Comparison of iShim-DWI and SS-EPI in MR of Space-Occupying Lesion of the Lung
Objective To compare the difference in imaging quality between integrated shimming diffusion weighted imaging(iShim-DWI)and single-shot echo planar imaging(SS-EPI)applied to MR examination of lung occupying lesions.Methods MR images of patients with CT-confirmed space-occupying lesions of the lung between September 2017 and March 2023 were prospectively collected.All patients performed SS-EPI,iShim-DWI and T2WI sequences using 3.0 T MRI.T2WI were used as a reference and two radiologists scored the overall quality of two DWI using a five-point scale.Kappa test was used to evaluate the consistency of two radiologists'scores,Wilcoxon test was used to compare the differences in image quality between the two DWI sequences.Two radiologists measured quantitative parameters of the lesion together,calculating the signal-to-noise ratio(SNR),contrast-to-noise ratio(CNR)and genmetric distortion ration(GDR)of the anterior and posterior(AP)and left and right(RL)of lesion,and measuring the lesion's ADC value.Results A total of 56 patients with space-occupying lesions of the lung were collected,including 23 cases of lung cancer,33 cases of metastases.The consistency of two radiologists on the images quality scored was very well(Kappa＞0.75),and the differences between the image quality scores of both sequences were statistically significant(P＜0.001).The SNR and CNR measured by iShim-DWI and SS-EPI were 23.683、39.803 and 15.525、21.261,respectively,and the differences were statistically significant(P＜0.001).The GDR of lesions'AP and RL measured by iShim-DWI and SS-EPI were 6.914、6.879 and 27.827、25.859,respectively,the GDR of iShim-DWI was significantly lower than SS-EPI(P＜0.001).The mean ADC of the lesions measured by the two sequences were 1.097 × 10-3,1.105 ×10-3 mm2·s-1,respectively,and the difference was not statistically significant(P＞0.05).Conclusion Compared with SS-EPI,iShim-DWI could significantly improve image quality of DWI sequences in space-occupying lesion of the lung.
space-occupying lesion of the lungDWIimage qualityiShim-DWISS-EPI
万方数据
维普
