An ever-increasing number of 3.0 Tesla(T) magnets are installed worldwide. Moving from the standard of 1.5 T to higher field strength implies a number of potential advantage and drawbacks, requiring careful optimizati...An ever-increasing number of 3.0 Tesla(T) magnets are installed worldwide. Moving from the standard of 1.5 T to higher field strength implies a number of potential advantage and drawbacks, requiring careful optimization of imaging protocols or implementation of novel hardware components. Clinical practice and literature review suggest that state-of-the-art 3.0 T is equivalent to 1.5 T in the assessment of focal liver lesions and diffuse liver disease. Therefore, further technical improvements are needed in order to fully exploit the potential of higher field strength.展开更多
AIM:To determine the optimal b value of diffusionweighted imaging for detecting active inflammation in Crohn's disease.METHODS:Thirty-one patients clinically diagnosed with active Crohn’s disease were referred fo...AIM:To determine the optimal b value of diffusionweighted imaging for detecting active inflammation in Crohn's disease.METHODS:Thirty-one patients clinically diagnosed with active Crohn’s disease were referred for magnetic resonance examination.All patients were scanned on a3.0T magnetic resonance scanner using the same protocol involving four different b values(800,1500,2000and 2500 s/mm2).The diagnostic effect of diffusionweighted imaging was evaluated and compared with endoscopic findings.The diffusion-weighted image quality of four b value groups was evaluated and apparent diffusion coefficient was measured for both nor-mal and inflammatory intestinal segments.RESULTS:The contrast-to-noise ratio and signal-tonoise ratio were not satisfied when b value 2000 or2500 s/mm2 was adopted(36.52±14.95 vs 34.78±24.83,P>0.05;53.58±23.45 vs 47.58±29.67,P>0.05).The qualitative image quality was not enough to meet diagnostic requirement.No matter which b value was chosen,the apparent diffusion coefficient of inflammatory intestinal segments was significantly lower than that of normal intestinal segments(1.38±0.28 vs 2.00±0.38,P<0.01;1.09±0.20 vs 1.50±0.28,P<0.01;0.95±0.19 vs 1.34±0.28,P<0.01;0.88±0.14 vs 1.20±0.21,P<0.01).The lesion detection rate(90.32%),diagnostic sensitivity(81.18%)and specificity(95.10%)would be appropriate when b value 1500 s/mm2 was adopted.CONCLUSION:High b value is suitable for intestinal DW examination on a high field MR scanner.展开更多
目的探讨磁共振谷氨酸化学交换饱和转移成像技术诊断脑肿瘤的价值及其可行性。方法对2014年4月~2015年4月于汕头大学医学院附属第二医院经手术或临床确诊的28例脑肿瘤患者进行MRI检查,年龄23~80岁。患者于静息状态下应用GE 3.0 T Signa...目的探讨磁共振谷氨酸化学交换饱和转移成像技术诊断脑肿瘤的价值及其可行性。方法对2014年4月~2015年4月于汕头大学医学院附属第二医院经手术或临床确诊的28例脑肿瘤患者进行MRI检查,年龄23~80岁。患者于静息状态下应用GE 3.0 T Signa磁共振扫描仪进行常规的T1WI、T2WI扫描,以及应用自行设计的化学交换饱和转移序列,在偏离水质子峰3.0 ppm处激发特定的脉冲进行扫描,并经计算机处理后与常规序列进行对比分析。同时患者也在该机器上进行氢质子磁共振波谱成像用于数据融合对比。结果对得到的谷氨酸化学交换饱和转移(Glu CEST)成像进行对比分析,胶质瘤瘤体及瘤体周边组织呈明显高信号改变;转移瘤瘤体呈低信号改变,瘤体周边组织呈明显高信号改变;而脑膜瘤瘤体呈低信号改变;以上Glu CEST成像中区域信号改变大致符合氢质子磁共振波谱中谷氨酸浓度定量改变。结论谷氨酸化学交换饱和转移成像作为一种新起的磁共振成像技术,能为脑肿瘤及瘤周情况提供更丰富的代谢物信息,对脑肿瘤的诊断、治疗及预后提供更好的帮助。展开更多
[目的]探讨3.0 T MRI对腕关节不稳患者近排腕骨间韧带损伤早期诊断及腕关节角测量的价值。[方法] 2015年1月~2017年1月于本院就诊并被临床医师初诊为腕关节不稳患者120例为试验组,招募志愿者30例健康成年人为对照组。对两组进行MRI诊...[目的]探讨3.0 T MRI对腕关节不稳患者近排腕骨间韧带损伤早期诊断及腕关节角测量的价值。[方法] 2015年1月~2017年1月于本院就诊并被临床医师初诊为腕关节不稳患者120例为试验组,招募志愿者30例健康成年人为对照组。对两组进行MRI诊断检查,分析比较两组舟月韧带(SLIL)、月三角韧带(LTIL)的MRI信号强度,SLIL和LTIL的直径及舟月骨角、腕骨角、桡月骨角。[结果]试验组腕关节SLIL和LTIL的MRI信号强度高于对照组,差异具有统计学意义(P<0.05)。试验组的SLIL近侧部分直径[(7.40±1.31) mm vs (5.73±0.78) mm,P<0.05],LTIL近侧直径[(5.66±0.77) mm vs (4.93±1.09) mm,P<0.05]均大于对照组,差异有统计学意义。此外,试验组舟月角[(88.75±11.50)°vs (57.65±8.42)°,P<0.05]、腕骨角[(143.12±6.74)°vs (137.59±7.31)°,P<0.05]和桡月角[(11.79±4.69)°vs (6.18±1.75)°,P<0.05]为均大于对照组,差异具有统计学意义。[结论] 3.0 T MRI对腕关节不稳患者近侧列腕骨间韧带损伤的患者可进行早期诊断,本研究的测量结果可为临床医生提供参考价值。展开更多
文摘An ever-increasing number of 3.0 Tesla(T) magnets are installed worldwide. Moving from the standard of 1.5 T to higher field strength implies a number of potential advantage and drawbacks, requiring careful optimization of imaging protocols or implementation of novel hardware components. Clinical practice and literature review suggest that state-of-the-art 3.0 T is equivalent to 1.5 T in the assessment of focal liver lesions and diffuse liver disease. Therefore, further technical improvements are needed in order to fully exploit the potential of higher field strength.
基金Supported by National Basic Research Program of China,No.2012CB932600Shanghai Leading Academic Discipline Project,No.S30203
文摘AIM:To determine the optimal b value of diffusionweighted imaging for detecting active inflammation in Crohn's disease.METHODS:Thirty-one patients clinically diagnosed with active Crohn’s disease were referred for magnetic resonance examination.All patients were scanned on a3.0T magnetic resonance scanner using the same protocol involving four different b values(800,1500,2000and 2500 s/mm2).The diagnostic effect of diffusionweighted imaging was evaluated and compared with endoscopic findings.The diffusion-weighted image quality of four b value groups was evaluated and apparent diffusion coefficient was measured for both nor-mal and inflammatory intestinal segments.RESULTS:The contrast-to-noise ratio and signal-tonoise ratio were not satisfied when b value 2000 or2500 s/mm2 was adopted(36.52±14.95 vs 34.78±24.83,P>0.05;53.58±23.45 vs 47.58±29.67,P>0.05).The qualitative image quality was not enough to meet diagnostic requirement.No matter which b value was chosen,the apparent diffusion coefficient of inflammatory intestinal segments was significantly lower than that of normal intestinal segments(1.38±0.28 vs 2.00±0.38,P<0.01;1.09±0.20 vs 1.50±0.28,P<0.01;0.95±0.19 vs 1.34±0.28,P<0.01;0.88±0.14 vs 1.20±0.21,P<0.01).The lesion detection rate(90.32%),diagnostic sensitivity(81.18%)and specificity(95.10%)would be appropriate when b value 1500 s/mm2 was adopted.CONCLUSION:High b value is suitable for intestinal DW examination on a high field MR scanner.
文摘[目的]探讨3.0 T MRI对腕关节不稳患者近排腕骨间韧带损伤早期诊断及腕关节角测量的价值。[方法] 2015年1月~2017年1月于本院就诊并被临床医师初诊为腕关节不稳患者120例为试验组,招募志愿者30例健康成年人为对照组。对两组进行MRI诊断检查,分析比较两组舟月韧带(SLIL)、月三角韧带(LTIL)的MRI信号强度,SLIL和LTIL的直径及舟月骨角、腕骨角、桡月骨角。[结果]试验组腕关节SLIL和LTIL的MRI信号强度高于对照组,差异具有统计学意义(P<0.05)。试验组的SLIL近侧部分直径[(7.40±1.31) mm vs (5.73±0.78) mm,P<0.05],LTIL近侧直径[(5.66±0.77) mm vs (4.93±1.09) mm,P<0.05]均大于对照组,差异有统计学意义。此外,试验组舟月角[(88.75±11.50)°vs (57.65±8.42)°,P<0.05]、腕骨角[(143.12±6.74)°vs (137.59±7.31)°,P<0.05]和桡月角[(11.79±4.69)°vs (6.18±1.75)°,P<0.05]为均大于对照组,差异具有统计学意义。[结论] 3.0 T MRI对腕关节不稳患者近侧列腕骨间韧带损伤的患者可进行早期诊断,本研究的测量结果可为临床医生提供参考价值。