肺部孤立性实性病变的磁共振DWI技术优选

The optimization of magnetic resonance diffusion weighted imaging technique for solitary solid lung lesions

目的:比较快速自旋回波扩散加权成像(TSE-DWI)与平面回波(EPI)DWI对肺部孤立性实性病灶的成像质量,探讨TSE-DWI在肺部孤立性病灶中的临床应用价值。方法:对40例肺孤立性实性病变患者分别行TSE-DWI及EPI-DWI扫描(b=600s/mm^2),测量并比较两个序列图像上病灶的信噪比、病灶及脊髓的ADC值、变形率、成像效率及图像质量的主观评分。结果:TSE-DWI序列的病灶成像效率为100%(40/40);EPI-DWI的成像效率为90%(36/40),4例病灶的图像变形严重,无法测量其ADC值。TSE-DWI序列上脊髓的ADC值高于EPI-DWI序列(P<0.01)。病灶在TSE-DWI上的ADC值高于EPI-DWI序列(P=0.007)。病灶在TSE-DWI上的变形率明显低于EPI-DWI序列(P<0.01)。图像质量的主观评分,TSE-DWI序列中39例为3分、1例为2分,EPI序列中主观评分19例为3分、17例为2分、4例为1分(图像变形无法测量),两组间图像质量主观评分的差异具有统计学意义(P<0.001)。结论:TSE-DWI的病灶变形率、成像效率及主观评分均较EPI-DWI序列高,可作为胸部孤立性病变的常规扫描序列。

Objective:The aim of this study was to compare turbo spin echo diffusion weighted imaging(TSE-DWI)and echo planar diffusion weighted imaging(EPI-DWI)on image quality,deformation rate,imaging efficiency and subjective score of image quality of solitary solid lung lesions.Methods:40 cases with solitary solid lung lesions were scanned with TSE-DWI and EPI-DWI sequences(b=600s/mm^2).Parameters including signal-to-noise ratio(SNR),apparent diffusion coefficient(ADC),deformation rate,imaging efficiency,and subjective score of the image quality of the two sequences were measured and compared.Results:The imaging efficiency of TSE-DWI sequence was 100%(40/40),while 4 cases of EPI-DWI were severely deformed and ADC value could not be mea-sured with 90%(36/40)imaging efficiency.The ADC value of the spinal cord of TSE-DWI sequence was higher than that of EPI-DWI sequence(P<0.01).The ADC value of 40 lesions of TSE-DWI was higher than that of EPI-DWI of 36 lesions(P=0.007).The subjective score of TSE-DWI sequence was 3 points in 39 cases and 2 points in one case;while the EPI sequence was 3 points in 19 cases and 2 points in 17 cases and 1 point in 4 cases(measurement was impossible due to severe distortion);there was significant difference between the two sequences(P<0.001).Conclusion:The deformation rate,imaging efficiency and subjective score of the TSE-DWI sequence are higher than those of the EPI-DWI sequence,TSE-DWI can be used as a routine sequence in the examination of solitary lung lesions.