3.0T磁共振扩散张量成像对兔心肌梗死后心室异质性重构的评估价值  

Evolution of Ventricular Remodeling Heterogeneity After Myocardial Infarction Using 3. 0 T Magnetic Resonance Diffusion Tensor Imaging

作　　者：喻思思[1] 殷亮[1] 任海波[1] 唐雪培 俞瑶涵 熊发奎 龚良庚[1] YU Sisi YIN Liang REN Haibo et al(Department of Radiology, the Second Affilated Hospital of Nanchang University, Nanchang ,Jiangxi Province 330006, P. R. Chin)

机构地区：[1]南昌大学第二附属医院放射科,330006

出　　处：《临床放射学杂志》2016年第11期1771-1774,共4页Journal of Clinical Radiology

基　　金：国家自然科学基金项目(编号:81360216;81660284);江西省自然科学基金重大项目(编号:2016ACB2013)

摘　　要：目的运用3.0 T磁共振扩散张量成像(MR-DTI)对兔心肌梗死(MI)后梗死区(CIZ)、边缘区(PIZ)及非梗死区(NIZ)的心肌微观结构进行检测,探索不同区域纤维重构的异质性。方法采用成年雄性兔分为正常组、假手术组及MI组。结扎冠状动脉左室支,建立兔MI模型。对离体心脏标本行3.0 T MR-DTI扫描,测量不同区域的各向异性分数(FA)值和平均扩散系数(MD)值,并行纤维素示踪成像和重建主本征矢量图,比较不同区域重构的差异。结果 MI后从CIZ向PIZ延展,再到NIZ代偿性重构,平均FA值呈上升趋势,平均MD值呈下降趋势。分别对MI后1 w、2 w、4 w、8 w及16 w组的三个区域进行两两比较,显示在不同时间点三个区域之间的FA值均有统计学差异。MD值在术后1 w组的CIZ与PIZ、PIZ与NIZ间,在术后2 w组三个区域之间,以及在术后8 w组的PIZ与NIZ间两两比较无统计学差异,其余比较均有差异。结论 MI从CIZ向PIZ延展,再到NIZ,重构程度呈渐变性,以CIZ最明显。FA值评估重构的异质性可能较MD值更为稳定可靠。Objective Using 3.0 T magnetic resonance diffusion tensor imaging （MR-DTI） to detect cardiac muscle fibers structure of the core-infarction zone （CIZ） , peri-infarction zone （PIZ） and non-infarction zone （NIZ） after myocardial infarction （ MI）, so as to explore the heterogeneity of ventricular remodeling in different areas. Methods We chose adult male rabbits; divided into normal group, sham operation group and MI group. We established rabbit-MI models by ligating the left ventricular branch of the coronary artery. The heart types were scanned in vitro DTI and images post-processed by measuring the fractional anisotropy （FA） values and mean diffusion coefficient （MD） values, and proceeding to diffusion tensor tractography and reconstruction primary eigenvector maps in different areas. We compared the difference of remodeling in CIZ, PIZ and NIZ by DTI. Results After MI, from the CIZ extending to the PIZ, and compensatory remodeling of the NIZ, the average FA values were on the rise, while the average MD values were on the decline. We made pairwise comparison analysis in different areas according to the different groups respectively. In the 1 w, 2 w, 4 w, 8 w and 16 w, the FA values all were statistically significant between each zone. In the MD analysis, the results showed the MD in these pairwise areas, including the CIZ with PIZ and PIZ with NIZ in the 1 w group, three pairwise areas in the 2 w group, and PIZ with NIZ in the 8 w group, had no statistical difference, while the remaining pairwise comparison had statistical difference. Conclusion From the CIZ extending to PIZ, and compensatory remodeling of the NIZ, the degree of remodeling gradually changed, with the CIZ the being most obvious. Moreover, the FA in assessing remodeling heterogeneity might be more stable and reliable compared with the MD.

关 键 词：磁共振 扩散张量成像 心肌梗死 重构 

分 类 号：R445.2[医药卫生—影像医学与核医学]