3.0 T MR胃癌患者IVIM-DWI序列参数优化的初步研究

目的 探讨3.0 T MR胃癌患者体素内不相干运动扩散加权成像(intravoxel incoherent motion diffusion weighted imaging,IVIM-DWI)中扫描参数的优化选择.材料与方法 前瞻性收集我院自2018年12月至2019年10月经胃镜病理证实的胃癌患者40例进行术前MR...

The preliminary study on the parameter optimization of IVIM-DWI pulse sequence in gastric cancer patients with 3.0 T MR

Objective:To investigate the optimal selection of scan parameters in intravoxel incoherent motion diffusion weighted imaging(IVIM-DWI)gastric cancer patients with 3.0 T MR.Materials and Methods:Forty patients with gastric cancer confirmed by gastroscopy pathology from December 2018 to October 2019 in our hospital were collected prospectively for preoperative MRI examination.Patients were divided into A,B two groups with the random digital table method.Group A increased the number of signal average and extended repetition time(TR)and echo time(TE)appropriately.Group B reduced the number of signal average and reduced the TR and TE.The other parameters of the two groups are the same.The scanning time of A,B two groups was 14 min and 7 min 12 s respectively.The signal-to-noise ratio(SNR),contrast noise ratio(CNR),and the ADCslow,ADCfast,f value of the lesion were measured for each patient's IVIM-DWI sequence(b values equal to 1200 t)images.The differences of SNR,CNR,ADCslow,ADCfast,f value were compared by independent sample t test,and the image quality was evaluated subjectively by double-blind method.Results:The SNR values of A and B group were 56.60±34.64,53.50±20.21.And the CNR values were 44.95±18.52,41.38±31.72,and the ADCslow values were 0.635±0.274,0.818±0.305,the ADCfast values were 6.100±1.075,6.471±1.549,the f values were 0.419±0.184,0.402±0.193.There was no significant difference in SNR,CNR,ADCslow,ADCfast,f values between A and B groups(P>0.05).The subjective scores of images between A and B groups were statistically significant(P<0.05).Conclusions:Not only the scanning time is obviously shortened,but also the image quality can meet the diagnostic requirements by reducing the number of signal average and shortening the TR,TE scanning scheme appropriately.Thus improve the feasibility of MR examination for gastric cancer patients.