犬急性心肌梗死磁共振心肌灌注及电影成像实验研究  

Myocardial First-pass Perfusion MRI and Cine MR of Acute Myocardial Infarction: An Experimental Study in Dogs

作　　者：江利[1] 冯敢生[2] 孔祥泉[2] 吴汉平[2] 肖学宏[3] 梁惠民[2] 杨建勇[4] 

机构地区：[1]华中科技大学同济医学院附属协和医院放射科,武汉430022 [2]武汉华中科技大学同济医学院附属协和医院放射科,430022 [3]广东省中山市人民医院放射科 [4]广州中山医科大学附属第一医院放射科,510080

出　　处：《临床放射学杂志》2002年第6期470-474,共5页Journal of Clinical Radiology

摘　　要：目的　采用MR快速序列研究急性心肌梗死的首过灌注特点及心功能改变。材料与方法　犬心肌梗死模型 9只 ,均进行T1WI磁化准备梯度回波序列 (TurboFLASH)首过灌注扫描及MR电影成像 (cine MR) ,完成检查后处死 ,分析心肌首过灌注特点及局部心功能变化 ,并与病理检查比较。结果　首过灌注时梗死心肌表现为灌注缺损 ,信号强度 时间曲线上升延缓 ,曲线斜率和峰值信号强度分别为 0 .0 2 5± 0 .0 2 0和 0 .84± 0 .2 7,较正常心肌(0 .13± 0 .0 80和 2 .0 2± 0 .99,P <0 .0 0 0 1)明显下降 ,峰值时间和曲线上升时间分别为 37.78± 11.90s和 32 .70±14 .0 9s,较正常心肌 (17.14± 6 .0 6s和 14 .2 8± 5 .14s,P <0 .0 0 0 1)明显延长。延迟期正常心肌信号强度下降 ,而梗死心肌仍呈上升趋势。首过灌注中灌注缺损面积与TTC染色一致。梗死节段室壁运动及室壁厚度异常。结论　MR首过灌注成像可反映病变心肌组织血流灌注信息 ,cine MR能测定节段室壁功能。结合首过灌注和心功能分析 ,可对梗死心肌在形态学和功能学两方面进行定性、定量分析 。Objective To study myocardial first pass perfusion features and functional changes in acute myocardial infarction by using fast MRI scanning sequence.Materials and Methods Turbo FLASH first pass and cine MRI were performed in nine canine models of acute myocardial infarction. The dogs were sacrificed after the exam. The first pass perfusion features and the functional changes of the local myocardium were analyzed. The findings were compared with the pathological results.Results During the first pass perfusion, the infarcted myocardium showed perfusion defect, and the signal intensity time curve was going up slowly. After the signal intensity peak the curve became a plateau. The curve's upslope and the peak signal intensity were 0.025± 0.020 and 0.84±0.27 for the infarcted myocardium, while 0.130±0.080 and 2.02±0.99 for the normal myocardium. Significant difference existed between the infarcted and normal myocardium (P<0.0001). The peak time and the upslope time were 37.78±11.90s and 32.70±14.09s for the infarcted myocardium, both were much longer than that for normal myocardium (17.14±6.06s and 14.28±5.14s), with P<0.0001. During the delayed phase, the signal intensity of normal myocardium was declined, but the signal intensity of infarcted myocardium was still going up. The perfusion defect area was coincident with TTC stain results. The regional movement and the wall thickness of the infarcted segments were abnormal.Conclusion The first-pass perfusion MR imaging can reflect the infarcted myocardial blood flow, while the cine MR can assess regional ventricular wall function. A combination of the first pass perfusion MR imaging with the analysis of myocardial function is useful for the qualitative and quantitative analysis of the infarcted myocardium both morphologically and functionally, which is very helpful in assessing the viability of the myocardium.

关 键 词：急性心肌梗死 磁共振心肌灌注 电影成像 实验研究 

分 类 号：R445.2[医药卫生—影像医学与核医学]