The optimal b value in DWI of stomach neoplasm: a preliminary study
XU Chuan-jun1, LIU Lin-xiang2, LI Xiao-dong3, WANG Jin-liang4, JIANG Xue-mei1, ZHU Xi-qi1
1.The Second Affiliated Hospital of Southeast University, Nanjing 210003, China;2.College of Radiology, Taishan University of Medical Science, Taian Shandong 271016, China;3.Department of Radiology, General Hospital, Tianjin Medical University, Tianjin 300052, China;4.Department of Medical Imaging, Linyi People’s Hospital, Linyi Shandong 276000, China
Abstract:Objective: To choose the optimal b value in diffusion weighted imaging of stomach neoplasm. Material and Method: Thirty-two cases were proved to be stomach neoplasms by operation and pathology. Four DWI sequences were performed with different b values, including 400s/mm2, 600s/mm2, 800s/mm2, 1000s/mm2. The ADC value of different stomach neoplasm and free water in gastric lumen were measured. SIR of DWI with different b value was evaluated and compared. Then using image analysis software, the density of cells in pathologic specimens were calculated. Finally, use of statistical analysis software, correlation between the density of cell and ADC of stomach tumor under different b value was calculated. According to correlation of the above-mentioned calculations and SIR(ratio water-background noise), optimal b value was determined. Result: When b value was 400s/mm2, 600s/mm2, 800s/mm2, 1000s/mm2, correlation between the density of cell and ADC of stomach tumor under different b value was: -0.3458, -0.3789, -0.5865, -0.5231 respectively. There was significant difference between different b value(P<0.05). The SIR of different b value was: 2.036, 1.541, 1.148, 1.109 respectively(F=40.12, P<0.05). When b value was 400s/mm2, 600s/mm2, 800s/mm2, there were significant difference between them (P<0.05). When b value was 800s/mm2, 1000s/mm2, SIR approximate 1, there were significant difference between them(P<0.05). Conclusion: Diffusion weighted imaging for diagnosing gastric tumor is feasible, the best optimal b value is 800s/mm2. as b value as 800s/mm2, correlation between the density of cell and ADC of stomach tumor was the best, and SIR approximate 1. We can approximately think T2 influence was eliminated, and it can reflect the real situation of water molecules diffusion.
许传军;刘林祥;李晓东;王金亮;蒋学美;朱西琪. 胃肿瘤MR扩散加权成像中扩散敏感因子选择的初步研究[J]. , 2010, 21(9): 625-628.
XU Chuan-jun;LIU Lin-xiang;LI Xiao-dong;WANG Jin-liang;JIANG Xue-mei;ZHU Xi-qi. The optimal b value in DWI of stomach neoplasm: a preliminary study. , 2010, 21(9): 625-628.