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:CT 是目前胰腺的最主要影像检查手段.胃和十二指肠的满意充盈、薄层扫描以及静脉内对比剂的正确使用,即增强后不同时期扫描是CT 在胰腺检查技术中的三个关健要素.随着螺旋CT 越来越多地应用于临床,这些要素能够得到更好地满足,也使CT 血管造影(CTA) 成为可能.MR 更多的是作为病人在碘剂过敏或CT 未能明确胰腺病变时的检查手段,MR 的一些新的技术使成像时间大大缩短,减少了腹部检查中的伪影,使其在发现胰腺病变及确定特征上的作用得到加强.胰腺最重要的病理类型是导管腺癌,以浸润生长的方式向周围扩展.CT 上首先表现为腺体的局部增粗或肿块,引起胰腺外形改变或密度异常不均,静脉注射对比剂后腺体实质增强而肿瘤则表现为不均匀的低密度,由于胰腺癌的70 % 发生在头颈部,使得胰胆管的扩张比例相当高,典型时出现“双管征”,MRCP 用无创的方法可提供很好的胰管和胆管图像.能很好显示胰胆管的梗阻、扩张及其它病变.胰腺癌时周围血管的受侵及包裹是非常重要的征象,胰体癌时更多见,依次以SMA,CA,PV 和腹主动脉.胰腺癌的其它影像表现包括对周围组织器官的侵及和远处的血行转移.这些都是胰腺癌不可切除的指征,也是影像学在诊断中应该起的作用.“,”CT scan is still the main type of examination for pancreatic cancer. There are three key points of CT scan technique for pancreas: satisfactory filling of stomach and duodenum with oral contrast, 3-5mm of thin slice for CT scanning and correct using intravenous contrast medium, which means take biphase or triphase postcontrast scanning for pancreas. According spiral CT has more dramatic application on clinical scanning , these key points can be done much better and CT Angiography is also become possibly. Comparing with CT, MRI is uauslly employed as an auxiliary examination for pancreas, especially the patient has allergy to iodine contrast and could\'t find any definite lesion by CT even has been suspected abnormality by clinic. In recent years, new MR techniques have increased the role of MRI to detect and characterize pancreatic tumor by shortening scan time and reducing motion artifact.The most common pathological type pf the pancreatic cancer is ductal adenocarcinoma which infiltrating and extending into the parapancreatic tissue. The local solid mass on CT is the primary sign. Mass can be detected by contour alteration and difference in attenuation. After a bolus injection of contrast medium, the normal pancreatic paraenchyma is enhanced homogeneosly. While the tumor appear as hypotenuse especially during the arterial phase. As the prevalent location of pancreatic carcinoma on the head, it causes high rate of obstruction of the CBD and pancreatic duct, especially appears as “double duct sign”. MRCP has permitted non-invasive demonstration of the biliary and pancreatic ducts. It can assess ductal obstruction, dilatation and many other ductal abnormalities. Detection of vascular encroachment by pancreatic cancer is very important, such as superior mesenteric vein, celiac trunk, portal vein and abdominal artery. The other imaging finding includs invasion of the parapncreatic organ and metastasis. these usually indicate unresectability.