1 Department of Neurology, Tri-Service General Hospital, National Defense Medical Center, Taiwan.
2 Brain Research Center, National Yang-Ming University, Taiwan.
Cephalalgia. 2018 Apr;38(5):970-983. doi: 10.1177/0333102417716932. Epub 2017 Jul 5.
Background Cluster headache is a disorder characterized by intermittent, severe unilateral head pain accompanied by cranial autonomic symptoms. Most cases of CH are episodic, manifesting as "in-bout" periods of frequent headache separated by month-to-year-long "out-of-bout" periods of remission. Previous imaging studies have implicated the hypothalamus and pain matrix in the pathogenesis of episodic CH. However, the pathophysiology driving the transition between in- and out-of-bout periods remains unclear. Methods The present study provides a narrative review of previous neuroimaging studies on the pathophysiology of episodic CH, addressing alterations in brain structures, metabolism, and structural and functional connectivity occurring between bout periods. Results Although the precise brain structures responsible for episodic CH are unknown, major roles are indicated for the posterior hypothalamus (especially in acute attacks), the pain neuromatrix with an emphasis on central descending pain modulation, and non-traditional pain processing networks including the occipital, cerebellar, and salience networks. These areas are potentially related to dynamic transitioning between in- and out-of-bout periods. Conclusion Recent progress in magnetic resonance imaging of episodic CH has provided additional insights into dynamic bout-associated structural and functional connectivity changes in the brain, especially in non-traditional pain processing network areas. These areas warrant future investigations as targets for neuromodulation in patients with CH.
背景 丛集性头痛是一种以间歇性、剧烈单侧头痛伴有颅自主症状为特征的疾病。大多数丛集性头痛为发作性，表现为频繁头痛的“发作期”，与月至年的“缓解期”交替出现。先前的影像学研究表明，下丘脑和疼痛矩阵在发作性丛集性头痛的发病机制中起作用。然而，导致发作期和缓解期之间转变的病理生理学机制仍不清楚。
方法 本研究对发作性丛集性头痛的神经影像学研究进行了叙述性综述，探讨了发作期之间脑结构、代谢以及结构和功能连接的改变。
结果 尽管负责发作性丛集性头痛的确切脑结构尚不清楚，但后下丘脑（特别是在急性发作期间）、疼痛神经矩阵（强调中枢下行疼痛调节）和非传统疼痛处理网络（包括枕叶、小脑和突显网络）的重要作用得到了强调。这些区域可能与发作期和缓解期之间的动态转换有关。
结论 发作性丛集性头痛的磁共振成像的最新进展提供了关于大脑中与发作相关的结构和功能连接变化的更多见解，特别是在非传统疼痛处理网络区域。这些区域值得进一步研究，作为丛集性头痛患者神经调节的靶点。
