兔坐骨神经急性挤压伤模型的建立及扩散峰度成像的b值优选  

Establishment of peripheral nerve acute crush injury animal model and b value optimization of diffusion kurtosis imaging

作　　者：梁晓韵 万齐[2] 余煜栋 彭玉 陈智杰[2] 李新春[2] LIANG Xiaoyun;WAN Qi;YU Yudong;PENG Yu;CHEN Zhijie;LI Xinchun(Department of Radiology,Affiliated Hospital of Traditional Chinese Medicine of Guangzhou Medical University,Guangzhou 510000,China;Department of Radiology,The First Affiliated Hospital of Guangzhou Medical University,Guangzhou 510120,China)

机构地区：[1]广州医科大学附属中医医院放射科,广东广州510000 [2]广州医科大学附属第一医院放射科,广东广州510120

出　　处：《分子影像学杂志》2021年第4期589-593,共5页Journal of Molecular Imaging

基　　金：国家自然科学基金(81171800);广东省科技计划项目(2016A020215168)。

摘　　要：目的制作适合MRI监测的兔坐骨神经挤压伤模型,并对扩散峰度成像(DKI)b值的选择进行探讨。方法选用健康新西兰大白兔27只,使用宽度约8 mm的自制扁嘴钳建立坐骨神经损伤模型,选取右后肢为手术侧,左侧为假手术侧,于术前及1 d、3 d、1周、2周、4周及8周各时间点行DKI扫描,b值分别为0、750、1500 s/mm^(2)及0、1000、2000 s/mm^(2)。于各时间点随机取2只兔子进行病理检查。结果DKI1500与DKI2000各参数值具有相似的变化趋势。FA1500与FA2000均在第1天降至最低,之后在3 d~8周持续回升,各时间点组间差异均有统计学意义(P<0.05);在第1天均明显下降,此后开始缓慢、曲折上升的趋势,双侧MK1500值在术后第2周(P=0.022)、第4周(P=0.018)、第6周(P=0.016)及第8周(P=0.016)差异有统计学意义。而MK2000仅在第4周组间差异有统计学意义(P=0.002)。RK值及AK值在绝大多数时间点差异无统计学意义。结论使用扁嘴钳钳夹兔坐骨神经中段制作损伤与修复模型,可方便使用MRI对损伤段神经进行直接监测与定量测量;DKI周围神经成像最大b值取1500 s/mm^(2)可能较2000 s/mm^(2)更为合适。Objective To establish a rabbit sciatic nerve crush injury model suitable for MRI monitoring,and discuss the selection of b value of diffusion kurtosis imaging(DKI).Methods Twenty-seven healthy New Zealand white rabbits were selected.The sciatic nerve injury model was established with self-made flat forceps with a width of about 8mm.The right posterior limb was selected as the injury side and the left was the sham surgical side.DKI was performed before and 1 d,3 d,1 week,2 weeks,4 weeks and 8 weeks after injury,with b values of 0,750,1500 s/mm2 and 0,1000,2000 s/mm2,respectively.Two rabbits were randomly selected at each time point for pathological examination.Results The parameters of DKI1500 and DKI2000 showed similar trends.Both FA1500 and FA2000 decreased to the lowest level on the first day and then continued to increase at 3-8 weeks,with statistically significant differences among groups at each time point(P<0.05).The MK1500 of both sides was significantly decreased on the first day,and then slowly increased.The differences in the MK1500 of both sides at the second week(P=0.022),the fourth week(P=0.018),the sixth week(P=0.016)and the eighth week(P=0.016)after injury were significant.The difference of MK2000 between groups was significant only at the fourth week(P=0.002).There was no significant difference between Rk and AK at most time points.Conclusion Using flat forceps to clamp the middle segment of the rabbit sciatic nerve to make the injury model can facilitate the direct monitoring and quantitative measurement of the injured nerve by MRI.A maximum b value of 1500 s/mm2 for DKI imaging may be more suitable than 2000 s/mm2.

关 键 词：周围神经 动物模型 磁共振成像 扩散峰度成像 

分 类 号：R445.2[医药卫生—影像医学与核医学] R651.3[医药卫生—诊断学] R-332[医药卫生—临床医学]