3.0T MR快速电影相位对比序列测量液体流速影响因素分析  

Influencing factors of measurement of fluid velocity by using MR Fast CINE PC sequence at 3.0 T

作　　者：李晖[1] 王志强[1] 宋利宏[2] 尚华[3] 闫乐卡[3] 刘怀军[3] 

机构地区：[1]河北联合大学附属医院MR室,河北唐山063000 [2]邯郸市中心医院影像科 [3]河北医科大学第二医院医学影像科

出　　处：《实用放射学杂志》2013年第9期1493-1495,1541,共4页Journal of Practical Radiology

摘　　要：目的 通过建立稳态流体模型,对3.0T MR快速电影相位对比（Fast CINE phase contrast,Fast CINE PC）序列测量液体流速的各种外在影响因素进行分析,从而提高测量结果的准确性.方法将直径为3.0 mm的医用塑料管固定在水模中,塑料管的一端连接高压注射器,高压注射器以不同流速向管腔内注射生理盐水,管的另一端连入量筒.将流体模型置于头部8通道线圈中心.应用3.0T MR Fast CINE PC序列扫描,扫描层面垂直于管腔长轴.在不同流速、不同倾斜角度、不同感兴趣区大小、不同层面及管腔内不同点对流速进行测量.对结果进行统计学分析.结果测量流速与真实流速之间差异无统计学意义（P＆gt;0.05）.不管管腔在各个方向有无角度,测量流速与实际流速间差异均无统计学意义（P＆gt;0.05）.不同大小感兴趣区测量流速与感兴趣区大小呈负相关,相关系数=-0.99（P＆lt;0.000 1）.不同大小感兴趣区测量流量与感兴趣区大小呈正相关,相关系数=0.98（P＆lt;0.000 1）.不同层面流速与实际流速间差异无统计学意义（P＆gt;0.05）.管腔内不同点流速与实际流速间差异有统计学意义（P＆lt;0.05）.结论 准确进行层面定位、准确选择感兴趣区及窗宽窗位是保证测量结果准确性的重要前提.Objective To analyze various externally influencing factors of hydrodynamic measurement with 3.0 T MR Fast CINE PC sequence using a steady fluid flow phantom in order to improve measured accuracy. Methods A plastic tube with diameter 3.0 mm filled with liquid was fixed in a water phantom. One terminal of the tube was connected to the high pressure injector for injecting saline with different velocity,and another terminal was inserted into a cylinder for recovering the saline. The phantom was placed in the center of a 8-channel array head coil. Fast CINE PC sequence was used for scanning with the scanning plane perpendicular to the major axis of tube. The velocities at different flow rates,angles,regions of interest （ROI） ,slices,and points in the lumen were measured. Statistical analyse was performed. Results There was no statistical difference between the measured velocity and actual velocity （t= ].49,P=0.18）,so was the same difference whatever any angles of the tube （t=2.01,P=0.09）. The measured velocity at differ ent R（）I was negative correlated with the area of ROI （r=0.99,P〈0. 0001） ,however,the measured flow volume was opposite （r =0.98,P〈C0. 0001）. There was no difference between the measured velocity at different slices and actual velocity （t=0.97, P= 0.36}. There was difference between the measured velocity at different points in the lumen and actual velocity （t=2.57, P=0.03）. Conclusion Precise position of the section, and selection of the ROI, window width and level are the important prerequisite to accurate measurement of fluid velocity with MR Fast CINE PC sequence.

关 键 词：相位对比 电影 模型 影响因素 磁共振成像 

分 类 号：R-331[医药卫生] R445.2