背景抑制磁共振弥散成像(D WIBS)技术在肝脏局灶性占位性病变中的初步应用

目的:探讨背景抑制磁共振弥散成像(DWIBS)技术在肝脏局灶性占位性病变中的应用价值。方法:回顾性分析肝脏局灶性占位性病灶25例49个。其中肝细胞癌9例12灶,肝转移瘤6例18灶,肝囊肿7例16灶,肝血管瘤3例3灶的背景抑制磁共振弥散成像(b=600s/mm2),测量各病灶的表观弥散系数(ADC)值并进行比较,利用3D-MIP重建及黑白翻转技术,观察病变显示效果。结果:在b=600s/mm2的图像中,肝脏恶性肿瘤多表现为高信号;肝脏良、恶性肿瘤间差异具有统计学意义(P<0.05);肝细胞癌与肝转移瘤组间、肝囊肿与肝血管瘤组间无统计学差异(P>0.05)。背景抑制的DWI经MIP重建及黑白翻转技术,病变周围组织信号被抑制,得到类PET图像,25例49个病灶,均清晰显示。结论:背景抑制磁共振弥散加权成像在显示病灶方面有一定优势;应用DWI结合ADC值对于肝脏良、恶性占位病变有一定鉴别价值。

Preliminary application of diffusion weighted MR imaging with background suppression in hepatic local masses

Objective:To evaluate diffusion-weighted MR imaging with background suppression in hepatic local masses.Methods: The diffusion-weighted imaging by background suppression(b=600s/mm2) in 25 patients(49 lesions) with hepatic local masses were retrospectively analyzed(12 hepatocellular carcinoma,18 hepatic metastases,16 hepatic cysts,3 hepatic hemangioma).Apparent diffusion coefficient(ADC) of all the lesions were measured and compared.The lesions were displayed by rebuilding with 3D-MIP and the technique with reverse black and white.Results: Most of the malignant tumors were hyperintensity on DWI(b=600s/mm~2).The difference was statistically significant between hepatic benign tumor and hepatic malignant tumor(P<0.05);The difference was not statistically significant between hepatocellular carcinoma and hepatic metastases,hepatic cyst and hemangioma(P>0.05). Twenty-five patients with 49 lesions were displayed clearly in diffusion-weighted MR imaging alike PET with background suppression,where the sign of the tissue around the lesions be inhibited,rebuilded by 3D-MIP and the technique with reverse black and white.Conclusion: Diffusion-weighted MR imaging with background suppression take the advantages of easily identifying the focus,and DWI combined with ADC values may be certain help in differentiating between hepatic benign and malignant tumor.