磁共振波谱对创伤性脑损伤后活体脑组织神经生化代谢的即时、动态及客观分析(英文)

Magnetic resonance spectroscopy for real-time,dynamic and objective analysis of neurochemical metabolism following traumatic brain injury

背景:磁共振波谱分析(magneticresonancespectroscopy,MRS)为脑活体组织代谢物质无创检测技术,可实施长期动态监测,其实验与临床研究结果预示了其良好的应用前景。目的:回顾关于磁共振波谱分析原理及对创伤性脑损伤后磁共振波谱分析的实验和临床研究结果,明确创伤性脑损伤后脑组织继发性病理生理改变的神经生化机制。资料来源:应用计算机检索Medline1981-01/2003-10的相关文章,检索词“magneticresonancespectroscopy;braininjury;brainmetabolism,并限定文章语言种类为English。同时手工检索中国临床康复杂志2003-《》“磁共01/2004-03期间的相关文章,限定文章语言种类为中文,检索词振波谱”。资料选择:符合本条件的RCT基础与临床研究文章共33篇。选择关于磁共振波谱分析及创伤性脑损伤与磁共振波谱分析的文献,但不排除是否为盲法论证的文章。资料提炼:磁共振波谱分析可反映创伤性脑损伤后活体脑组织代谢物质的动态变化。脑白质代谢物质的变化可反映轴索损伤的情况,脑灰质代谢物质的变化可反映脑挫裂伤损伤的情况。伤后早期脑代谢物质变化主要表现为一致性降低,其降低程度与伤情严重性一致;伤后晚期或恢复期,脑代谢物质浓度逐渐升高,反映了脑组织的修复情况。检测到乳酸往往提示预后不良。

BACKGROUND:Magnetic resonance spectroscopy(MRS) is a non traumatic modality f or detecting the metabolic substances in the brain tissues and can be used for l ong term dynamic monitoring. Experimental and clinical studies have suggested t he great clinical potential of this technique. OBJECTIVE:To review the principles of MRS analysis and the results of relevant experimental and clinical studies on its use in post traumatic brain injury,th ereby to explore the neurochemical mechanism of secondary pathophysiological cha nges of the brain tissue following traumatic injury. DATA SOURCES:A computer based search of the Medline for relevant studies publ ished between January 1981 and October 2003 was performed using key words of “magnetic resonance spectroscopy;brain injury and brain metabolism',with language of the articles limited to English.Meanwhile a manual search of the print journa l Chinese Journal of Clinical Rehabilitation for such articles published in Chin ese language between January 2003 and March 2004 was also conducted with the same key words in Chinese. STUDY SELECTION:Totally 33 randomized controlled trial(RCT) basic research and clinical literatures satisfying the specified conditions were found.Articles of study on MRS,as well as on the relationship between MRS and traumatic brain inj ury were considered valid for inclusion for this review, all being original work without limitation of blind trial. DATA EXTRACTION:MRS defines the dynamic changes of cerebral metabolic substanc e following traumatic brain injury,and such changes in the white matter suggest the degree of neuraxon injury,while those in the gray matter indicate the state of brain laceration.The main changes of the metabolic substances in the early st age after injury were their uniform reduction that is consistent with the severi ty of trauma.The concentration of the metabolic substances gradually increases d uring the latter stages of the injury, reflecting the state of cerebral recovery .Detection of lactic acid often indicates poor prognosis.Changes of pH present d ifferent pictures in focal brain injury and diffuse axonal injury. DATA SYNTHESIS:MRS can detect cerebral neural physiochemical metabolic changes following traumatic injury in a real time,dynamic and objective manner for its capability in detecting super early brain injury and assessing the severity of brain trauma and post trauma recovery,and even in distinguishing reversible fr om irreversible injuries.MRS can be used for detecting not only cerebral metabol ic changes,but also changes of intracellular pH and Mg2+, to comprehensively re flect cerebral metabolic changes of a unit volume. In addition, the site for det ection can be selected at will on the basis of the MRS images. CONCLUSION:MRS can detect cerebral neural physiochemical metabolic changes aft er traumatic injury in real time,dynamic and objective manner.