MR diffusion weighted imaging of gastric cancer:b-value determination and comparison with routine sequences
- VernacularTitle:胃癌MR扩散加权成像扩散敏感因子的选择及其与常规序列的对照研究
- Author:
Xiao-Peng ZHANG
;
Lei TANG
;
Ying-Shi SUN
;
Jie LI
;
Kun CAO
;
- Publication Type:Journal Article
- Keywords:
Stomach neoplasms;
Magnetic resonance imaging;
Comparative study
- From:
Chinese Journal of Radiology
2000;0(12):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To choose the optimal b-values for the DWI of gastric cancer(GC),and investigate the value of DWI in the diagnosis of GCs.Methods MRI examinations(T_1WI,T_2WI,and DWI)were performed on 31 patients with gastric cancer.Three diffusion-weighted sequences were designed with different b values,including 300 s/mm~2(low),600 s/mm~2(intermediate),and 1000 s/mm~2(high). Free water grade was used to evaluate the suppression of content in gastric lumen.Background contrast grade was used to evaluate the discriminating ability of different sequences between GC and nearby tissues.The ADCs of GCs,nearby gastric wall region,and free water in gastric lumen were measured.SNRc_(Ca),CNR_(Ca-Gw) and SIRc_(Ca-Gw)of high b-value DWI and routine MRI sequences were evaluated and compared.Results The signal intensity of free water in gastric lumen decreased as b-value increased,and the SIR were 8.11? 0.77(b=300 s/mm~2),2.70?0.35(b =600 s/mm~2),and 1.13?0.22(b=1000 s/mm~2)(F= 55.368,P
