胰腺癌的CT与MR诊断新进展

Diagnosis of Pancreatic CarcinomaUsing CT and MR Diagnostic Imaging Modalitis

近十年中胰腺的影像学检查，由于技术的飞跃发展，发生了显著的变化。高分辨率ＣＴ 及磁共振成像（ ＭＲＩ） 的发展均为胰腺的检查诊断的进展作了贡献。胰腺癌的ＣＴ：胰腺癌的ＣＴ 诊断标准是：１ ．胰腺肿块。２ ．胰管和／ 或胆管扩张。３ ．局部淋巴结增大。４ ．血管（ 下腔静脉、腹腔动脉和／ 或肠系膜上动脉） 周围脂肪内肿瘤浸润。５ ．腹水。６ ．肝和远处转移。胰腺癌ＣＴ 的新进展：１ ．螺旋ＣＴ 增强扫描：是胰腺癌ＣＴ 的新发展，能良好显示强化的胰实质及血管结构改善了对小癌瘤的检出，且能准确地评价胰周血管，从而准确地预测胰腺癌的可切除性。２ ．ＣＴ 导引下细针穿刺活检，可减少确定诊断的时间。胰腺癌的 ＭＲＩ：胰腺的ＭＲＩ 检查技术不很成熟，尚在发展中。常规横断面 ＭＲＩ 可以显示胰腺实质，胰周血管及上腹部邻近实质器官的解剖结构。ＭＲＩ 的新进展：（１） ＭＲ 胰胆管造影：它无需造影剂，安全、无创伤、诊断正确性高，是极有效的影像学检查手段，可提供临床有价值的诊断信息。此技术可作为传统的影像学检查的补充，在某种程度上有可能替代经内窥镜逆行胰胆管造影（ＥＲＣＰ） 。（２） ＭＲ 导引下经皮穿刺活检：此技术在国际上刚开展，正在探索中，也应用于腹部，?

In the present stude, patients with pancreatic carcinoma were examined using US (ultrasonography), CT(computed tomography), MRI(magnetic resonance imaging), ERCP(endoscopic retrograded cholangiopancreatography). US is first employed. If US findings indicate the presentce of pancreatic carcinoma. CT and MR imaging are performed for staging the carcinoma, ERCP follow. All of these were examined to evaluate the characteristics of pancreatic carcinomas. CT is the preferred investigative technique because when used with contrast enhancement, it displays in detail not only the entire pancreas and surrouding tissues but also other structure likely to be affected by the pancreatic tumor .Critical factors in staging include the presence of adjacent organ invasion, local arterial encasement or invasion (celiac axis and its branches and superior mesenteric artery), local venous encasement or invasion(superior mesenterie vein, portal vein, inferior mesenteric vein, or splenic vein), and peri-pancreatic lymphadenopathy, In today's, for staging pancreatic carcionma with advantages in helical CT technology. The increases speed allows for several important advantages over conventional CT. Investigation is also under way to determine the utility of MRI, which has considerable potential because it combines evalution of the pancreas and peripancreatic tissue with examination of the liver, as well as assessment of the abdominal vasculature with MRA. MR cholangiopancreatography(MRCP) is an exiting new application of MR imaging that combines the advantages of projectional and cross-sectional imaging techniques. The technique is capable of depicting the pancreatic-bile duct. That requires neither the use contrast agent nor any biliary intervention and high accuracy in the diagnosis of pancreatic-bile disease.