SUN: Short-Lasting Unilateral Neuralgiform Headache Attacks

Cluster Headache, SUNCT, and SUNA

OBJECTIVE

This article reviews the epidemiology, clinical features, differential diagnosis, pathophysiology, and management of three types of trigeminal autonomic cephalalgias: cluster headache (the most common), short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT), and short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA).

LATEST DEVELOPMENTS

The first-line treatments for trigeminal autonomic cephalalgias have not changed in recent years: cluster headache is managed with oxygen, triptans, and verapamil, and SUNCT and SUNA are managed with lamotrigine. However, new successful clinical trials of high-dose prednisone, high-dose galcanezumab, and occipital nerve stimulation provide additional options for patients with cluster headache. Furthermore, new genetic and imaging tests in patients with cluster headache hold promise for a better understanding of its pathophysiology.

ESSENTIAL POINTS

The trigeminal autonomic cephalalgias are a group of diseases that appear similar to each other and other headache disorders but have important differences. Proper diagnosis is crucial for proper treatment.

A brief diagnostic screen for cluster headache: Creation and initial validation of the Erwin Test for Cluster Headache

OBJECTIVE

To use 1) newly generated data, 2) existing evidence, and 3) expert opinion to create and validate a new cluster headache screening tool.

METHODS

In phase 1 of the study, we performed a prospective study of an English translation of an Italian screen on 95 participants (45 with cluster headache, 17 with other trigeminal autonomic cephalalgias, 30 with migraine, and 3 with trigeminal neuralgia). In phase 2, we performed a systematic review in PubMed of all studies until September 2019 with diagnostic screening tools for cluster headache. In phase 3, a 6-person panel of cluster headache patients, research coordinators, and headache specialists analyzed the data from the first two phases to generate a new diagnostic screening tool. Finally, in phase 4 this new screen was validated on participants at a single headache center (all diagnoses) and through research recruitment (trigeminal autonomic cephalalgias only, as recruitment was essential but was otherwise low).

RESULTS

In total, this study included 319 unique participants including 109 cluster headache participants (95 total participants/45 cluster headache participants in phase 1, and 224 total participants/64 cluster headache participants in phase 4). It also found 123 articles on potential screening tools in our systematic review. In phase 1, analysis of the English translation of an Italian screen generated 7 questions with high sensitivity and specificity against migraine, trigeminal neuralgia, and other trigeminal autonomic cephalalgias, but had grammatical and other limitations as a general screening tool. In phase 2, the systematic review revealed nine studies that met inclusion criteria as diagnostic screening tools for cluster headache, including four where sensitivity and specificity were available for individual questions or small groups of questions. In phase 3, this data was reviewed by the expert panel to generate a brief (6-item), binary (yes/no), written screening test. In phase 4, a total of 224 participants completed the new 6-item screening test (81 migraine, 64 cluster headache, 21 other trigeminal autonomic cephalalgias, 35 secondary headaches, 7 neuralgias, 5 probable migraine, and 11 other headache disorders). Answers to the 6 items were combined in a decision tree algorithm and three items had a sensitivity of 84% (confidence interval or 95% confidence interval 73-92%), specificity of 89% (95% confidence interval 84-94%), positive predictive value of 76% (95% confidence interval 64-85%), and negative predictive value of 93% (95% confidence interval 88-97%) for the diagnosis of cluster headache. These three items focused on headache intensity, duration, and autonomic features.

CONCLUSION

The 3-item Erwin Test for Cluster Headache is a promising diagnostic screening tool for cluster headache.

The changing face of trigeminal neuralgia-A narrative review

OBJECTIVE

This narrative review aims to update the reader on the new classification of trigeminal neuralgia (TN), clinical signs, pathophysiologic evidence, and their implications on management. This review is based on the authors' collective experience and knowledge of the literature in addition to a literature search.

BACKGROUND

In recent years, the phenotype of TN has been intensively studied leading to discrete groups of patients. These include patients with TN with additional continuous pain, and patients with and without neurovascular compression of the trigeminal dorsal root entry zone. A number of associated clinical signs such as tearing and sensory changes need further research.

METHODS

The literature on TN was searched in PubMed with the aims of providing evidence for the recently published third edition of the International Classification of Headache Disorders (ICHD) and update the clinical phenotype and management of the TN subcategories.

RESULTS

The ICHD's new classification for TN is based on reliable clinical data, imaging, and neurophysiologic studies. The TN classification reflects current knowledge and has improved the possibility for clinicians to choose adequate management options. However, there is a lack of effective, safe drugs for the management of TN and sparse, robust data on neurosurgical options.

CONCLUSION

Research into all aspects of TN-diagnosis, pharmacotherapy, surgery, long-term management prognosis, and natural history-is needed. Research should adhere to the ICHD's schema for TN. Improved drugs are needed along with rigorous research into surgical options and their efficacy for different subtypes of TN.

SUNCT and SUNA: An Update

Background

Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) and short-lasting unilateral neuralgiform headache with autonomic symptoms (SUNA) are rare and disabling primary headache disorders that are subtypes of Short-lasting unilateral neuralgiform headache attacks (SUNHA).

Aim

The aim of this narrative review was to provide a comprehensive update on headache phenotype, pathophysiology, and various treatment options available for SUNCT and SUNA.

Methods

References for this review were identified by searches of articles published in the English language in PubMed between 1978 and October 2020 using "short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT)", "short-lasting unilateral neuralgiform headache with autonomic symptoms (SUNA)", "short-lasting unilateral neuralgiform headache attacks (SUNHA)", "trigeminal autonomic cephalalgias" as keywords in various combinations.

Results

Of a potential 1103 articles, seven case series describing clinical characteristics of SUNCT/SUNA patients were identified for this review. For symptomatic/secondary SUNCT/SUNA, 53 individual case reports, and one case series were reviewed. One placebo-controlled trial and 11 open-label case series that evaluated various medical and surgical treatments in SUNCT/SUNA were also reviewed. Available literature suggests that SUNCT and SUNA are subtypes of the same disorder characterized by severe side locked short duration headache with ipsilateral prominent cranial autonomic symptoms and signs. Pathophysiology may involve both peripheral and central mechanisms. Lamotrigine is the most effective preventive therapy while intravenous lidocaine is the most efficacious drug as transitional therapy for severe disabling attacks. Surgical options including microvascular decompression in those having neurovascular conflict, occipital nerve stimulation, and hypothalamic deep brain stimulation can be alternative treatment options for medically refractory patients.

SUNCT/SUNA: Case series presenting in an orofacial pain clinic

AIM

Little is known about short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) and short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA). We present our experience with SUNCT/SUNA patients to aid identification and management of these disorders.

METHODS

A retrospective review of patient records of one orofacial pain clinic was performed. Inclusion criteria was a diagnosis of SUNCT/SUNA confirmed with at least one follow-up visit.

RESULTS

Six of the 2464 new patients seen between 2015-2018 met the selection criteria (SUNCT n = 2, SUNA n = 4). Gender distribution was one male to one female and average age of diagnosis was 52 years (range 26-62). Attacks were located in the V1/V2 trigeminal distributions, and five patients reported associated intraoral pain. Pain quality was sharp, shooting, and burning with two patients reporting "numbness". Pain was moderate-severe in intensity, with daily episodes that typically lasted for seconds. Common autonomic features were lacrimation, conjunctival injection, rhinorrhea, and flushing. Frequent triggers were touching the nose or a specific intraoral area. Lamotrigine and gabapentin were commonly used as initial therapy.

CONCLUSIONS

Differentiating between SUNCT/SUNA does not appear to be clinically relevant. Presenting symptoms were consistent with those published, except 5/6 patients describing intraoral pain and two patients describing paresthesia.

The fifth cranial nerve in headaches

The fifth cranial nerve is the common denominator for many headaches and facial pain pathologies currently known. Projecting from the trigeminal ganglion, in a bipolar manner, it connects to the brainstem and supplies various parts of the head and face with sensory innervation. In this review, we describe the neuroanatomical structures and pathways implicated in the sensation of the trigeminal system. Furthermore, we present the current understanding of several primary headaches, painful neuropathies and their pharmacological treatments. We hope that this overview can elucidate the complex field of headache pathologies, and their link to the trigeminal nerve, to a broader field of young scientists.

Facial Pain: A Comprehensive Review and Proposal for a Pragmatic Diagnostic Approach

BACKGROUND

Facial pain, alone or combined with other symptoms, is a frequent complaint. Moreover, it is a symptom situated at, more than any other pain condition, a crosspoint where several disciplines meet, for example, dentists; manual therapists; ophthalmologists; psychologists; and ear-nose-throat, pain, and internal medicine physicians besides neurologists and neurosurgeons. Recently, a new version of the most widely used classification system among neurologists for headache and facial pain, the International Classification of Headache Disorders, has been published.

OBJECTIVE

The aims of this study were to provide an overview of the most prevalent etiologies of facial pain and to provide a generic framework for the neurologist on how to manage patients presenting with facial pain.

METHODS

An overview of the different etiologies of facial pain is provided from the viewpoint of the respective clinical specialties that are confronted with facial pain. Key message: Caregivers should "think outside their own box" and refer to other disciplines when indicated. If not, a correct diagnosis can be delayed and unnecessary treatments might be given. The presented framework is aimed at excluding life- or organ-threatening diseases, providing several clinical clues and indications for technical investigations, and ultimately leading to the correct diagnosis and/or referral to other disciplines.

Cranial Neuralgias

PURPOSE OF REVIEW

This article describes the clinical features and diagnostic criteria, pathophysiology (when known), and treatment strategies of the major cranial neuralgias.

RECENT FINDINGS

Abnormal vascular loops compressing cranial nerves are the most common known pathogenesis associated with the primary neuralgias.

SUMMARY

The most frequently encountered primary neuralgias are trigeminal neuralgia, occipital neuralgia, and, rarely, glossopharyngeal neuralgia. Nervus intermedius neuralgia is even more rare. All neuralgias merit a careful workup for secondary causes. Drug treatment generally relies on antiepileptic drugs, antidepressants, and baclofen. OnabotulinumtoxinA can be useful in treating some cranial neuralgias. Surgical and invasive treatments include ablation, gamma knife treatment, and microvascular decompression.

An unusual case of short-lasting unilateral neuralgiform headache attacks

BACKGROUND

Short-lasting unilateral neuralgiform headaches include those with conjunctival injection and tearing and with cranial autonomic symptoms. Most frequently reported as idiopathic, there is a growing number of symptomatic cases described.

CASE REPORT

A 57-year old man presented a 16-year history of right hemifacial short-lasting pain attacks accompanied by ipsilateral autonomic symptoms and simultaneous malar contractions. Brain MRI disclosed a right acoustic neuroma compressing the right facial nerve and a venous developmental anomaly perpendicular to the right facial nerve root entry zone, without lesions affecting the trigeminal nerve. He was started on lamotrigine, resulting in complete remission of pain attacks, autonomic signs and facial contractions.

CONCLUSIONS

This patient presents a typical short-lasting unilateral neuralgiform headache with response to lamotrigine. The uniqueness of the case is the co-occurring malar contractions, evocative of facial nerve involvement. We speculate whether facial nerve compression renders this nerve more susceptible to triggering during a short-lasting unilateral neuralgiform headache attack.

Primary Headaches

The primary headaches are composed of multiple entities that cause episodic and chronic head pain in the absence of an underlying pathologic process, disease, or traumatic injury. The most common of these are migraine, tension-type headache, and the trigeminal autonomic cephalalgias. This article reviews the clinical presentation, pathophysiology, and treatment of each to help in differential diagnosis. These headache types share many common signs and symptoms, thus a clear understanding of each helps prevent a delay in diagnosis and inappropriate or ineffective treatment. Many of these patients seek dental care because orofacial pain is a common presenting symptom.

Cluster Headache and Other Trigeminal Autonomic Cephalalgias

PURPOSE OF REVIEW

This article covers the clinical features, differential diagnosis, and management of the trigeminal autonomic cephalalgias (TACs). The TACs are composed of five diseases: cluster headache, paroxysmal hemicrania, short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT), short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA), and hemicrania continua.

RECENT FINDINGS

New classifications for the TACs have two important updates; chronic cluster headache is now defined as remission periods lasting less than 3 months (formerly less than 1 month), and hemicrania continua is now classified as a TAC (formerly classified as other primary headache). The first-line treatments of TACs have not changed in recent years: cluster headache is managed with oxygen, triptans, and verapamil; paroxysmal hemicrania and hemicrania continua are managed with indomethacin; and SUNCT and SUNA are managed with lamotrigine. However, advancements in neuromodulation have recently provided additional options for patients with cluster headache, which include noninvasive devices for abortive therapy and invasive devices for refractory cluster headache. Patient selection for these devices is key.

SUMMARY

The TACs are a group of diseases that appear similar to each other and to other headache disorders but have important differences. Proper diagnosis is crucial for proper treatment. This article reviews the pathophysiology, epidemiology, differential diagnosis, and treatment of the TACs.

Classification of Trigeminal Autonomic Cephalalgia: What has Changed in International Classification of Headache Disorders-3 Beta?

The term “Trigeminal Autonomic Cephalalgia (TAC)” was first coined by Goadsby and Lipton[1] to include a group of relatively rare primary headache disorders characterized by moderate to severe, short-lived head pain in the trigeminal distribution with unilateral cranial parasympathetic autonomic features, such as lacrimation, rhinorrhea, conjunctival injection, eyelid edema, and ptosis. In the current International Classification of Headache Disorders (ICHD-3 beta),[2] the TAC group includes cluster headache (CH), paroxysmal hemicrania (PH), short-lasting unilateral neuralgiform headache attacks (SUNHAs) and their 2 subforms - SUNHAs with conjunctival injection and tearing (SUNCT), SUNHAs with cranial autonomic symptoms (SUNA). Hemicrania Continua (HC) is also now included in the TAC group. Although the entities included under TACs seem broadly similar, they differ in attack duration, frequency and their response to different treatments. At one end of the spectrum lies CH, the prototypic TAC where the duration of attacks is the longest and at the other end is the SUNCT syndrome where the duration is shortest. There is some overlap across the entities; they are not difficult to recognize and subclassify. The umbrella term “TAC” for the short-lasting headaches with autonomic features was for the first time introduced in The ICHD, 2^nd edition (ICHD-2) published in 2004.[3] The beta version of the 3^rd edition of The ICHD[2] was published in 2013. Headache classification being an evolving process, there have been some changes within the TAC group between ICHD-2 and ICHD-3 beta.[45] Diagnostic criteria have been revised to reflect pathophysiological and clinical observations. Neuroimaging has provided insights into the pathophysiology of TACs. Functional neuroimaging has helped to elucidate key structures activated during attacks of TACs. Correct diagnosis remains the key to correct management of the TACs because treatment options vary. The aim of this article will be to highlight the changes in ICHD-3 beta to this group and to emphasize the clinical implications of these changes. Description of individual entities included under TACs are included elsewhere and will therefore not be detailed here.