Tweedle M F
Bracco Research USA, 305 College Rd. East, Princeton, NJ 08540, USA.
Eur Radiol. 1997;7 Suppl 5:225-30. doi: 10.1007/pl00006897.
The four gadolinium chelates currently in clinical use as magnetic resonance imaging (MRI) contrast agents differ in two structural features: linear vs. macrocyclic cores, and ionic vs. nonionic charge types. While all are equivalent in relaxation effectiveness, the nonionic molecules have lower osmolality and viscosity and may be formulated safely at greater concentrations, and delivered confidently at greater doses and as a faster bolus. The macrocyclic molecules are more stable and show less tendency to dissociate free Gd. ProHance was conceived well over a decade ago, based upon a unique structure. It was first marketed in the USA in 1992, and was the first nonionic agent. It remains today still the only commercial MRI agent that is both macrocyclic and nonionic. To date it has been used safely in over a million patients.
目前临床上用作磁共振成像（MRI）造影剂的四种钆螯合物在两个结构特征上有所不同：线性与大环核心，以及离子型与非离子型电荷类型。虽然它们在弛豫效果上相当，但非离子型分子具有较低的渗透压和粘度，可以在更高浓度下安全配制，并能以更大剂量和更快的推注速度放心给药。大环分子更稳定，游离钆解离的倾向较小。普乐显（ProHance）是基于独特结构在十多年前构思出来的。它于1992年在美国首次上市，是首个非离子型造影剂。如今它仍然是唯一一种兼具大环和非离子特性的商用MRI造影剂。迄今为止，它已在超过100万名患者中安全使用。
