Kettritz U, Semelka R C
Department of Radiology, University of North Carolina at Chapel Hill, USA.
Magn Reson Imaging Clin N Am. 1996 Feb;4(1):87-100.
Recent MR techniques such as breath-hold imaging, fat suppression, and dynamic imaging after intravenous administration of gadolinium chelates have reduced artifacts in the abdomen, resulting in an increased role of MR imaging in the evaluation of pancreatic disease. The extracellular contrast agent gadolinium chelate has been shown to enhance normal pancreatic tissue in a homogeneous fashion. Contrast between normal pancreatic tissue and tumor tissue on T1-weighted images may be improved after administration of gadolinium. Because of the lesser vascularization of pancreatic ductal cancers as compared to the normal glandular tissue, the differences in signal intensity are often greatest in the capillary phase immediately after contrast administration. In addition, the hypervascular nature of islet cell tumors, results in good definition of primary tumor and liver metastases on immediate post-gadolinium images.
近期的磁共振(MR)技术,如屏气成像、脂肪抑制以及静脉注射钆螯合物后的动态成像,已减少了腹部的伪影,使得MR成像在胰腺疾病评估中的作用有所增强。细胞外造影剂钆螯合物已被证明能以均匀的方式增强正常胰腺组织。注射钆后,T1加权图像上正常胰腺组织与肿瘤组织之间的对比度可能会得到改善。由于胰腺导管癌的血管化程度低于正常腺组织,信号强度差异通常在注射造影剂后的毛细血管期最为显著。此外,胰岛细胞瘤的高血管特性使得在注射钆后的即刻图像上能很好地显示原发肿瘤和肝转移灶。