CAJ | 학술논문

目的：利用高场强MRI序列描绘早期脑卒中血脑屏障(BBB)损伤随时间变化的影像学特征，并结合频谱中脑代谢物的变化情况，为早期溶栓治疗提供直观和个体化的影像学指导信息。材料与方法健康SD大鼠20只，采用栓线法制备大鼠大脑中动脉闭塞(MCAO)模型，在Angilent 7.0 T动物MR扫描仪上行常规扫描(T1WI、T2WI、DWI)，静脉注射MRI对比剂Gd-DTPA后行T1WI增强扫描，并利用MR频谱(1H MRS)技术测量超早期各时间段内病灶区的脑代谢物浓度变化，并用LCModel软件定量出病变区特定代谢物的绝对浓度。结果各组MCAO大鼠，大脑中动脉闭塞10 min后，DWI均能在大脑中动脉供血相应纹状体区及顶叶皮层区显示出异常的高信号，其中1.5 h组MCAO大鼠，大脑中动脉闭塞1.5 h再灌注30 min后，增强T1WI扫描出现脑室系统(第三脑室，侧脑室等)明显高信号改变；而2.0 h组MCAO大鼠再灌注30 min后局部脑实质内可出现明显T1高信号改变。未灌注组MCAO大鼠频谱发现，大脑中动脉闭塞1 h(频谱第一时间段)病变缺血区较对侧正常区Lac峰明显增高，NAA峰明显下降；谷氨酸和牛磺酸的绝对浓度于2 h内逐渐上升至峰值后，3 h段开始明显下降。结论利用MRI对比剂Gd-DTPA的T1WI成像方法可描绘出急性缺血性脑卒中BBB损伤随时间的变化，并采用MR频谱技术正确量化同时期相关脑代谢物的变化。总之，这些相关评估将对溶栓治疗提供客观和个体化的影像学信息。
목적：이용고장강MRI서렬묘회조기뇌졸중혈뇌병장(BBB)손상수시간변화적영상학특정，병결합빈보중뇌대사물적변화정황，위조기용전치료제공직관화개체화적영상학지도신식。재료여방법건강SD대서20지，채용전선법제비대서대뇌중동맥폐새(MCAO)모형，재Angilent 7.0 T동물MR소묘의상행상규소묘(T1WI、T2WI、DWI)，정맥주사MRI대비제Gd-DTPA후행T1WI증강소묘，병이용MR빈보(1H MRS)기술측량초조기각시간단내병조구적뇌대사물농도변화，병용LCModel연건정량출병변구특정대사물적절대농도。결과각조MCAO대서，대뇌중동맥폐새10 min후，DWI균능재대뇌중동맥공혈상응문상체구급정협피층구현시출이상적고신호，기중1.5 h조MCAO대서，대뇌중동맥폐새1.5 h재관주30 min후，증강T1WI소묘출현뇌실계통(제삼뇌실，측뇌실등)명현고신호개변；이2.0 h조MCAO대서재관주30 min후국부뇌실질내가출현명현T1고신호개변。미관주조MCAO대서빈보발현，대뇌중동맥폐새1 h(빈보제일시간단)병변결혈구교대측정상구Lac봉명현증고，NAA봉명현하강；곡안산화우광산적절대농도우2 h내축점상승지봉치후，3 h단개시명현하강。결론이용MRI대비제Gd-DTPA적T1WI성상방법가묘회출급성결혈성뇌졸중BBB손상수시간적변화，병채용MR빈보기술정학양화동시기상관뇌대사물적변화。총지，저사상관평고장대용전치료제공객관화개체화적영상학신식。
Objectives: Blood brain barrier (BBB) damage that occurs within the thrombolytic time window is increasingly appreciated to negatively impact the safety and efifcacy proifles of thrombolytic therapy for ischemic stroke. Here, we investigated the topographical distribution of BBB damage and its association with tissue injury within the first 3 h after ischemia onset and the related roles of neurochemical metabolites profiles in this process.Materials and Methods: Here, using contrast-enhanced magnetic resonance imaging (CE-MRI) and single-voxel localization technique, we assessed BBB disruption onset time and related neurochemical alteration in rats following middle cerebral artery occlusion (MCAO) for 1, 2 and 3 h. Proton metabolites were quantified using LCModel software.Results: In the 1.5 h MCAO group, after 0.5 h reperfusion, abnormal hyperintense signals were seen in both lateral ventricles and the central canal in the CE-T1WI image, and expanded with time to other MCA regions, including the ventromedial striatum in the 2 h MCAO group, after 0.5 h reperfusion. The concentrations of glutamate+glutamine (Glu+Gln), taurine (Tau) and creatine+phosphocreatine (Cr+PCr) increased gradually within the ifrst 2 h (P<0.05, respectively), and then decreased (P<0.05, respectively) in the following 1 h after ischemia onset, as evaluated by1H-MRS. Other metabolites observed in this study did not show signiifcant changes over the time.Conclusions: Our ifndings suggest Tau, Glu+Gln and Cr+PCr levels may be useful biomarkers to detect BBB damage and relevant events in the ischemic cascade, and predict onset time of BBB disruption to improve the accuracy of acute stroke diagnosis and determine the safety and efifcacy of early thrombolytic therapy.