Cluster headache and other TACs: Pathophysiology and neurostimulation options

The trigeminal autonomic cephalalgias (TACs) are highly disabling primary headache disorders. There are several issues that remain unresolved in the understanding of the pathophysiology of the TACs, although activation of the trigeminal–autonomic reflex and ipsilateral hypothalamic activation both play a central role. The discovery of the central role of the hypothalamus led to its use as a therapeutic target. After the good results obtained with hypothalamic stimulation, other peripheral neuromodulation targets were tried in the management of refractory cluster headache (CH) and other TACs.

Cluster Headache and Other TACs: Pathophysiology and Neurostimulation Options

The trigeminal autonomic cephalalgias (TACs) are highly disabling primary headache disorders. There are several issues that remain unresolved in the understanding of the pathophysiology of the TACs, although activation of the trigeminal–autonomic reflex and ipsilateral hypothalamic activation both play a central role. The discovery of the central role of the hypothalamus led to its use as a therapeutic target. After the good results obtained with hypothalamic stimulation, other peripheral neuromodulation targets were tried in the management of refractory cluster headache (CH) and other TACs.

Splitting Sumatriptan Injections

Some patients have discovered that 2 or 3 mg of sumatriptan aborts an attack. Given the unrealistic quantity limits imposed by most health insurance companies, some have learned how to split a 6 mg injection, allowing them to treat more attacks without exceeding the safe daily limits. One of our members teaches how this is done.

Identifying a gene expression signature of cluster headache in blood

Cluster headache is a relatively rare headache disorder, typically characterized by multiple daily, short-lasting attacks of excruciating, unilateral (peri-)orbital or temporal pain associated with autonomic symptoms and restlessness. To better understand the pathophysiology of cluster headache, we used RNA sequencing to identify differentially expressed genes and pathways in whole blood of patients with episodic (n = 19) or chronic (n = 20) cluster headache in comparison with headache-free controls (n = 20).

A genetic CLOCK variant associated with cluster headache causing increased mRNA levels

Cluster headache is characterized by recurrent unilateral headache attacks of severe intensity. One of the main features in a majority of patients is a striking rhythmicity of attacks. The CLOCK (Circadian Locomotor Output Cycles Kaput) gene encodes a transcription factor that serves as a basic driving force for circadian rhythm in humans and is therefore particularly interesting as a candidate gene for cluster headache.

Clinical Features of Cluster Headache Patients in Korea

Cluster headache (CH) is a rare underdiagnosed primary headache disorder with very severe unilateral pain and autonomic symptoms. Clinical characteristics of Korean patients with CH have not yet been reported. We analyzed the clinical features of CH patients from 11 university hospitals in Korea. Among a total of 200 patients with CH, only 1 patient had chronic CH. The average age of CH patients was 38.1 ± 8.9 years (range 19–60 years) and the average age of onset was 30.7 ± 10.3 years (range 10–57 years). The male-to-female ratio was 7:1 (2.9:1 among teen-onset and 11.7:1 among twenties-onset). Pain was very severe at 9.3 ± 1.0 on the visual analogue scale. The average duration of each attack was 100.6 ± 55.6 minutes and a bout of CH lasted 6.5 ± 4.5 weeks. Autonomic symptoms were present in 93.5% and restlessness or agitation was present in 43.5% of patients. Patients suffered 3.0 ± 3.5 (range 1–25) bouts over 7.3 ± 6.7 (range 1–30) years. Diurnal periodicity and season propensity were present in 68.5% and 44.0% of patients, respectively. There were no sex differences in associated symptoms or diurnal and seasonal periodicity. Korean CH patients had a high male-to-female ratio, relatively short bout duration, and low proportion of chronic CH, unlike CH patients in Western countries.

Improved surgical procedure using intraoperative navigation for the implantation of the SPG microstimulator in patients with chronic cluster headache

The ATI SPG microstimulator is designed to be fixed on the posterior maxilla, with the integrated lead extending into the pterygopalatine fossa to electrically stimulate the sphenopalatine ganglion (SPG) as a treatment for cluster headache. Preoperative surgical planning to ensure the placement of the microstimulator in close proximity (within 5 mm) to the SPG is critical for treatment efficacy. The aim of this study was to improve the surgical procedure by navigating the initial dissection prior to implantation using a passive optical navigation system and to match the post-operative CBCT images with the preoperative treatment plan to verify the accuracy of the intraoperative placement of the microstimulator.

In the face of pain there are no heroes

Most of the barriers preventing an appropriate care of CH sufferers may be overcome with a little organisational and cultural effort. The European Headache Alliance and the European Headache Federation have launched the Cluster Headache Day with the intention to solicit the Members of the European Parliaments’ help in promoting actions for improving the quality of life of CH patients.