3.0T磁共振扩散加权成像的b值在直肠癌检查中的选择

SELECTION OF B VALUE ON DWI IN RECTAL CANCER EXAMINATION USING A 3.0T MR SCANNER

目的探讨DWI检测直肠癌病灶的最佳条件。方法选取27例直肠癌患者,术前行MRI常规扫描和多b值DWI检查。分析评估DWI图像质量及SNR。结果直肠癌病变T1WI呈等低信号,在T2WI及T2WI SPAIR呈稍高信号,在DWI图像稍高信号或中等高信号。随着b值的增大,DWI图像质量评分及SNR值均呈上抛物线趋势(F=60.45,5.82;P<0.01),b=800 s/mm^2时图像质量评分及SNR值最高。结论3.0T DWI中b=800 s/mm^2是检测直肠癌的较好条件。

Objective To explore the best conditions for detecting DWI in rectal cancer.Methods Twenty-seven patients with rectal cancer were selected and examined with routine MRI scans and multiple b-value DWI examinations before surgery.The DWI image quality and SNR were analyzed and evaluated.Results Rectal cancer lesions showed a low signal at T1WI,a slightly high signal at T2WI and T2WI SPAIR,and a slightly high signal or medium high signal at DWI.With the increase of b value,the DWI image quality score and SNR value both show a parabolic trend(F=60.45,5.82;P<0.01).The image quality score and SNR value are highest at b=800 s/mm^2.Conclusion b=800 s/mm^2 in 3.0T DWI is a better condition for detecting rectal cancer.