磁共振DWI并3D-VIBE序列对胰头慢性胰腺炎与胰头癌的鉴别诊断

目的探讨磁共振DW（I弥散加权成像）并3D-VIBE（三维梯度回波容积内插法）序列在胰头慢性胰腺炎与胰头癌鉴别诊断中的应用价值。方法 17例经临床、手术和病理证实的胰头疾病患者（胰头慢性胰腺炎4例,胰头癌13例）,分别行常规MRI检查、DWI、3D-VIBE序列平扫及动态增强扫描,对所获得的图像资料主要观测以下内容：肿块形态学特点,DWI肿块信号特征,肿块多期强化特征,胰管、胆管的改变,胰周血管显示情况,胰周器官受累情况及有无远处转移病灶等。结果 DWI肿块的信号特征：三组不同高b值（400、600、800s/mm3）的图像均显示胰头慢性胰腺炎呈较高信号,且信号近似于胰体、尾组织信号;胰头癌肿块信号明显高于正常胰腺组织信号者。3D-VIBE序列胰腺肿块强化特征分析结果：胰头慢性胰腺炎组中胰头部肿块动脉期几乎无强化,其强化程度明显低于正常胰腺组织,门脉期、延迟期肿块逐渐强化;而胰头癌组中胰头部肿块动脉期强化程度低于正常胰腺组织,门脉期、延迟期肿块强化效应逐渐减退。结论 DWI结合3D-VIBE动态增强扫描技术能较全面的显示胰头肿块的影像学特征,有助于胰头慢性胰腺炎与胰头癌的鉴别诊断。

The feasibility of combined application of MR DWI and 3D-VIBE sequence for differentiating chronic pancreatic head inflammation from pancreatic head carcinoma

Objective To evaluate the feasibility of combined application of MR DWI and 3D-VIBE sequence for differentiating chronic pancreatic head inflammation（CPHI） from pancreatic head carcinoma（PHC）.Methods Seventeen patients with clinically,surgically and pathologically proved pancreatic head masses which comprised PHC（n=13） and CPHI（n=4） underwent conventional MRI,MR DWI and 3D-VIBE sequence scans before and after Gd-DTPA injection.Based on imaging data acquired from different MRI sequences,the follwing signs such as morphologic features of the pancreatic head masses,morphologic changes of the pancreatic ducts and bile ducts,involvement of peripancreatic blood vessels,local invasion of the neighbor organs,existence or absence of the distant metastases,and the sig nal characteristics of CPHI vs PHC were emphatically observed and comparatively analyzed.Results The signal characteristics of CPHI on DWI（b=400,600,800 s/mm3） were higher signals than that of normal pancreatic tissue and were approximate to that of pancreatic body and tail,while those of PHC were obviously higher signals than normal pancreatic tissue.3D-VIBE sequence showed that CPHI was scarcely enhanced during arterial phase and then was gradually enhanced during venous and delayed phase,while the signal intensity of PHC was lower than that of normal panereatic tissue during arterial phase and then was gradually reduced during venous and delayed phase.Conclusion Dynamic-enhanced scans of MR DWI combined with 3D-VIBE sequence can completely show the imaging features of CPHI vs PHC so that it is feasible to differentiate the both.