Deep brain stimulation modulates hypothalamic-brainstem fibers in cluster headache: case report

Ten-Year Durability of Hypothalamic Deep Brain Stimulation in Treatment of Chronic Cluster Headaches: A Case Report and Literature Review

Chronic cluster headache (CCH) is a debilitating primary headache that causes excruciating pain without remission. Various medical and surgical treatments have been implemented over the years, yet many provide only short-term relief. Deep brain stimulation (DBS) is an emerging treatment alternative that has been shown to dramatically reduce the intensity and frequency of headache attacks. However, reports of greater than 10-year outcomes after DBS for CCH are scant. Here, we report the durability of DBS in the posterior inferior hypothalamus after 10 years on a patient with CCH. Our patient experienced an 82% decrease in the frequency of headaches after DBS, which was maintained for over 10 years. The side effects observed included depression, irritability, anxiety, and dizziness, which were alleviated by changing programming settings. In the context of current literature, DBS shows promise for long-term relief of cluster headaches when other treatments fail.

Primary headache disorders: From pathophysiology to neurostimulation therapies

Primary headache disorders including migraine, cluster headache, and tension-type headache are among the most common disabling diseases worldwide. The unclear pathogenesis of primary headache disorders has led to high rates of misdiagnosis and limited available treatment options. In this review, we have summarized the pathophysiological factors for a better understanding of primary headache disorders. Advances in functional neuroimaging, genetics, neurophysiology have indicated that cortical hyperexcitability, regional brain dysfunction, central sensitization and neuroplasticity changes play vital roles in the development of primary headache disorders. Moreover, we have also discussed a series of neurostimulation approaches with their stimulation mechanism, safety and efficacy for prevention and treatment of primary headache disorders. Noninvasive or implantable neurostimulation techniques show great promise for treating refractory primary headache disorders.

Secondary cluster headache due to a contralateral demyelinating periaqueductal gray matter lesion

OBJECTIVES/BACKGROUND

Tension-type headache and migraine without aura are the most common primary headaches occurring in people with demyelinating diseases, whereas cluster headache (CH) can be considered exceptional. The location of demyelinating lesions could be strategic in these cases, involving areas interacting with the trigeminovascular system.

METHODS AND RESULTS

We report a case of a 54-year-old woman with right-sided CH as the initial manifestation of multiple sclerosis and showing a left dorsal brainstem lesion on magnetic resonance imaging, in the region of the dorsal longitudinal fasciculus (DLF).

CONCLUSION

Our case seems to suggest a possible role of the DLF in the process that leads to CH attacks. Because neuroimaging clearly showed a lesion contralateral to CH pain, we hypothesize that some fibers from periaqueductal gray matter project to the contralateral side, besides the known ipsilateral connections.

Mapping autonomic, mood, and cognitive effects of hypothalamic region deep brain stimulation

Due to its involvement in a wide variety of cardiovascular, metabolic, and behavioral functions, the hypothalamus constitutes a potential target for neuromodulation in a number of treatment-refractory conditions. The precise neural substrates and circuitry subserving these responses, however, are poorly characterized to date. We sought to retrospectively explore the acute sequalae of hypothalamic region deep brain stimulation and characterize their neuroanatomical correlates. To this end we studied at multiple international centers 58 patients (mean age: 68.5 ± 7.9 years, 26 females) suffering from mild Alzheimer's disease who underwent stimulation of the fornix region between 2007 and 2019. We catalogued the diverse spectrum of acutely induced clinical responses during electrical stimulation and interrogated their neural substrates using volume of tissue activated modelling, voxel-wise mapping, and supervised machine learning techniques. In total 627 acute clinical responses to stimulation - including tachycardia, hypertension, flushing, sweating, warmth, coldness, nausea, phosphenes, and fear - were recorded and catalogued across patients using standard descriptive methods. The most common manifestations during hypothalamic region stimulation were tachycardia (30.9%) and warmth (24.6%) followed by flushing (9.1%) and hypertension (6.9%). Voxel-wise mapping identified distinct, locally separable clusters for all sequelae that could be mapped to specific hypothalamic and extrahypothalamic gray- and white-matter structures. K-nearest neighbor classification further validated the clinico-anatomical correlates emphasizing the functional importance of identified neural substrates with area under the receiving operating characteristic curves (AUROC) between 0.67 - 0.91. Overall, we were able to localize acute effects of hypothalamic region stimulation to distinct tracts and nuclei within the hypothalamus and the wider diencephalon providing clinico-anatomical insights that may help to guide future neuromodulation work.

Understanding Cluster Headache Using Magnetic Resonance Imaging

Cluster headache is an excruciating pain syndrome characterized by unilateral head pain attacks, lasting between 15 and 180 min, accompanied by marked ipsilateral cranial autonomic symptoms, such as lacrimation and conjunctival injection. Despite important insights provided by neuroimaging studies and deep brain stimulation findings, the pathophysiology of cluster headache and its pathways of chronicization are still elusive. In this mini-review, we will provide an overview of the functional and structural neuroimaging studies in episodic and chronic cluster headache conditions conducted to clarify the underlying pathophysiology.