目的:探究高分辨率血管壁成像时利用可变翻转角实现最优化采集的3D快速自旋回波序列(3D-SPACE)T1压脂与非压脂序列对大脑中动脉(middle cerebral artery,MCA)狭窄病人图像信号、血管壁及斑块情况的影响。方法:选取2021年1月—2022年12...目的:探究高分辨率血管壁成像时利用可变翻转角实现最优化采集的3D快速自旋回波序列(3D-SPACE)T1压脂与非压脂序列对大脑中动脉(middle cerebral artery,MCA)狭窄病人图像信号、血管壁及斑块情况的影响。方法:选取2021年1月—2022年12月于滨州市中心医院接受颅内磁共振血管成像(MR angiography,MRA)检查并确诊的MCA狭窄患者72例为研究对象,患者均接受MCA MRI检查,然后再分别用3D SPACE T1压脂与非压脂序列测量,分析图像信号差异情况,对比不同序列测量的血管断面、管腔及斑块面积情况及图像质量主观评价;分析不同医师图像质量评分的一致性情况。结果:72例患者中,不同序列测量均可以清晰地将MCA斑块显示出来,但测量出的信号存在明显的差异。不同序列测量血管断面、管腔面积对比差异不显著(P>0.05);3D SPACE T1非压脂序列测量斑块面积大于压脂序列测量面积(P<0.05);2种序列管腔显示情况对比差异无统计学意义(P>0.05),其他图像质量对比差异有统计学意义(P<0.05)。2名医生图像质量评分具有良好的一致性。结论:高分辨率血管壁成像时3D SPACE T1非压脂序更有助于对MCA狭窄病人图像信号、血管壁及斑块的测量,可为临床提供治疗依据。展开更多
Objective Io evaluate changes in morphology of the cesarean scar and uterus between one and two years after cesarean section using high-resolution,three dimensional T2-weighted sampling perfection with application opt...Objective Io evaluate changes in morphology of the cesarean scar and uterus between one and two years after cesarean section using high-resolution,three dimensional T2-weighted sampling perfection with application optimized contrast using diflerent flip angle evolutions Magnetic Resonance Imaging(3DT2w SPACE MRI).Methods This prospective study was performed to investigate morphological changes in the cesarean scars and uterus from one to two years after cesarean section using high-resolution,3D T2w SPACE MRI.The healthy volunteers having no childbearing history were recruited as the controls.All data were measured by two experienced radiologists.All data with normal distribution between the one-year and two-year groups were compared using a paired-sample t test or independent t test.Results Finally,46 women took a pelvic MR examination one year after cesarean section,and a subset of 15 completed the same examination again after two years of cesarean section.Both the uterine length and the anterior wall thickness after two years of cesarean section(5.75±0.46 and 1.45±0.35 cm)were significantly greater than those measured at one year(5.33±0.59 and 1.25±0.27 cm)(t=-2.363 and-2.175,P=0.033 and 0.048).No significant difference was shown in myometrial thickness two years after cesarean section(1.45±0.35 cm)with respect to the control group(1.58±0.21 cm,P=0.170).Nine women who underwent MRI twice were considered to have scar diverticula one year after cesarean section,and still had diverticula two years after cesarean section.The thickness,height,and width of the uterine scar showed no significant change from one to two years(all P>0.05).Conclusions 3D T2w SPACE MRI provides overall morphologic details and shows dynamic changes in the scar and the uterus between one and two years after cesarean section.Scar morphology after cesarean section reached relatively stable one year after cesarean section,and uterine morphology was closer to normal two years after cesarean section.展开更多
In Newton’s classical physics, space and time are treated as absolute, independent quantities and can be discussed separately. In Special Relativity, Einstein proved that space and time are relative and dependent and...In Newton’s classical physics, space and time are treated as absolute, independent quantities and can be discussed separately. In Special Relativity, Einstein proved that space and time are relative and dependent and therefore must not be treated separately. Minkowski adopted four-dimensional space-time frames (4-d s-t frames), which indirectly revealed the dependency of space and time with the addition of a constraint for an event interval. We are not able to visualize 4-d s-t frames. Since space and time are inseparable, three-dimensional space-time frames (3-d s-t frames) can be constructed by embedding time into space to directly show the interdependency of space and time. Time contraction and length contraction can also be depicted graphically using 3-d s-t frames. We have much better understanding reality of space and time in 3-d s-t frames. This will lead to Contextual Reality for better understanding the universe.展开更多
文摘目的:探究高分辨率血管壁成像时利用可变翻转角实现最优化采集的3D快速自旋回波序列(3D-SPACE)T1压脂与非压脂序列对大脑中动脉(middle cerebral artery,MCA)狭窄病人图像信号、血管壁及斑块情况的影响。方法:选取2021年1月—2022年12月于滨州市中心医院接受颅内磁共振血管成像(MR angiography,MRA)检查并确诊的MCA狭窄患者72例为研究对象,患者均接受MCA MRI检查,然后再分别用3D SPACE T1压脂与非压脂序列测量,分析图像信号差异情况,对比不同序列测量的血管断面、管腔及斑块面积情况及图像质量主观评价;分析不同医师图像质量评分的一致性情况。结果:72例患者中,不同序列测量均可以清晰地将MCA斑块显示出来,但测量出的信号存在明显的差异。不同序列测量血管断面、管腔面积对比差异不显著(P>0.05);3D SPACE T1非压脂序列测量斑块面积大于压脂序列测量面积(P<0.05);2种序列管腔显示情况对比差异无统计学意义(P>0.05),其他图像质量对比差异有统计学意义(P<0.05)。2名医生图像质量评分具有良好的一致性。结论:高分辨率血管壁成像时3D SPACE T1非压脂序更有助于对MCA狭窄病人图像信号、血管壁及斑块的测量,可为临床提供治疗依据。
文摘Objective Io evaluate changes in morphology of the cesarean scar and uterus between one and two years after cesarean section using high-resolution,three dimensional T2-weighted sampling perfection with application optimized contrast using diflerent flip angle evolutions Magnetic Resonance Imaging(3DT2w SPACE MRI).Methods This prospective study was performed to investigate morphological changes in the cesarean scars and uterus from one to two years after cesarean section using high-resolution,3D T2w SPACE MRI.The healthy volunteers having no childbearing history were recruited as the controls.All data were measured by two experienced radiologists.All data with normal distribution between the one-year and two-year groups were compared using a paired-sample t test or independent t test.Results Finally,46 women took a pelvic MR examination one year after cesarean section,and a subset of 15 completed the same examination again after two years of cesarean section.Both the uterine length and the anterior wall thickness after two years of cesarean section(5.75±0.46 and 1.45±0.35 cm)were significantly greater than those measured at one year(5.33±0.59 and 1.25±0.27 cm)(t=-2.363 and-2.175,P=0.033 and 0.048).No significant difference was shown in myometrial thickness two years after cesarean section(1.45±0.35 cm)with respect to the control group(1.58±0.21 cm,P=0.170).Nine women who underwent MRI twice were considered to have scar diverticula one year after cesarean section,and still had diverticula two years after cesarean section.The thickness,height,and width of the uterine scar showed no significant change from one to two years(all P>0.05).Conclusions 3D T2w SPACE MRI provides overall morphologic details and shows dynamic changes in the scar and the uterus between one and two years after cesarean section.Scar morphology after cesarean section reached relatively stable one year after cesarean section,and uterine morphology was closer to normal two years after cesarean section.
文摘In Newton’s classical physics, space and time are treated as absolute, independent quantities and can be discussed separately. In Special Relativity, Einstein proved that space and time are relative and dependent and therefore must not be treated separately. Minkowski adopted four-dimensional space-time frames (4-d s-t frames), which indirectly revealed the dependency of space and time with the addition of a constraint for an event interval. We are not able to visualize 4-d s-t frames. Since space and time are inseparable, three-dimensional space-time frames (3-d s-t frames) can be constructed by embedding time into space to directly show the interdependency of space and time. Time contraction and length contraction can also be depicted graphically using 3-d s-t frames. We have much better understanding reality of space and time in 3-d s-t frames. This will lead to Contextual Reality for better understanding the universe.
