Transient side shift of cluster headache attacks after unilateral greater occipital nerve injection

Beyond coincidence: a case series on the clinical course of coinciding cluster headache and short-lasting unilateral neuralgiform headache attacks

Introduction

Limited research has been conducted on co-occurring cluster headache and short-lasting unilateral neuralgiform headache attacks (SUNHA).

Objectives

This case series aims to explore whether the observed overlap of cluster headache and SUNHA reflects a coincidental co-occurrence or suggests a shared underlying mechanism while also providing insights to improve diagnosis and management of these patients.

Methods

A retrospective case series of 10 patients with a diagnosis of both cluster headache and SUNHA.

Results

Two patients exhibited simultaneous onset of cluster headache and SUNHA (concurrent cluster-SUNHA), whereas the remaining 8 had consecutive cluster-SUNHA. Overlapping localization of pain and autonomic symptoms were observed in 9 of 10 cases. Magnetic resonance imaging was performed in 8 patients, revealing an ipsilateral trigeminal neurovascular conflict in half of them. Four patients underwent microvascular decompression, which exhibited varying efficacy on both cluster headache and SUNHA.

Conclusion

This study constitutes the most extensive description to date of individuals diagnosed with both cluster headache and SUNHA. The observed co-occurrence of these headache types could suggest a pathophysiological relationship between the 2, which might be explained by a bidirectional interaction between posterior hypothalamic function and trigeminal root demyelination. The role of a trigeminal neurovascular conflict seems likely in this context, with dedicated magnetic resonance imaging being the optimal method for its identification. The potential role of microvascular decompression as a treatment in cluster-SUNHA cases where such a conflict is identified warrants further investigation.

15. Cluster Headache

INTRODUCTION

Cluster headache is a rare primary headache disorder characterized by excruciating unilateral pain around the eye, lasting between 15 and 180 min, accompanied by ipsilateral cranial autonomic symptoms. Cluster headache is classified into two forms: episodic and chronic, with chronic cluster headache defined by pain-free intervals of less than 3 months between bouts. Both drug-based and invasive treatments are available for abortive and preventive purposes. Treatment selection depends on individual efficacy and tolerance, with invasive options considered when pharmacological treatments prove ineffective.

METHODS

This narrative review summarizes the literature on common practice and the evidence in the treatment of cluster headache.

RESULTS

Oxygen therapy and subcutaneous sumatriptan are the most effective abortive treatments for cluster headache. Oral corticosteroid tapering regimens can be used as bridging therapy. Verapamil, lithium, topiramate, and CGRP antagonists are potential preventive medication options. Greater occipital nerve (GON) injections and radiofrequency (RF) therapy can be used as preventive treatments, though their effects are often temporary. For refractory chronic cluster headache, occipital nerve stimulation (ONS) has proven to be effective. Deep brain stimulation (DBS) may also be considered if all other treatments have failed.

CONCLUSIONS

The management of cluster headache is complex due to the variable efficacy of treatments across different patients and limited evidence.

Pain Lateralization in Cluster Headache and Associated Clinical Factors

BACKGROUND AND PURPOSE

The pain lateralization in cluster headache (CH) may be related to the asymmetry in the functions of the brain hemispheres. The right-sided dominance of pain in CH has been found inconsistently across studies, and so we aimed to characterize this and identify the factors influencing pain lateralization during current and previous bouts.

METHODS

This study enrolled 227 patients from the Korean Cluster Headache Registry between October 2018 and December 2020. We evaluated the side of pain during current and previous bouts, demographic features, and clinical characteristics, including handedness. Multivariable logistic regression analyses were performed to identify factors associated with the side of pain.

RESULTS

The 227 patients with CH included 131 (57.7%) with right-sided pain and 86 (37.9%) with left-sided pain during the current bout (p<0.001). The 189 patients with previous bouts of CH included 86.8% who consistently reported the same side of pain throughout multiple bouts (side-locked pain), with a higher prevalence of pain on the right than the left side (55.0% vs. 31.7%, p<0.001). Multivariable analyses revealed that higher age at diagnosis (odds ratio [OR]=1.045, p=0.031) and shorter CH attacks (OR=0.992, p=0.017) were associated with left-side-locked pain. However, handedness was not associated with the lateralization of left-side-locked pain.

CONCLUSIONS

This study has confirmed the predominance of right-sided pain throughout multiple CH bouts. We found that higher age at diagnosis and shorter CH attacks were associated with left-side-locked pain, suggesting that certain clinical factors are associated with the pain laterality. However, the underlying mechanisms linking these factors to lateralized pain remain unclear and therefore require further investigation.

Transition of cluster headache: Depicting side-changing attacks as a chronic trait in an interview-based follow-up study

BACKGROUND

Cluster headache presents in an episodic and chronic form, between which patients can convert during the course of disease. We aimed to quantify the rate of cluster headache patients changing phenotype within one and five years and investigate the earlier proposed association between chronification and having side-shifting attacks.

METHODS

In total, 430 cluster headache patients well-characterized according to current International Classification of Headache Disorders criteria, who were all participants in a prior transition-study, were re-interviewed in an observational, retrospective, cross-sectional follow-up study design at the Danish Headache Center.

RESULTS

The transition rate for the whole cohort was 6.5% within one year and 19.8% within five years. The risk of becoming chronic if episodic was 4.0% within one year and 12.3% within five years. For conversion from chronic to episodic, the corresponding risk was 11.1% and 25.0%, respectively. Alterations in attack-side were reported in 32% of all chronic patients, generating an odds ratio of 2.24 of being chronic as opposed to episodic if experiencing side-shifting attacks.

CONCLUSIONS

A higher transition rate since the original cross-sectional study demonstrates cluster headache as a non-static condition. Identifying a risk of transition within one and five years, based on current phenotype along with high odds of being chronic when experiencing a shift of attack-side, offers a valuable clinical compass in the dialogue with the patient.