Neoimaging Research Unit, Division of Neuroscience and Neurology Unit, IRCCS San Raffaele Scientific Institute, Milan, Italy.
Danish Headache Center, Department of Neurology, Rigshospitalet Glostrup, Faculty of Medical and Health Sciences, University of Copenhagen, Copenhagen, Denmark.
Curr Opin Neurol. 2022 Jun 1;35(3):328-335. doi: 10.1097/WCO.0000000000001060.
The underlying mechanisms of migraine are complex and heterogenous. Advances in neuroimaging techniques during the past few decades have contributed to our understanding of migraine pathophysiology. Brain function in migraine patients has been widely explored using functional MRI (fMRI). This review will highlight the major fMRI findings that characterize the different phases of migraine.
The migraine attack starts with hypothalamic hyperexcitability and early reorganization of the common ascending pain and central trigeminovascular pathways. Moreover, the visual cortex becomes hyperexcitable during the aura phase. During the headache phase, further disruptions of the pontine, thalamic, sensorimotor and visual networks occur, although the hypothalamic activity and connectivity normalizes. The visual cortex remains hyperexcitable during the postdromal phase. Asymptomatic migraine patients can also experience functional alternations of pain and visual processing brain areas. At present, the heterogeneity of the asymptomatic phase and fMRI findings make it difficult to find common denominator.
fMRI studies have captured functional brain changes associated with migraine phases, leading to an improvement of our understanding of migraine pathophysiology. Further MRI studies are needed to disclose whether the migraine attack is triggered by intrinsic brain dysfunction or external factors.
目的综述：偏头痛的发病机制复杂且存在异质性。过去几十年中神经影像学技术的进步促进了我们对偏头痛病理生理学的理解。功能性磁共振成像（fMRI）广泛用于研究偏头痛患者的大脑功能。本文将重点介绍偏头痛不同阶段的主要 fMRI 发现。
最近发现：偏头痛发作始于下丘脑活动亢进和常见上行疼痛及中枢三叉血管通路的早期重组。此外，在先兆期视觉皮层变得过度兴奋。在头痛期，尽管下丘脑活动和连通性恢复正常，但桥脑、丘脑、感觉运动和视觉网络进一步受到干扰。在后续期，视觉皮层仍然过度兴奋。无症状偏头痛患者也可能经历疼痛和视觉处理脑区的功能改变。目前，无症状期的异质性和 fMRI 结果使得很难找到共同的特征。
总结：fMRI 研究捕捉到与偏头痛各阶段相关的大脑功能变化，从而提高了我们对偏头痛病理生理学的理解。需要进一步的 MRI 研究来揭示偏头痛发作是由内在的大脑功能障碍还是外部因素引发的。
