目的 观察大鼠癫痫模型分析磁共振扩散成像特征与病理改变的关系,为深入分析磁共振扩散成像特征应用价值提供数据支撑。方法 将80只Wistar大鼠随机分为2组,空白对照组正常饲养,癫痫模型组以海仁酸注射法制备癫痫模型,测定各个脑区的平均峰度(MK)值、各向平均扩散率(MD)值、部分各向异性(FA)值、真性水分子扩散系数(D)、微循环灌注系数(D*)和灌注分数(f),对比分析其磁共振扩散成像参数与脑组织病理改变及神经元凋亡率的相关性。统计分析,计量资料先行正态分布及方差齐性检验,符合正态分布,组间比较行独立样本t检验；多个时间点的组间比较属于重复测量数据,行重复测量的方差分析及事后LSD、SNK检验；非正态分布,组间比较行Mann-Whitney U检验。相关性分析行Spearman相关(秩相关)及Pearson相关(简单线性相关)。结果 癫痫模型组海马区、丘脑及颞叶白质的MK值高于对照组,D值和f值低于对照组；组间差异有统计学意义(P＜0.05)。癫痫模型组致病后3d、1、3、5周的神经元凋亡率均高于空白对照组,差异有统计学意义(P＜0.05)。癫痫大鼠海马区、丘脑及颞叶白质的MK值和病理严重程度(ρ=0.665-0.778)、神经元凋亡率(r=0.675-0.705)呈正相关性,D值及f值与与病理严重程度(ρ=0.454-0.701)、神经元凋亡率(r=0.554-0.714)呈负相关性(P均<0.001)。结论 磁共振扩散成像能较为准确的反应癫痫患者脑组织病理变化,对其临床诊断和病情评估可能存在重要价值。

Objective: To observe the rat epilepsy model and analyze the relationship between diffusion imaging magnetic resonance characteristics and pathological changes, so as to provide data support for in-depth analysis of the application value of diffusion imaging magnetic resonance characteristics. Methods: 80 Wistar rats were randomly divided into two groups. The blank control group was fed normally. The epilepsy model group was prepared with kainic acid injection to prepare the epilepsy model, and the average kurtosis (MK) value and average diffusion rate of each brain area were measured ( MD) value, partial anisotropy (FA) value, true water molecule diffusion coefficient (D), microcirculation perfusion coefficient (D*) and perfusion fraction (f), compare and analyze its magnetic resonance diffusion imaging parameters and brain tissue pathological changes And the correlation of neuronal apoptosis rate. In statistical analysis, normal distribution and variance homogeneity test were conducted for measurement data, and independent sample t test was used for inter group comparison; multiple time points of inter group comparison belonged to repeated measurement data, and repeated measurement analysis of variance and post LSD, SNK test were performed; for non-normal distribution, Mann Whitney was used for inter group comparison U test. Spearman correlation (rank correlation) and Pearson correlation (simple linear correlation) were used for correlation analysis. Results: The MK values of hippocampus, thalamus and temporal lobe white matter in the epilepsy model group were higher than those in the control group, while D and F values were lower than those in the control group. The difference between groups was statistically significant (P < 0.05). The apoptosis rate of neurons in the epilepsy model group was higher than that in the blank control group at 3d, 1, 3 and 5 weeks after the disease was caused, and the difference was statistically significant (P < 0.05). The MK values of hippocampal, thalamus and temporal white matter in epileptic rats were positively correlated with pathological severity (ρ=0.665-0.778) and neuronal apoptosis rate (r=0.675-0.705), while D and F values were negatively correlated with pathological severity (ρ=0.454-0.701) and neuronal apoptosis rate (r= 0.554-0.714) (all P <0.001). Conclusion: Diffusion magnetic resonance imaging can more accurately reflect the pathological changes of brain tissue in patients with epilepsy, and may have important value in clinical diagnosis and disease evaluation.