 (SD: 21.1) in participants without migraine (p < 0.001). The mean EQ-5D VAS and HUV were 60.2 (SD: 21.9) and 0.69 (SD: 0.18), respectively, in participants with migraine and 71.4 (SD: 19.4) and 0.84 (SD: 0.13), respectively, in participants without migraine (p < 0.001 for both). Higher ear/facial pain (OR = 1.22, 95% CI: 1.10-1.36, p < 0.001) and sleep (OR = 1.11, 95% CI: 1.04-1.18, p = 0.002) SNOT-22 subdomain scores were positively associated with migraine. The SNOT-22 item scores related to dizziness, reduced concentration, and facial pain, in descending order, were most associated with migraine. The presence of nasal polyps (OR = 0.24, 95% CI: 0.07 - 0.80, p = 0.020) was negatively associated with migraine.

CONCLUSION

Comorbid migraine may be relatively common amongst CRS patients, and its presence is associated with significantly worse QOL. Dizziness as a symptom in CRS patients may be particularly indicative of migraine.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:3279-3284, 2023.

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.

Orofacial Migraine and Other Idiopathic Non-Dental Facial Pain Syndromes: A Clinical Survey of a Social Orofacial Patient Group

Background: Orofacial pain syndromes (OFPs) are a heterogeneous group of syndromes mainly characterized by painful attacks localized in facial and oral structures. According to the International Classification of Orofacial Pain (ICOP), the last three groups (non-dental facial pain, NDFP) are cranial neuralgias, facial pain syndromes resembling primary headache syndromes, and idiopathic orofacial pain. These are often clinical challenges because the symptoms may be similar or common among different disorders. The diagnostic efforts often induce a complex diagnostic algorithm and lead to several imaging studies or specialized tests, which are not always necessary. The aim of this study was to describe the encountered difficulties by these patients during the diagnostic-therapeutic course. Methods: This study was based on the responses to a survey questionnaire, administered to an Italian Facebook Orofacial Patient Group, searching for pain characteristics and diagnostic-therapeutic care courses. The questionnaire was filled out by patients affected by orofacial pain, who were 18 years and older, using a free online tool available on tablets, smartphones, and computers. Results: The sample was composed of 320 subjects (244F/76M), subdivided by age range (18-35 ys: 17.2%; 36-55 ys: 55.0%; >55 ys 27.8%). Most of the patients were affected by OFP for more than 3 years The sample presented one OFP diagnosis in 60% of cases, more than one in 36.2% of cases, and 3.8% not classified. Trigeminal neuralgia is more represented, followed by cluster headaches and migraines. About 70% had no pain remission, showing persisting background pain (VAS median = 7); autonomic cranial signs during a pain attack ranged between 45 and 65%. About 70% of the subjects consulted at least two different specialists. Almost all received drug treatment, about 25% received four to nine drug treatments, 40% remained unsatisfied, and almost 50% received no pharmacological treatment, together with drug therapy. Conclusion: To the authors' knowledge, this is the first study on an OFP population not selected by a third-level specialized center. The authors believe this represents a realistic perspective of what orofacial pain subjects suffer during their diagnostic-therapeutic course and the medical approach often results in unsatisfactory outcomes.

Hemicrania Continua: An Update

PURPOSE OF REVIEW

Hemicrania Continua (HC) is a rare and disabling primary headache disorder that is characterized by persistent, unilateral headache with ipsilateral, cranial autonomic symptoms and restlessness or agitation. The diagnosis requires patients to experience an absolute response to therapeutic doses of indomethacin.

RECENT FINDINGS

HC is diagnosed in in about 1.8% of adult patients who were evaluated for headache in tertiary care services, albeit this estimate should be interpreted with caution. The most prevalent accompanying symptoms appear to be lacrimation, conjunctival injection and restlessness or agitation. However, the available literature is limited by methodologic issues, and the current diagnostic criteria lack clarity on what defines absolute response to indomethacin. More rigorous studies are thus needed to improve our understanding of HC which, in turn, will facilitate better disease management in clinical practice. Here, we provide a comprehensive overview of HC, including its epidemiology, clinical presentation, diagnostic evaluation, and management.

Orofacial Migraine or Neurovascular Orofacial Pain from Pathogenesis to Treatment

The purpose of the present study is to examine possible differences between orofacial migraine (OFM) and neurovascular orofacial pain (NVOP). Facial presentations of primary headache are comparable to primary headache disorders; but occurring in the V2 or V3 dermatomes of the trigeminal nerve. These were classified and recently published in the International Classification of Orofacial Pain, 1st edition (ICOP). A category in this classification is "orofacial pains resembling presentations of primary headaches," which encompasses OFM and NVOP. The differences between NVOP and OFM are subtle, and their response to therapy may be similar. While classified under two separate entities, they contain many features in common, suggesting a possible overlap between the two. Consequently, their separation into two entities warrants further investigations. We describe OFM and NVOP, and their pathophysiology is discussed. The similarities and segregating clinical signs and symptoms are analyzed, and the possibility of unifying the two entities is debated.

Prevalence and clinical features of hemicrania continua in clinic-based studies: A systematic review and meta-analysis

OBJECTIVE

To estimate the relative frequencies of hemicrania continua and its clinical features in adult patients who were evaluated for headache in a clinic-based setting.

METHODS

PubMed and Embase were searched for observational, clinic-based studies published between 1 January 2004 and 1 February 2022, that reported on the relative frequencies of hemicrania continua and its clinical features. Two independent investigators (HMA and SA-K) screened titles, abstracts, and full text-articles. A random-effects meta-analysis was conducted to estimate pooled relative frequencies of hemicrania continua and its clinical features across clinic-based studies.

RESULTS

Eleven clinic-based studies were deemed eligible for inclusion. Of these, eight studies reported on the relative frequency of hemicrania continua among adult patients (n = 9854) who were evaluated for headache in a tertiary care unit. The pooled relative frequency of hemicrania continua was found to be 1.8% (95% CI; 1.0-3.3). Considerable heterogeneity was noted across studies (I² = 89.8%). The three most common symptoms associated with hemicrania continua were lacrimation (72.3%), conjunctival injection (69.8%), and restlessness/agitation (60.2%).

CONCLUSION

The findings of this meta-analysis suggest that there is limited epidemiologic data on the relative frequencies of hemicrania continua and its clinical features. Standardized data acquisition and reporting are needed to estimate prevalence rates more accurately and to better understand epidemiologic patterns. This, in turn, should increase awareness of the impact that hemicrania continua has in clinical practice.

Migraine without aura

Migraine without aura is the commonest form of migraine in both children and adults. The diagnosis is made by applying the International Classification of Headache Disorders Third Edition subsection for migraine without aura (ICHD-3 subsection 1.1). Attacks in patients with migraine without aura are characterized by their polyphasic presentation (prodrome, headache phase, postdromal phase). The symptomatology of attacks is diverse and heterogeneous, with most common symptoms being photophobia, phonophobia, nausea, vomiting, and aggravation of pain by movement. The clinician and researcher who wants to learn about migraine without aura needs to be able to apply the ICHD-3 criteria with its specific symptomatology to make a correct diagnosis, but also needs to be aware about the plethora of symptoms patients may experience. In this chapter, the reader will explore the clinical phenotypical features of migraine without aura.

A Review of Current Perspectives on Facial Presentations of Primary Headaches

Orofacial pain (OFP) has recently been classified and subdivided into a number of groups, similar to headache disorders in the International Classification of Headache Disorders (ICHD). A novel group of OFP has been established whose major feature is that they resemble primary headache disorders occurring in the V2 or V3 dermatomes. These follow the clinical criteria and associated symptoms of the eponymous headache syndromes. Following the recent International Classification of Orofacial Pain (ICOP), three types are differentiated: Headache which spread into the face (type 1), facial pain which replaced headache but maintained the same characteristics and associated symptoms of the former headache (type 2), and de-novo orofacial pain that resembles primary headache types without any involvement of the ophthalmic trigeminal branch (type 3). The epidemiology is unclear: type 1 and 2 are not exactly common, they certainly exist in a notable proportion of headache patients, whereas type 3 may be rather rare. Since effective treatment options are available, it is important for clinicians to recognize such syndromes early to avoid misdiagnosis and unnecessary treatment, which most of these patients still experience. This review gives an up-to-date summary of diagnosis, pathophysiology and treatment of attack-like non-dental facial pain disorders.

Interplay of Oral, Mandibular, and Facial Disorders and Migraine

PURPOSE OF THE REVIEW

Migraine and other primary headache disorders can be localized in the face resembling facial or dental pain, indicating the influence of the trigeminovascular system in the structures innervated by the maxillary (V2) and mandibulary (V3) branches of the trigeminal nerve. Disorders of oral and craniofacial structures may influence primary headache disorders. In the current article, we review the potential links of this interplay.

RECENT FINDINGS

This interplay may be related to anatomy, with the trigeminal pathway and the involvement of both peripheral and central mechanisms, and the presence of calcitonin gene-related peptide (CGRP), a key mediator in migraine pathophysiology. CGRP is also involved in the pathophysiology of temporomandibular disorders (TMD) and their comorbidity with migraine and is also implicated in dental and periodontal pathology. Inflammatory and pathological processes of these structures and their trigeminal nociceptive pathways may influence the trigeminovascular system and consequently may exacerbate or even potentially trigger migraine.

Orofacial pain disorders: An overview and diagnostic approach

Background:

Non-dental orofacial pain disorders are not uncommon, but idiopathic or primary facial pain syndromes are rare. Inadequate recognition of these disorders usually leads to unsatisfactory and unmet treatment needs.

Methods:

We conducted a narrative review with a literature search in PubMed until December 2021, focusing on current guidelines and the recently published International Classification of Orofacial Pain (ICOP).

Results:

In this paper, we provide an updated overview of the common orofacial pain disorders following the ICOP, covering the classification, epidemiology, pathophysiology, clinical approaches, and treatment options. Additionally, we propose a pragmatic approach focusing on the attack duration to improve distinguishing orofacial disorders.

Conclusion:

The introduction of ICOP offers the opportunity to better coordinate and concentrate scientific efforts, which lays the foundation for the identification of the disease mechanism of facial pain disorders and the optimization of the currently still insufficient therapeutic strategies.

Only cervical vertebrae C0-C2, not C3 are relevant for subgrouping migraine patients according to manual palpation and pain provocation: secondary analysis of a cohort study

BACKGROUND

Subgrouping of migraine patients according to the pain response to manual palpation of the upper cervical spine has been recently described. Based on the neuroanatomy and the convergence of spinal and trigeminal nerves in the trigeminocervical complex, the cervical segments C1 to C3 are potentially relevant. To date it has not been investigated whether palpation results of all upper cervical segments are based on one underlying construct which allows combining the results of several tests. Therefore, the aim of this secondary analysis of a cohort study was to determine whether results from all three segments form one construct.

METHODS

Seventy-one migraine patients with chronic or frequent episodic migraine diagnosed according to the international headache society classification version 3 were examined by one physiotherapist. Manual palpation using a posterior to anterior pressure was performed on the upper three cervical vertebrae unilaterally left and right. The results of the palpation according to the patients' responses were combined using factor analysis. In addition, item response theory (IRT) was used to investigate the structure of the response pattern as well as item difficulty and discrimination.

FINDINGS

Factor analysis (principal component) showed that the palpation of C3 loads less onto the underlying construct than the palpation of C1 and C2. Considering a cut-off value > 1.0, the eigenvalues of all three segments do not represent one underlying construct. When excluding the results from C3, remaining items form one construct. The internal consistency of the pain response to palpation of C1 and C2 is acceptable with a Cronbach's alpha of 0.69. IRT analysis showed that the rating scale model fits best to the pain response pattern. The discrimination value (1.24) was equal for all items. Item difficulty showed a clear hierarchical structure between the palpation of C1 and C2, indicating that people with a higher impairment are more likely to respond with referred pain during palpation of C2.

CONCLUSION

Statistical analysis confirms that results from the palpation of the cervical segments C1 and C2 in migraine patients can be combined. IRT analysis confirmed the ordinal pattern of the pain response and showed the higher probability of a pain response during palpation of C2. The pain response to C3 palpation is not relevant for unidimensional IRT analysis.

TRIAL REGISTRATION

German registry of clinical trials (DRKS00015995), Registered 20. December 2018, https://www.drks.de/drks_web/setLocale_EN.do.

Inhibition of Nociception in a Preclinical Episodic Migraine Model by Dietary Supplementation of Grape Seed Extract Involves Activation of Endocannabinoid Receptors

Migraine is associated with peripheral and central sensitization of the trigeminal system and dysfunction of descending pain modulation pathways. Recently, dietary inclusion of grape seed extract (GSE) was shown to inhibit mechanical nociception in a preclinical model of chronic temporomandibular joint disorder, a condition often comorbid with migraine, with the antinociceptive effect mediated, in part, by activation of 5-HT3/7 and GABAB receptors. This study further investigated the mechanisms by which GSE inhibits mechanical nociception in a preclinical model of episodic migraine. Hyperalgesic priming of female and male Sprague Dawley rats was induced by three consecutive daily two-hour episodes of restraint stress. Seven days after the final restraint stress, rats were exposed to pungent odors from an oil extract that contains the compound umbellulone, which stimulates CGRP release and induces migraine-like pain. Some animals received dietary supplementation of GSE in their drinking water beginning one week prior to restraint stress. Changes in mechanical sensitivity in the orofacial region and hindpaw were determined using von Frey filaments. To investigate the role of the endocannabinoid receptors in the effect of GSE, some animals were injected intracisternally with the CB1 antagonist AM 251 or the CB2 antagonist AM 630 prior to odor inhalation. Changes in CGRP expression in the spinal trigeminal nucleus (STN) in response to stress, odor and GSE supplementation were studied using immunohistochemistry. Exposure of stress-primed animals to the odor caused a significant increase in the average number of withdrawal responses to mechanical stimulation in both the orofacial region and hindpaw, and the effect was significantly suppressed by daily supplementation with GSE. The anti-nociceptive effect of GSE was inhibited by intracisternal administration of antagonists of CB1 and CB2 receptors. GSE supplementation inhibited odor-mediated stimulation of CGRP expression in the STN in sensitized animals. These results demonstrate that GSE supplementation inhibits trigeminal pain signaling in an injury-free model of migraine-like pain via activation of endocannabinoid receptors and repression of CGRP expression centrally. Hence, we propose that GSE may be beneficial as a complementary migraine therapeutic.

Characteristics and natural disease history of persistent idiopathic facial pain, trigeminal neuralgia, and neuropathic facial pain

OBJECTIVE

This study aimed to characterize key features, and to assess the clinical development of common nondental facial pain syndromes such as persistent idiopathic facial pain (PIFP), trigeminal neuralgia (TN), and neuropathic facial pain (NEUROP).

METHODS

This is a longitudinal study in which prospective questionnaire data of patients presenting to a specialized outpatient clinic were collected from 2009 to 2019. A telephone interview was conducted with the same patients in 2020 to assess the natural disease history.

RESULTS

n = 411 data sets of patients with chronic facial pain were compiled. Among these were n = 150 patients with PIFP, n = 111 patients with TN, and n = 86 patients with NEUROP. Guideline therapy had not been initiated in 38.7% (58/150; PIFP), 19.8% (22/111; TN), and 33.7% (29/86; NEUROP) patients. Of the patients with PIFP, 99.3% (149/150) had primarily consulted a dentist due to their pain syndrome. The additional telephone interview was completed by 236 out of the 411 patients (57.4%). Dental interventions in healthy teeth had been performed with the intention to treat the pain in many patients (78/94 [83.0%] PIFP; 34/62 [54.8%] TN; 19/43 [44.2%] NEUROP), including dental extractions. 11.3% (7/43) of the patients with TN had never profited from any therapy. In contrast, 29.8% (28/94) of the patients with PIFP had never profited from any therapy. Furthermore, the primary pharmaceutical therapy options suggested by national guidelines were, depending on the substance class, only considered to be effective by 13.8% (13/94; antidepressants) and 14.9% (14/94; anticonvulsants) of the patients with PIFP.

CONCLUSIONS

Facial pain syndromes pose a considerable disease burden. Although treatment of TN seems to be effective in most patients, patients with PIFP and NEUROP report poor effectiveness even when following guideline therapy suggestions. In addition, unwarranted dental interventions are common in facial pain syndromes.

Revised guidelines of the French Headache Society for the diagnosis and management of migraine in adults. Part 1: Diagnosis and assessment

The French Headache Society proposes updated French guidelines for the management of migraine. The first part of these recommendations is focused on the diagnosis and assessment of migraine. First, migraine needs to be precisely diagnosed according to the currently validated criteria of the International Classification of Headache Disorders, 3d version (ICHD-3). Migraine-related disability has to be assessed and we suggest to use the 6 questions of the headache impact test (HIT-6). Then, it is important to check for risk factors and comorbidities increasing the risk to develop chronic migraine, especially frequency of headaches, acute medication overuse and presence of depression. We suggest to use a migraine calendar and the Hospital Anxiety and Depression scale (HAD). It is also necessary to evaluate the efficacy and tolerability of current migraine treatments and we suggest to systematically use the self-administered Migraine Treatment Optimization Questionnaire (M-TOQ) for acute migraine treatment. Finally, a treatment strategy and a follow-up plan have to be proposed. Guidelines for pharmacological and non-pharmacological treatments are presented in the second and third part of the recommendations.

Hemicrania Continua: An Update

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.

Paroxysmal hemifacial pain: A report of two cases

Paroxysmal hemifacial pain (PHFP) is the orofacial counterpart to paroxysmal hemicrania headaches. This paper reports the cases of two patients suffering from episodic attacks of severe unilateral facial pain. In both cases, pain attacks were absolutely responsive to therapeutic doses of indomethacin. Both patients were diagnosed with PHFP, as per the International Classification of Orofacial Pain diagnostic guidelines. The diagnosis of PHFP, and a trial of indomethacin, must be considered in cases of severe unilateral facial pains not clearly explained by more common diagnoses.

Facial pain beyond trigeminal neuralgia

PURPOSE OF REVIEW

Trigeminal neuralgia is a well-known facial pain syndrome with several treatment options. In contrast, non-neuralgiform idiopathic facial pain syndromes are relatively rare, reflected by the fact that, until 2020, no internationally accepted diagnostic classification existed. Like trigeminal neuralgia, these non-dental facial pain syndromes need to be managed by neurologists and pain specialists, but the lack of pathophysiological understanding has resulted in an underrepresented and undertreated patient group.

RECENT FINDINGS

This work provides a brief overview of the most common primary facial pain syndromes, namely, the facial attack-like facial pain, which corresponds to attack-like headache, the persistent idiopathic facial pain (formerly 'atypical facial pain'), and trigeminal neuropathy. What these disorders have in common is that they should all be treated conservatively.

SUMMARY

On the basis of pragmatic classifications, permanent and attack-like primary facial pain can be relatively easily differentiated from one another. The introduction of the new International Classification of Orofacial Pain offers the opportunity to better coordinate and concentrate scientific efforts, so that in the future the therapy strategies that are still inadequate, can be optimized.

Idiopathic Facial Pain Syndromes–An Overview and Clinical Implications

BACKGROUND

Idiopathic facial pain syndromes are relatively rare. A uniform classification system for facial pain became available only recently, and many physicians and dentists are still unfamiliar with these conditions. As a result, patients frequently do not receive appropriate treatment.

METHODS

This article is based on pertinent publications retrieved by a selective search in PubMed, focusing on current international guidelines and the International Classification of Orofacial Pain (ICOP).

RESULTS

The ICOP subdivides orofacial pain syndromes into six major groups, the first three of which consist of diseases of the teeth, the periodontium, and the temporomandibular joint. The remaining three groups (non-dental facial pain) are discussed in the present review. Attack-like facial pain syndromes most closely resemble the well-known primary headache syndromes, such as migraine, but with pain located below the orbitomeatal line. These syndromes are treated in accordance with the guidelines for the corresponding types of headache. Persistent idiopathic facial pain (PIFP) is a chronic pain disorder with persistent, undulating pain in the face and/or teeth, without any structural correlate. Since this type of pain tends to become chronified after invasive procedures, no dental procedures should be performed to treat it if the teeth are healthy; rather, the treatmentis similar to that of neuropathic pain, e.g., with antidepressant and anticonvulsive drugs. Neuropathic facial pain is also undulating and persistent. It is often described as a burning sensation, and neuralgiform attacks may additionally be present. Trigeminal neuralgia is a distinct condition involving short-lasting, lancinating pain of high intensity with a maximum duration of two minutes. The first line of treatment is with medications; invasive treatment options should be considered only if pharmacotherapy is ineffective or poorly tolerated.

CONCLUSION

With the aid of this pragmatic classification system, the clinician can distinguish persistent and attack-like primary facial pain syndromes rather easily and treat each syndrome appropriately.

Chronic Facial Pain: Trigeminal Neuralgia, Persistent Idiopathic Facial Pain, and Myofascial Pain Syndrome-An Evidence-Based Narrative Review and Etiological Hypothesis

Trigeminal neuralgia (TN), the most common form of severe facial pain, may be confused with an ill-defined persistent idiopathic facial pain (PIFP). Facial pain is reviewed and a detailed discussion of TN and PIFP is presented. A possible cause for PIFP is proposed. (1) Methods: Databases were searched for articles related to facial pain, TN, and PIFP. Relevant articles were selected, and all systematic reviews and meta-analyses were included. (2) Discussion: The lifetime prevalence for TN is approximately 0.3% and for PIFP approximately 0.03%. TN is 15-20 times more common in persons with multiple sclerosis. Most cases of TN are caused by neurovascular compression, but a significant number are secondary to inflammation, tumor or trauma. The cause of PIFP remains unknown. Well-established TN treatment protocols include pharmacotherapy, neurotoxin denervation, peripheral nerve ablation, focused radiation, and microvascular decompression, with high rates of relief and varying degrees of adverse outcomes. No such protocols exist for PIFP. (3) Conclusion: PIFP may be confused with TN, but treatment possibilities differ greatly. Head and neck muscle myofascial pain syndrome is suggested as a possible cause of PIFP, a consideration that could open new approaches to treatment.

Migraine presenting as isolated facial pain: A prospective clinical analysis of 58 cases

Background

Sparse evidence has detailed the clinical phenotype of migraine presenting as isolated facial pain. Objective and methods: This was a prospective audit, part of our multidisciplinary facial pain service evaluation, aiming to phenotype patients with migraine presenting as isolated facial pain who attended our service between 2013 and 2018.

Results

Fifty-eight patients were diagnosed with migraine with isolated facial pain (F = 46, 79.3%; mean age: 49.0 years, ± 9.85). Sixty-six percent of patients met the criteria for episodic migraine. The pain was strictly unilateral in 79% and located over the maxillary region in 85% of patients. Associated cranial autonomic signs/symptoms were reported by 45% of our cohort. A percentage of 77% of patients was triptan responders.

Conclusions

Migraine presenting as isolated facial pain is a rare but treatable condition with some distinct demographic and clinical characteristics. It is a diagnosis of exclusion that should be evaluated in specialised multidisciplinary facial pain clinics.

Facial paroxysmal hemicrania associated with the menstrual cycle

Paroxysmal hemicrania (PH) is a rare trigeminal autonomic cephalalgia (TAC) which is usually not associated with the menstrual cycle and usually affects the first trigeminal branch. We present a 47-year-old female patient with a facial variant of PH. For over 11 years, the patient had suffered from 8 to 12 typical PH attacks per day localized in the left maxilla in bouts of 4–9 days solely during her menstruation and ovulation. Single dosages of indomethacin 25 mg showed good efficacy in the prevention of the attacks for several hours. However, the intake of indomethacin had to be ceased due to severe psychiatric side effects. Ibuprofen 400 mg also reliably reduces the attack frequency with the same effectiveness as indomethacin. Attacks of PH can occur solely in the facial region and can be associated with the menstrual cycle which can prove to be a diagnostic challenge. Also, the intake of indomethacin can be limited by psychiatric side effects but can be adequately substituted by ibuprofen.