目的探讨MR 3D CUBE技术对膝关节前交叉韧带损伤的诊断价值。材料与方法对膝关节损伤拟行手术病人术前行MR扫描,以关节镜所见为参考依据,对80例患者86个膝关节行常规MRI序列扫描后加扫3D CUBE T2WI序列,运用AW4.4工作站对3D图像进行后...目的探讨MR 3D CUBE技术对膝关节前交叉韧带损伤的诊断价值。材料与方法对膝关节损伤拟行手术病人术前行MR扫描,以关节镜所见为参考依据,对80例患者86个膝关节行常规MRI序列扫描后加扫3D CUBE T2WI序列,运用AW4.4工作站对3D图像进行后处理重建。分别与关节镜术后结果进行对比分析,计算常规MRI序列及3D CUBE技术在诊断前交叉韧带损伤中的特异度、灵敏度及准确度。结果 3D CUBE T2WI序列在诊断前交叉韧带损伤特异度89%、灵敏度95%、准确度84%;常规MRI序列在诊断前交叉韧带损伤的特异度68%、灵敏度83%、准确度51%。结论 3DCUBE序列扫描时间短,图像可多角度任意旋转,可显示完整前交叉韧带,对前交叉韧带损伤的特异度、灵敏度及准确度较常规MRI序列高。展开更多
目的 采用功能性磁共振技术研究微重力环境对工作记忆的影响. 方法 9名健康男性青年头低位卧床4周.卧床前、卧床1周时和卧床4周后各对其进行1次倒数2项工作记忆任务的功能磁共振成像扫描. 结果 模拟失重前,工作记忆任务激活的脑区有双...目的 采用功能性磁共振技术研究微重力环境对工作记忆的影响. 方法 9名健康男性青年头低位卧床4周.卧床前、卧床1周时和卧床4周后各对其进行1次倒数2项工作记忆任务的功能磁共振成像扫描. 结果 模拟失重前,工作记忆任务激活的脑区有双侧额叶(ba46/9、47、6)、前扣带回(ba32)、双侧顶叶(ba7)、双侧枕叶(19/18)和左侧丘脑.模拟失重1周时,激活脑区的范围和信号强度变化显著.模拟失重4周后,激活脑区与卧床前趋于相似. 结论 ①模拟失重状态时,人脑工作记忆功能状态有明显的变化,主要表现为功能脑区激活范围和部位的变化;②模拟失重环境对工作记忆信息的被动贮存影响不大,但对信息的主动复述维持及中央执行系统的信息操作功能有明显、可逆的影响;③失重1周时,人脑激活区变化显著.失重4周时,人脑已经开始逐步适应,但未正常化.
abstract：
objective to investigate the effect of simulated weightlessness on human working memory by using functional magnetic resonance imaging (fmri). methods nine young male volunteers underwent - 6° head-down bed rest (hdbr) for four weeks. series fmri scans were performed on them one day before experiment, one week and four weeks after hdbr with block designed 2-back working memory task. results the engagement of working memory before hdbr produced significant activation in the prefrontal cortex (bi-lateralized ba46/9, left> right; bi- lateralized ba47; right ba6), anterior cingulated gyrus(ba32), bi-lateralized posterior parietal lobe (bat,left>right), bi-lateralized occipital lobe (ba19/18) and left thalamus. compared with those before hdbr, the engagement of working memory one week after hdbr brain activation size and signal magnitude changed significantly. however, compared with those before hdbr, there was unsignificant change four weeks after hdbr. conclusions ①the brain activation size and location of working memory would change after hdbr. ②hdb展开更多
目的应用MR 3D CUBE T2WI序列重建图像显示前交叉韧带的形态及信号强度。方法采用GE Signa HDxt 1.5T超导型磁共振机器和膝关节表面线圈,应用MR 3D CUBE T2WI序列扫描,运用再将3D图像传至AW.4.4工作站,进行图像后处理,显示膝关节的前交...目的应用MR 3D CUBE T2WI序列重建图像显示前交叉韧带的形态及信号强度。方法采用GE Signa HDxt 1.5T超导型磁共振机器和膝关节表面线圈,应用MR 3D CUBE T2WI序列扫描,运用再将3D图像传至AW.4.4工作站,进行图像后处理,显示膝关节的前交叉韧带。结果 MR 3D CUBE T2WI序列可以完整的显示膝关节前交叉韧带的形态及信号强度。结论 MR 3D CUBE T2WI序列扫描时间短,图像可多角度任意旋转,可以清晰的显示前交叉韧带,弥补了普通MR扫描序列的对前交叉韧带显示的缺憾,对临床诊疗提供重要依据。展开更多
文摘目的探讨MR 3D CUBE技术对膝关节前交叉韧带损伤的诊断价值。材料与方法对膝关节损伤拟行手术病人术前行MR扫描,以关节镜所见为参考依据,对80例患者86个膝关节行常规MRI序列扫描后加扫3D CUBE T2WI序列,运用AW4.4工作站对3D图像进行后处理重建。分别与关节镜术后结果进行对比分析,计算常规MRI序列及3D CUBE技术在诊断前交叉韧带损伤中的特异度、灵敏度及准确度。结果 3D CUBE T2WI序列在诊断前交叉韧带损伤特异度89%、灵敏度95%、准确度84%;常规MRI序列在诊断前交叉韧带损伤的特异度68%、灵敏度83%、准确度51%。结论 3DCUBE序列扫描时间短,图像可多角度任意旋转,可显示完整前交叉韧带,对前交叉韧带损伤的特异度、灵敏度及准确度较常规MRI序列高。
文摘目的 采用功能性磁共振技术研究微重力环境对工作记忆的影响. 方法 9名健康男性青年头低位卧床4周.卧床前、卧床1周时和卧床4周后各对其进行1次倒数2项工作记忆任务的功能磁共振成像扫描. 结果 模拟失重前,工作记忆任务激活的脑区有双侧额叶(ba46/9、47、6)、前扣带回(ba32)、双侧顶叶(ba7)、双侧枕叶(19/18)和左侧丘脑.模拟失重1周时,激活脑区的范围和信号强度变化显著.模拟失重4周后,激活脑区与卧床前趋于相似. 结论 ①模拟失重状态时,人脑工作记忆功能状态有明显的变化,主要表现为功能脑区激活范围和部位的变化;②模拟失重环境对工作记忆信息的被动贮存影响不大,但对信息的主动复述维持及中央执行系统的信息操作功能有明显、可逆的影响;③失重1周时,人脑激活区变化显著.失重4周时,人脑已经开始逐步适应,但未正常化.
abstract：
objective to investigate the effect of simulated weightlessness on human working memory by using functional magnetic resonance imaging (fmri). methods nine young male volunteers underwent - 6° head-down bed rest (hdbr) for four weeks. series fmri scans were performed on them one day before experiment, one week and four weeks after hdbr with block designed 2-back working memory task. results the engagement of working memory before hdbr produced significant activation in the prefrontal cortex (bi-lateralized ba46/9, left> right; bi- lateralized ba47; right ba6), anterior cingulated gyrus(ba32), bi-lateralized posterior parietal lobe (bat,left>right), bi-lateralized occipital lobe (ba19/18) and left thalamus. compared with those before hdbr, the engagement of working memory one week after hdbr brain activation size and signal magnitude changed significantly. however, compared with those before hdbr, there was unsignificant change four weeks after hdbr. conclusions ①the brain activation size and location of working memory would change after hdbr. ②hdb
文摘目的应用MR 3D CUBE T2WI序列重建图像显示前交叉韧带的形态及信号强度。方法采用GE Signa HDxt 1.5T超导型磁共振机器和膝关节表面线圈,应用MR 3D CUBE T2WI序列扫描,运用再将3D图像传至AW.4.4工作站,进行图像后处理,显示膝关节的前交叉韧带。结果 MR 3D CUBE T2WI序列可以完整的显示膝关节前交叉韧带的形态及信号强度。结论 MR 3D CUBE T2WI序列扫描时间短,图像可多角度任意旋转,可以清晰的显示前交叉韧带,弥补了普通MR扫描序列的对前交叉韧带显示的缺憾,对临床诊疗提供重要依据。
