同时多层采集技术在直肠分段读出平面回波成像中的可行性分析  

Feasibility analysis of simultaneous multi-slice acceleration technique in rectal readout-segmented echo-planar imaging

作　　者：周蜜 陈梅泞 黄红云 ZHOU Mi;CHEN Meining;HUANG Hongyun(Department of Radiology,Sichuan Provincial People's Hospital,Sichuan Academy of Medical Sciences,Chengdu 610000,China;Department of MR Scientific Marketing,Siemens Healthineers,Shanghai 200135,China)

机构地区：[1]四川省医学科学院·四川省人民医院放射科,四川成都610000 [2]西门子医疗系统有限公司磁共振科研部,上海200135

出　　处：《实用放射学杂志》2023年第7期1183-1187,共5页Journal of Practical Radiology

摘　　要：目的探讨同时多层采集(SMS)技术结合分段读出平面回波成像(rs-EPI)在直肠癌成像的可行性,比较SMS加速因子对成像质量、图像信噪比(SNR)及表观扩散系数(ADC)等方面的影响.方法对71例活检证实为直肠癌的患者进行3组rs-EPI扫描,其中包括常规rs-EPI,SMS加速因子分别为2和3的rs-EPI序列(2×SMS rs-EPI和3×SMS rs-EPI),b值取0 s/mm2和1000 s/mm2,根据5分法评分结果对上述EPI序列图像进行主观评分,比较扩散加权图像的SNR、对比噪声比(CNR)和ADC值.结果rs-EPI、2×SMS rs-EPI和3×SMS rs-EPI的扫描时间分别为137 s、60 s、51 s.在整体图像质量和SNR、CNR方面,rs-EPI和2XSMS rs-EPI的图像质量、SNR、CNR无统计学差异(P>0.05),但均优于3×SMS rs-EPI,差异有统计学意义(P<0.05).病灶ADC值和直肠正常组织的ADC值在3组序列中均存在统计学意义(P<0.05),且随着SMS加速因子的增加,ADC值呈下降趋势.结论SMS技术可显著缩短直肠癌的扫描时间,SMS加速因子最佳值为2时,获得的图像质量、ADC值等与rs-EPI接近.Objective To explore the feasibility of simultaneous multi-slice(SMS)combined with readout-segmented echo-planar imaging(rs-EPI)for rectal cancer imaging,and to compare the effects of SMS acceleration factors on imaging quality,image signalto-noise ratio(SNR)and apparent diffusion coefficient(ADC).Methods Three groups of rs-EPI scans were performed on 71 patients with biopsy-confirmed rectal cancer,including conventional rs-EPI and rs-EPI sequences with an SMS acceleration factor of 2 and 3(2XSMS rs-EPI and 3XSMS rs-EPI)with b-values of O and 1000 s/mm",respectively,and the above-mentioned EPI sequence images were subjectively scored according to the 5-point scale,the SNR,contrast-to-noise ratio(CNR),and ADC of the diffusion weighted images were compared.Results The scan times for rs-EPI,2XSMS rs-EPI,and 3XSMS rs-EPI were 137 s,60 s,and 51 s,respectively.rs-EPI and 2XSMS rs-EPI were not statistically different in terms of overall image quality,SNR and CNR(P>0.05)but were better than 3 XSMS rs-EPI with significant differences(P<0.05).There was a statistically significant difference between the ADC values of lesions and normal rectal tissues among the three groups of sequences(P<0.05),and the ADC values showed a downward trend with the increase in SMS acceleration factors.Conclusion The SMS technique can significantly shorten the scanning time of rectal cancer,and the image quality and ADC values obtained at the optimal value of SMS acceleration factor of 2 are close to those of rs-EPI.

关 键 词：直肠癌 同时多层采集 表观扩散系数 分段读出平面回波成像 

分 类 号：R735.37[医药卫生—肿瘤] R445.2[医药卫生—临床医学]