多激励次数自由呼吸T1 VIBE序列在肝脏MR中的应用

目的探讨多激励次数自由呼吸VIBE序列在肝脏MR中的应用价值。方法选取40例屏气效果不佳肝脏MR检查患者(无法配合屏气15s)分别行多激励次数自由呼吸T1 VIBE扫描和常规屏气T1 VIBE扫描,扫描结果按自由呼吸组及常规屏气组分组;采用"5分法"对每组图像总体质量进行主观评分,并分别测量肝右叶、肝左叶及脾脏的SNR,比较两组图像差异。结果多激励次数自由呼吸T1 VIBE序列图像主观评分明显高于常规屏气T1 VIBE序列,差异有统计学意义(P<0.01)。多激励次数自由呼吸T1 VIBE序列的平均SNR为:肝右叶71.6,肝左叶64.11,脾脏59.53,常规屏气T1 VIBE序列的平均SNR为:肝右叶23.18,肝左叶18.58,脾脏18;多激励次数自由呼吸T1 VIBE序列的SNR均高于常规屏气T1 VIBE序列(P<0.01)。结论多激励次数自由呼吸T1 VIBE序列可明显减少腹部呼吸运动伪影,提高图像整体质量增加SNR;在肝脏MR检查中具有重要的应用价值。

The Application of Multiple Number of Excitation(NEX) Free Breathing T1 VIBE Sequence in Liver MR

Objective To investigate the application value of multiple NEX free breathing VIBE sequence in liver MR. Methods Forty cases of patients with poor breathholding effect(unable to cooperate with breath-holding for 15 s)and undergone liver MR examination were performed multiple NEX free breathing T1 VIBE scanning and conventional breath-holding T1 VIBE scanning. The results were divided into free breathing group and conventional breath-holding group. The overall image quality of each group was subjectively scored by using the "5-point method". The SNR of the left and right lobes of the liver and the spleen were measured, and the image difference between the two groups was compared. Results The image subjective score of multiple NEX free breathing T1 VIBE sequence was significantly higher than that of the conventional breath-holding T1 VIBE sequence(P<0.01). The average SNR of multiple NEX free breathing T1 VIBE sequence was 71.6 for the right lobe of the liver, 64.11 for the left lobe of the liver and 59.53 for the spleen. The average SNR of conventional breath-holding T1 VIBE sequence was 23.18 for the right lobe of the liver, 18.58 for the left lobe of the liver and 18 for the spleen. The SNR of multiple NEX free breathing T1 VIBE sequence was higher than that of conventional breath-holding T1 VIBE sequence(P<0.01). Conclusion Multiple NEX free breathing T1 VIBE sequence can significantly reduce the artifacts of abdominal respiratory movement, enhance overall image quality and increase SNR, so it has important application value in liver MR examination.