Fobbe F, Wacker F, Wagner S
Auguste-Viktoria-Krankenhaus Berlin, Department of Radiology, Germany.
Eur Radiol. 1996;6(2):224-9. doi: 10.1007/BF00181155.
Iodine-containing contrast agents are currently used for angiography. However, due to the relatively low atomic number of iodine, imaging must be performed with a relatively low tube voltage. Gadolinium has been used for several years as a contrast agent in MRI with low adverse side effects. This substance has a higher atomic number as compared with iodine. We investigated whether the use of a gadolinium-containing contrast agent with a higher tube voltage reduces the radiation exposure in angiography, and how the image quality compares with the previous technique. A total of 15 patients were examined with either a survey angiography or a selective angiography. In all patients angiography was performed with an iodine-containing contrast agent with a tube voltage of 75 kV. Then gadolinium-containing contrast agent was administered immediately with a tube voltage of 110 kV. Radiation exposure and image quality were compared. On average, a dose reduction factor of 3.57 times was achieved by using 110 instead of 75 kV. However, the image quality was poorer in the majority of cases as compared with the images taken with iodine as a contrast agent and a tube voltage of 75 kV. The poorer image quality is caused by the relative low concentration (0.5 M) of the used gadolinium solution. A 1 M solution is currently tested for market approval and would probably solve this problem.
含碘造影剂目前用于血管造影。然而，由于碘的原子序数相对较低，成像必须在相对较低的管电压下进行。钆作为一种副作用较小的造影剂已在磁共振成像（MRI）中使用多年。与碘相比，这种物质的原子序数更高。我们研究了使用含钆造影剂并提高管电压是否能减少血管造影中的辐射暴露，以及图像质量与先前技术相比如何。共有15名患者接受了概况血管造影或选择性血管造影检查。所有患者均使用含碘造影剂，管电压为75千伏进行血管造影。然后立即使用管电压为110千伏的含钆造影剂。对辐射暴露和图像质量进行了比较。平均而言，使用110千伏而非75千伏可使剂量降低系数达到3.57倍。然而，与使用碘作为造影剂且管电压为75千伏拍摄的图像相比，大多数情况下图像质量较差。图像质量较差是由于所用钆溶液的相对低浓度（0.5摩尔/升）所致。目前正在对一种1摩尔/升的溶液进行市场批准测试，可能会解决这个问题。
