Effect of Image Quality of Gd-EOB-DTPA Enhanced MRI by Increasing Flip Angle / 中国医学影像学杂志

ABSTRACT

Purpose It has been demonstrated that hepatocytes uptake of Gd-EOB-DTPA obviously decreased,which would result in decreased liver-to-lesion contrast.Therefore,this study was to evaluate the potential of increasing flip angle to improve the image quality of Gd-EOB-DTPA enhanced MR.Materials and Methods A total of 114 patients with focal liver lesions (FLLs),who underwent Gd-EOB-DTPA-enhanced MR of the liver,were enrolled in this retrospective study.39 patients were noncirrhotic group,36 patients were Child-Pugh A group,23 patients were Child-Pugh B group,and 16 patients were ChildPugh C group.Tl-weighted with fat suppression volume interpolated breath hold examination (VIBE) sequence was acquired before and 5 min,10 min,15 min,20 min after the administration of Gd-EOB-DTPA with both conventional low FA (9 °) and high FA (27 °) protocols separately.Signal to noise ratio (SNR),liver to lesion contrast (LLC),the liver to lesion SI ratio (LLSIR) were calculated and analyzed between low and high FA protocol images in each group and each scan time.Results The LLC and LLSIR on GdEOB-DTPA-enhanced MR images using a high FA (27 °) protocol were significantly higher in comparison with the conventional low FA (9°).In Child B group and Child C group,the LLC and the LLSIR with low FA significantly reduced during 15～20 min after contrast agent injection,however with high FA,the value of LLC and LLSIR tended to be horizontal.Conclusion A high FA protocol in comparison with the conventional 9° FA can obviously improve the image quality,which is reliable for liver lesion depiction on GdEOB-DTPA-enhanced MR images,especially to those with severe liver cirrhosis.