Grünberg K, Grenacher L, Klauss M
Abteilung Radiologie, Deutsches Krebsforschungszentrum (DKFZ) Heidelberg, Im Neuenheimer Feld 280, Heidelberg, Germany.
Radiologe. 2011 Mar;51(3):186-94. doi: 10.1007/s00117-010-2059-9.
Diffusion-weighted imaging (DWI) has increasingly gained in importance over the last 10 years especially in cancer imaging for differentiation of malignant and benign lesions. Through development of fast magnetic resonance imaging (MRI) sequences DWI is not only applicable in neuroradiology but also in abdominal imaging. As a diagnostic tool of the pancreas DWI enables a differentiation between normal tissue, cancer and chronic pancreatitis. The ADC values (apparent diffusion coefficient, the so-called effective diffusion coefficient) reported in the literature for healthy pancreatic tissue are in the range from 1.49 to 1.9×10(-3) mm(2)/s, for pancreatic cancer in the range from 1.24 to 1.46×10(-3) mm(2)/s and for autoimmune pancreatitis an average ADC value of 1.012×10(-3) mm(2)/s. There are controversial data in the literature concerning the differentiation between chronic pancreatitis and pancreatic cancer. Using DWI-derived IVIM (intravoxel incoherent motion) the parameter f (perfusion fraction) seems to be advantageous but it is important to use several b values. In the literature the mean f value in chronic pancreatitis is around 16%, in pancreatic cancer 8% and in healthy pancreatic tissue around 25%. So far, DWI has not been helpful for differentiating cystic lesions of the pancreas. There are many references with other tumor entities and in animal models which indicate that there is a possible benefit of DWI in monitoring therapy of pancreatic cancer but so far no original work has been published.
在过去十年中，扩散加权成像（DWI）的重要性日益凸显，尤其在癌症成像中用于鉴别恶性和良性病变。随着快速磁共振成像（MRI）序列的发展，DWI不仅适用于神经放射学，也适用于腹部成像。作为胰腺的诊断工具，DWI能够区分正常组织、癌症和慢性胰腺炎。文献报道的健康胰腺组织的表观扩散系数（ADC值，即所谓的有效扩散系数）范围为1.49至1.9×10⁻³mm²/s，胰腺癌的ADC值范围为1.24至1.46×10⁻³mm²/s，自身免疫性胰腺炎的平均ADC值为1.012×10⁻³mm²/s。关于慢性胰腺炎和胰腺癌的鉴别，文献中的数据存在争议。使用基于DWI的体素内不相干运动（IVIM），参数f（灌注分数）似乎具有优势，但使用多个b值很重要。文献中慢性胰腺炎的平均f值约为16%，胰腺癌为8%，健康胰腺组织约为25%。到目前为止，DWI对胰腺囊性病变的鉴别没有帮助。有许多关于其他肿瘤实体和动物模型的参考文献表明，DWI在监测胰腺癌治疗方面可能有益，但迄今为止尚未发表原创性研究。
