慢性疼痛患者基于静息态功能性核磁共振的研究进展

Resting state functional magnetic resonance imaging of brain structures in chronic pain syndromes

背景近几年的MRI结构像研究提示，持续的慢性疼痛可导致大脑结构的改变。国内外已有研究证实，慢性疼痛患者脑内主要负责疼痛调控脑区的灰质出现损伤或减少，而大脑结构的改变在慢性疼痛得到充分治疗后常能够逆转。目的综述几类常见慢性疼痛综合征诱发的大脑结构改变，提高研究者对慢性疼痛过程中发生皮质重塑的理解。内容以往研究发现慢性背痛患者双侧前额叶皮质区背外侧前额叶皮质灰质减少，幻肢痛患者外侧丘脑的灰质减少，并且丘脑灰质减少程度与截肢时间呈正相关，而头面部疼痛等慢性疼痛综合征可导致疼痛功能网络中多个脑区的灰质出现减少。趋向这类基于大脑MRI结构像的研究，加深了研究者对慢性疼痛综合征是一类进展性疾病的认识。慢性疼痛过程中发生的皮质重塑机制仍有待进一步研究，这将对慢性疼痛的治疗有重要的临床指导意义。

Background Magnetic resonance imaging studies demonstrate that damage and shrinkage of gray matter exist in pain-related brain areas in patients suffered from chronic pain, and is dynamic and reversible during treatment. Objective To review brain areas showing structural alterations in patients with chronic pain and to improve the understanding of cortical reorganization in chronic pain. Content There is a reciprocal relationship between chronic pain and malfunction of brain areas. Patients with chronic back pain exhibits a decreased gray matter in the dorsolateral prefrontal cortices （DLPFCs） bilaterally. Another study demonstrated that amputees showed a gray matter reduction in the posterolateral thalamus. In addition,a positive correlation between thalamic gray matter loss and time since amputation was found. Chronic pain syndromes such as headache and facial pain can induce reduced gray matter in multiple areas in the pain matrix. This article reviews MRI studies in patients with chronic back pain, phantom limb pain, head and facial pain, primary fibromyalgia, irritable bowel syndrome, complex regional pain syndrome. Trend As the reduction of gray matter exacerbates as pain syndromes persist, monitoring the gray matter can provide a means to evaluate the therapeutic efficacy of a treatment for chronic pain syndrome.