新生猪缺氧缺血性脑病扩散峰度成像的时间进程变化  

Time Course Changes of Diffusion Kurtosis Imaging of Hypoxic-ischemic Encephalopathy in Newborn Swine

作　　者：何晓宁 肖娟 田娟[1] 吴鹏 韩雨璇 杨超[1] HE Xiaoning;XIAO Juan;TIAN Juan;WU Peng;HAN Yuxuan;YANG Chao(Department of Radiology,the Second Hospital of Dalian Medical University,Dalian 116000,China)

机构地区：[1]大连医科大学附属第二医院放射科

出　　处：《中国医学影像学杂志》2020年第1期1-5,共5页Chinese Journal of Medical Imaging

基　　金：国家自然科学基金（81771663）;辽宁省自然科学基金（20170540237）

摘　　要：目的分析新生猪缺氧缺血性脑病扩散峰度成像(DKI)相关参数随时间变化规律,并与扩散张量成像(DTI)相关参数对比。材料与方法选取出生3~5 d内的健康约克种猪20只,分为实验组15只和对照组5只。实验组结扎双侧颈总动脉后放入氧浓度为4%的乏氧箱内,乏氧30 min。对照组仅行分离双侧颈总动脉的假手术。实验组和对照组在模型建立后3、6、9、12、16、24 h分别进行DKI扫描,扫描完成后,实验组和对照组各选3只猪取脑行病理学检查。结果实验组猪缺氧缺血发生后,病变处DKI相关参数平均扩散峰度(MK)、径向扩散峰度(Kr)、轴向扩散峰度(Ka)较对照组逐渐升高,差异有统计学意义(P<0.05);DTI相关参数平均扩散系数(MD)、垂直扩散张量(Dr)、轴向扩散张量(Da)逐渐降低,差异有统计学意义(P<0.05)。DKI相关参数值变化率大于DTI相关参数值变化率,且平行于轴突方向的变化率均大于垂直于轴突方向的变化率(Ka、Da、Kr及Dr的平均变化率分别为119.75%、55.54%、93.32%、50.51%)。实验组病理结果显示神经元水肿,大量炎症细胞浸润,局部可见坏死。结论与DTI相关参数相比,DKI能够更敏感地评价缺氧缺血性脑病脑组织微结构的变化。Purpose To analyze the time change rule of related parameters of diffusion kurtosis imaging(DKI) of hypoxic-ischemic encephalopathy(HIE) in neonatal swine along with time, and to compare with related parameters of diffusion tensor imaging(DTI). Materials and Methods Twenty healthy York swine within 3 to 5 days after birth were selected, and divided into 15 in experiment group and 5 in control group. In experiment group, bilateral common carotid arteries were ligated and put into hypoxic chamber with 4% FiO for 30 minutes. In control group, only pseudo-operation was performed on bilateral carotid arteries. 3, 6, 9, 12, 16 and 24 hours after setting up model, DKI scanning was performed in experiment group and control group respectively. After scanning, select three swine from experiment group and control group respectively for pathological examinations. Results After occurrence of hypoxia and ischemia in swine in experiment group, related DKI parameters including mean diffusion kurtosis(MK), radial kurtosis(Kr) and axial kurtosis(Ka) on lesions were gradually enhanced compared with those in control group, with statistical significance(P<0.05). Related DTI parameters including mean diffusion coefficient(MD), vertical diffusion tensor(Dr) and axial diffusion tensor(Da) gradually decreased and the difference, with statistical significance(P<0.05). Change rate of related DKI parameters was higher than those of related DTI parameters. Meanwhile, change rate parallel to axon direction was all greater than that vertical to that of axon direction(mean change rate of Ka, Da, Kr and Dr was 119.75%, 55.54%, 93.32% and 50.51%, respectively). Pathological results in experiment group indicated neuronal edema, a great amount of inflammatory cells infiltration and local necrosis. Conclusion Compared with related DTI parameters, DKI can evaluate changes of cerebral micro-structure in hypoxicischemic encephalopathy.

关 键 词：缺氧缺血 脑 磁共振成像 扩散峰度成像 扩散张量成像 病理学 外科 疾病模型 动物 猪 

分 类 号：R445.2[医药卫生—影像医学与核医学] R-33[医药卫生—诊断学]