3.0T MR膝部周围神经扩散张量成像参数的优选  

The optimization of DTI parameters of 3.0T MR for peripheral nerves of knees

作　　者：张付龙[1] 张敏凤[1] 杨哲 胡潇方[1] 刘胜全[1] 闫呈新[1] 朱建忠[1] ZHANG Fulong;ZHANG Minfeng;YANG Zhe;HU Xiaofang;LIU Shengquan;YAN Chengxin;ZHU Jianzhong(Department of Radiology ,the Affiliated Hospital of Taishan Medical College,Tai 'an 271000,China)

机构地区：[1]泰山医学院附属医院影像科,山东泰安271000

出　　处：《实用放射学杂志》2019年第2期290-293,共4页Journal of Practical Radiology

摘　　要：目的探讨3.0T MR正常膝部周围神经DTI合适的3个关键成像参数。方法应用3.0T MR对32名健康志愿者膝部分3次行实验性DTI扫描(层间距均为0 mm);第1次:固定b 值和扩散敏感梯度方向数(MPGs),分别层厚3 mm、4 mm、5 mm扫描;第2次:固定b值和层厚,分别MPGs=6、15、25扫描;第3次:固定MPGs、层厚,分别b值800 s/mm^2、1 000 s/mm^2、1 200 s/mm^2扫描。由2名医师行可视化评价,采用Kruskal-Wallis H检验、SNK q检验行统计学分析。结果 第1次层厚3 mm、4 mm、5 mm对应成像质量评分平均值为:0.7±0.470、1.45±0.510、1.35±0.489;层厚4 mm、5 mm成像质量无明显统计学差异(P>0.05),与层厚3 mm成像质量有统计学差异(P<0.05)。第2次MPGs=6、15、25对应成像质量评分平均值为:0.5±0.513、0.7±0.571、1.35±0.489;前两者成像质量无明显统计学差异(P>0.05),与MPGs=25成像质量有统计学差异(P<0.05)。第3次b值800 s/mm^2、1 000 s/mm^2、1 200 s/mm^2相应图像质量评分平均值为:0.85±0.366、1.45±0.510、0.95±0.510;b值800 s/mm^2、1 200 s/mm^2成像质量无明显统计学差异(P>0.05),与b值1 000 s/mm^2成像质量有统计学差异(P<0.05)。结论3.0T MR正常膝部周围神经DTI序列合适的层厚、MPGs及b值分别为:4 mm/5 mm、25、1 000 s/mm^2。Objective To investigate the three proper key parameters of the normal knees peripheral nerves in the DTI of 3.0T MR.Methods DTI scans were performed experimentally three times for the knees of 32 healthy volunteers using 3.0T MR(interlayer space 0 mm).The b value and MPGs were fixed during the first scan using thickness of 3,4,5 mm,respectively.Then unique b value and layer thickness were used to scan with the number of MPGs equal to 6,15 and 25.In the third rime,the b value was 800,1 000, 1 200 s/mm^2 when another two were fixed.These images were evaluated visually by two radiologists.The Kruskal-Wallis H test and SNK q test were used to conduct statistical analysis.Results At the first time,the average values of the correspond ing imaging quality score were 0.7 ±0.470,1.45 ±0.510 and 1.35 ±0.489 using layer thickness of 3,4,5 m m,respeetively.There was no significant statistical difference (P>0.05)between layer thickness of 4 mm and 5 mm.However,statistical differences were significant(P<0.05 )when compared 4 mm,5 mm with 3 mm,respectively.The value changed to 0.5±0.513,0.7±0.571,1.35±0.489 in the second time when the number of MPGs=6,15,25.Statistical differences were not significant (P ,0.05)when the first two number of MPGs compared with the last one,while statisitical difference (P<0.05)were shown between 25 and the others.At the last time,the average value was 0.85±0.366,1.45±0.510,0.954-0.510 while the b value became 800,1 000,1 200 s/mm^2 .The difference of statistic was not shown when compared the variable value of 800 s/mm2 and 1 200 s/mm^2.But,when the b value was 1 000 s/mm^2 ,the result was opposite(P<0.05)by comparing it with the other two.Conclusion The suitable layer thickness,the number of MPGs,and the b value of DTI in the 3.0T MR scan for the knees peripheral nerves were:4 mm/5 mm,25 and 1 000 s/mm^2 ,respectively.

关 键 词：扩散张量成像 层厚 扩散敏感梯度数 B值 

分 类 号：R445.2[医药卫生—影像医学与核医学] R323.72[医药卫生—诊断学]