3.0T MR腹部成像带宽对图像质量的影响

目的探讨带宽的调整对于3.0T MR腹部成像质量的影响。方法选取行3.0T上腹部MRI检查患者38例,同时进行常规带宽和高带宽快速自旋回波序列轴位脂肪抑制T2WI成像,由2名高年资放射科医师对两组图像整体成像质量进行评分,采用wilconxon配对符号秩和检验分析两组图像的信号噪声比(SNR)和图像整体质量评分差异。结果高带宽组图像的SNR较之常规带宽组有所下降,但图像总体质量评分显著提高(P值均<0.001);同时,高带宽组SNR和图像总体质量评分较之常规带宽组的比率中位数、平均绝对值离差、离散系数、变异系数分别为87.40%和115.50%、0.12和0.16、0.13和0.14、19.50%和17.80%,数据离散程度较小,比率变异较小,整体比率趋于集中。结论使用高带宽在有限牺牲部分SNR情况下可有效减弱快速自旋回波序列T2WI轴位图像的呼吸运动伪影干扰、改善成像质量。

Effect of bandwidth on abdominal imaging quality in 3.0 T MR

Objective To study the effect of imaging quality in abdomenbybandwidthadjustmentin 3.0 T.Methods A total of 38 patients wer eenrolled from December 2018 to March 2019in this study.For each subject,the protocol of T2 fast spin echo sequence with fat suppression in axial scan was repeated,acquiring two groups of images with conventional bandwidthandhigh-bandwidth.Two experienced doctors blinded to the parameter of bandwidth assigned a respiratory motion-related artifactscore 1(nondiagnostic images)to 5(no motion)for two groups of images.Signal intensity-to-noise ratio(SNR)was evaluated inliver.Results The SNR of the conventional bandwidth group was higher than that of high-bandwidth group(P<0.001)whereas doctors scored overall image quality the former was inferior to the latter(P<0.001).The Median,Mean Absolute Deviation,Coefficient of Dispersion,Coefficient of Variation of the SNR and the image overall quality score of twogroups were 87.40%and 115.50%,0.12 and 0.16,0.13 and 0.14,19.50%and 17.80%,respectively.Conclusion The imaging quality of T2 fast spin echo sequence imaging of abdomen in 3.0 T could be improved by increased the bandwidth of acquisition although this method can reduction of SNR of images.