不同弥散梯度方向在人脑磁共振弥散加权成像中的应用(英文)

Application of different diffuse gradient direction in human brain to diffusion-weighted image

背景:磁共振弥散加权成像中表观弥散系数对脑缺血性疾病的诊断,已被临床证实。不同弥散梯度方向在磁共振弥散加权成像对人脑不同部位的表观弥散系数的影响成为研究的重点之一。目的:探讨人脑不同弥散梯度方向弥散加权像上纹状体、顶叶皮层及放射冠的表观弥散系数值变化特征。设计:抽样调查。单位:暨南大学附属第一医院医学影像中心,暨南大学生命科学技术学院生物医学工程研究所。对象:选择2000-03/2001-03暨南大学附属华侨医院60名健康志愿者,男37名,女23名;年龄18～65岁。方法:对60名正常人脑分别进行不同弥散梯度方向(左-右;前-后;上-下)的弥散加权像检查,并测量其纹状体、顶叶皮层及放射冠的表观弥散系数值。主要观察指标:60名健康志愿者纹状体、顶叶皮层及放射冠表观弥散系数值。结果:60名健康志愿者均进入结果分析。纹状体、顶叶皮层的表观弥散系数值在不同弥散梯度方向上差异无显著性,而放射冠的表观弥散系数值在左-右、前-后、上-下轴向分别为(5.0±0.5),(4.2±0.6),(15.2±1.4)×104mm2/s,左-右、前-后方向与上-下方向比较,差异有显著性意义(P<0.01)。结论:纹状体、顶叶皮层表观弥散系数值不受弥散梯度方向影响;而放射冠的表观弥散系数值则受其影响,定量研究放射冠的弥散应该描述其弥散梯度方向。

BACKGROUND： The application of apparent diffusion coefficient （ADC） value to the diffusion-weighted image in the diagnosis of cerebral isebemic diseases is confirmed in clinic. The inffluence of different diffuse gradient direction in different lesions of human brain on diffusion-weighted image has become one of the focus researches of neuroradiology. OBJECTIVE： To explore the changing characters of the ADC value on diffusion weighted imaging with differer,t diffuse gradient directions of human corpora strintum, parietal cortex and corona radiata. DESIGN： A sample survey. SETTING： Medical Imaging Center, the First Affiliated Hospital of Jinan University; Institute of Biomedical Engineering, School of Life Science and Technology, Jinan Univeristy. PARTICIPANTS： Sixty healthy volunteers （37 males and 23 females） aged 18-65 years were selected from the Huaqian Hospital affiliated to Jinan University between March 2000 and March 2001. METHODS： The 60 volunteers received brain diffusion-weighted MR imaging in different directions （left-right, anterior-posterior, upper-down）, and the ADC values of corpus striatum, parietal cortex and corona radiata were measured, MAIN OUTCOME MEASURES： The ADC values of corpus striatum, parietal cortex and corona radiata were measured in the 60 healthy volunteers. RESULTS： All the 60 healthy volunteers entered the analysis of results. There were no significant differences between the ADC value of corpus striatum and that of parietal cortex in different directions; the mean ADC values of corona radiata in left-right, anterior-posterior, upper-down axial were （5.0±0.5）, （4.2±0.6）, （15.2±1.4）×10^4 mm^2/s, and there were significant differences between the fonner two and the latter （P 〈 0.01）. CONCLUSION： Diffuse gradient directions do not affect the ADC values of corpus striatum and parietal cortex, hut the ADC value of corona radiata is different. We should delineate the diffusion direction if we want to do quantitative studies on the diffusion of corona radiata.