From the Department of MR and CT Contrast Media Research, Bayer, Muellerstr 178, Berlin 13353, Germany (G.J., T.F., J.L., H.P.); Institute of Physiology, Charité, Berlin, Germany (J.B.); and Forschungszentrum Juelich, Juelich, Germany (V.N.).
Radiology. 2019 Feb;290(2):340-348. doi: 10.1148/radiol.2018180135. Epub 2018 Nov 13.
Purpose To investigate the long-term course of MRI signal intensity (SI) changes and the presence of gadolinium in the rat brain during a 1-year period after multiple administrations of gadolinium-based contrast agents (GBCAs). Materials and Methods Rats received a linear GBCA (gadodiamide, gadopentetate dimeglumine, gadobenate dimeglumine), a macrocyclic GBCA (gadobutrol, gadoterate meglumine, gadoteridol), or saline. Animals received eight injections over 2 weeks (1.8 mmol/kg per injection). Brain MRI and gadolinium measurements were performed with inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation ICP-MS 5, 26, and 52 weeks after administration. Results Animals that received linear GBCAs showed higher deep cerebellar nuclei (DCN)-to-brainstem SI ratios compared with the saline group (P < .001 at all time points). After 1 year, mean gadolinium concentrations in the cerebellum were 3.38 nmol/g (gadodiamide), 2.13 nmol/g (gadopentetate dimeglumine), and 1.91 nmol/g (gadobenate dimeglumine). For linear agents, laser ablation ICP-MS revealed gadolinium depositions in the cerebellar nuclei. For macrocyclic GBCAs, the DCN-to-brainstem SI ratios did not significantly differ from those in the saline group (P > .42) and the cerebellar gadolinium concentrations decreased between weeks 5 and 52, reaching 0.08 nmol/g (gadobutrol), 0.04 nmol/g (gadoterate meglumine), and 0.07 nmol/g (gadoteridol). The respective laser ablation ICP-MS analysis showed no gadolinium depositions. Conclusion Increased signal intensity in the deep cerebellar nuclei of rats persists for at least 1 year after administration of linear gadolinium-based contrast agents (GBCAs), in line with persistent brain gadolinium concentrations with no elimination after the initial 5-week period. The animals that received macrocyclic GBCAs showed an ongoing elimination of gadolinium from the brain during the entire observation period. © RSNA, 2018.
目的 探究在多次给予基于钆的造影剂（GBCA）后，大鼠脑内 MRI 信号强度（SI）改变及钆存在的长期病程。
材料与方法 大鼠接受线性 GBCA（钆喷酸葡胺、钆喷替酸葡甲胺、钆贝葡胺）、大环 GBCA（钆布醇、钆特酸葡胺、钆特醇）或生理盐水治疗。动物在 2 周内接受 8 次注射（每次 1.8 mmol/kg）。在给药后 5、26 和 52 周进行脑 MRI 和钆测量，采用电感耦合等离子体质谱法（ICP-MS）和激光烧蚀 ICP-MS。
结果 接受线性 GBCA 的动物与生理盐水组相比，深部小脑核（DCN）-脑干 SI 比值更高（所有时间点均 <.001）。1 年后，小脑的平均钆浓度分别为 3.38 nmol/g（钆喷酸葡胺）、2.13 nmol/g（钆喷替酸葡甲胺）和 1.91 nmol/g（钆贝葡胺）。对于线性造影剂，激光烧蚀 ICP-MS 显示在小脑核中存在钆沉积。对于大环 GBCA，DCN-脑干 SI 比值与生理盐水组相比无显著差异（P >.42），且小脑内的钆浓度在 5 周至 52 周之间下降，分别达到 0.08 nmol/g（钆布醇）、0.04 nmol/g（钆特酸葡胺）和 0.07 nmol/g（钆特醇）。相应的激光烧蚀 ICP-MS 分析未显示钆沉积。
结论 大鼠深部小脑核的信号强度在接受线性 GBCA 后至少持续 1 年，与最初 5 周后无消除情况下持续的脑内钆浓度一致。接受大环 GBCA 的动物在整个观察期间表现出脑内钆的持续消除。
© RSNA，2018。
