磁共振背景抑制弥散成像对肝占位性病灶诊断价值的初步研究

目的:初步探讨背景抑制弥散成像(DWIBS)技术对肝占位性病灶的诊断价值。方法:对28例患者的46个肝占位性病灶进行回顾性分析,其中肝细胞癌10例13灶,肝转移瘤7例14灶,肝血管瘤4例7灶,肝囊肿7例12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)值并比较,通过背景抑制的WDI经MIP重建及黑白反转技术制作局部类PET图像,观察病灶显示效果。结果:在b=600s/mm2的图像中,肝内良性病变ADC值明显高于恶性病变,以1.6×10-3 mm2/s作为良恶性病变ADC值的界限,敏感性和特异性均>90%;原发性肝癌、肝转移瘤、肝血管瘤、肝囊肿的ADC值呈递增趋势;局部类PET图像,28例46个肝占位性病灶均显示清晰。结论:背景抑制弥散成像并测量病灶的ADC值对肝占位性病灶良恶性的判断有一定的临床应用价值。

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

Objective：To study the diagnostic value of diffusion weighted MR imaging with background suppression in he- patic focal masses. Methods：The diffussion- weighted imaging with background suppression （h= 600 s/ram2） in 28 pa- tients （46 lessions） with hepatic focal masses were retrospectively analyzed （13 hepatocellular carcinoma, 14 hepatic metas- tases,7 hepatic hemangioma, 12 hepatic cysts）, Apparent diffusion coefficient （ADC） of rebuilding with 3D-MIP and all the technique with reverse black and white were performed were performed. Results： ADC values of benign lessions were higher than those of malignant ones and 1.6 ）〈 10-~ mm2/s can be set as the criteria for benign lessions versus malignamey with both sensitivity and specificity higher than 90 %. ADC decreased in HCC and metastasis, while that of hemangioma and hepatic cyst increasd in turn. 28 patients with 46 lessions were displayed clearly in diffusion-weighted MR imaging a- like PET. Conclusion： MR DWIBS combined with ADC values may be certain helpful in differentiating benign and malig- nant hepatic tumors.