On May 5, 2015, another gadolinium-related study by Kanda et al was published online ahead of print in Radiology. The study, Gadolinium-based Contrast Agent Accumulates in the Brain Even in Subjects without Severe Renal Dysfunction: Evaluation of Autopsy Brain Specimens with Inductively Coupled Plasma Mass Spectroscopy, evaluated brain tissues obtained at autopsy in five randomly selected subjects that had received a gadolinium-based contrast agent (GBCA) at least twice, and five subjects that had no history of GBCA administration. The GBCAs involved were the linear agents Magnevist and Omniscan, and the macrocyclic agent ProHance. Gadolinium was detected in all specimens in the GBCA group, and was found at significantly higher concentrations in the dentate nucleus (DN) and globus pallidus (GP) than the other regions tested. The estimated glomerular filtration rates (eGFRs) of the five subjects in the GBCA group were 47.5, 49.5, 60, 65.5, and 83.4. Kanda and his colleagues concluded that even in subjects without severe renal disease, GBCA administration causes gadolinium accumulation in the brain, especially in the dentate nucleus and globus pallidus.
All five subjects in the GBCA group received Magnevist; three had received only Magnevist for their 2, 3 or 4 GBCA doses. One subject had received 3 GBCA doses: Magnevist (1), Omniscan (1), and ProHance (1). One other subject had received 4 GBCA doses: Magnevist (3) plus ProHance (1).
Samples of the dentate nucleus (DN), inner segment of the globus pallidus (GP), cerebellar white matter, frontal lobe cortex, and frontal lobe white matter, were obtained from autopsy specimens of the 5 subjects in the GBCA group and the 5 subjects in the non-GBCA group. Inductively coupled plasma mass spectroscopy (ICP-MS) was used to analyze gadolinium concentration in the formalin-fixed brain tissue specimens. Higher gadolinium concentration was seen in the DN and GP than in the other regions of the brain.
“Because gadolinium is not an essential element in nature, its presence in the body is almost certainly due to GBCA administration,” Kanda and his colleagues said.
The recent study by Kanda et al joins a growing body of research that indicates that gadolinium-based contrast agents may not work exactly as many thought they did. The free gadolinium ion is toxic and it remains to be seen how much retained gadolinium the human body can tolerate.
Kanda, T., Fukusato, T., Matsuda, M., Toyoda, K., Oba, H., Kotoku, J., … Furui, S. (2015). Gadolinium-based Contrast Agent Accumulates in the Brain Even in Subjects without Severe Renal Dysfunction: Evaluation of Autopsy Brain Specimens with Inductively Coupled Plasma Mass Spectroscopy. Radiology, 142690. http://doi.org/10.1148/radiol.2015142690