In this study,
we determine gadolinium deposition and its clinical effect in vivo using normal mice.
Despite high gadolinium deposition in several organs,
we observed no changes in the skin of the mice nor any other clinical sign rising related to the continuous administration of gadolinium solution.
Chelated gadolinium is safe to be administered for MR Imaging.
However,
chelate changes the structure of gadolinium and have more properties than free gadolinium [1,
3,
5,
6].
Previous studies showed that “free” gadolinium will rapidly bind with anion in the environment such as phosphate,
carbonate,
acetate,
ascorbate and hydroxide.
Afterwards,
gadolinium phosphate and gadolinium carbonate are rapidly attached to the surface of human dermal fibroblast [5].
Based on these facts,
gadolinium deposition in the skin is likely to be gadolinium phosphate or gadolinium carbonate.
Gadolinium salts and Gd-DTPA based contrast media are taken and supposed to be cleared in the Hepatobiliary system,
especially Kupffer cells in the liver and macrophage in the spleen [4,
6].
The remaining agents are eliminated via glomerular filtration [6].
This corresponds with our ICP-MS results which explained why the spleen and liver has the highest deposition,
followed by the kidney.
ROI analysis on T1WI has a strikingly different result with ICP-MS measurement.
MRI analysis showed that GdCl3 group has the highest CNR,
whereas ICP-MS showed that Gd-DTPA-BMA group has the highest deposition in the brain.
There are two possible explanations for this result.
First,
previous studies showed when the BBB is broken,
enhanced MR T1W- Images showed many different patterns of enhancement [7,
8].
Hence,
the pattern of deposition is probably different from each sample.
Second,
the ROI analysis was using one slice of the image sequence,
while ICP-MS measurement used the whole cerebrum.
Therefore,
ICP-MS considered more accurate than ROI analysis.
To sum up,
our study corresponds with some of the results of the previous study.
We manage to determine the distribution of gadolinium deposition in several organs of the mice.
Although macrocyclic is the most stable GBCA,
high deposition in the kidney of the Gd-DOTA showed us different insight about the chelate properties of macrocyclic GBCA.
Limitation:
There are several limitations in this study.
First,
we did not measure the exact gadolinium complex that has been deposited in our sample.
Thus,
we could not determine whether chelated GBCA or separated gadolinium complex that deposited in the organs.
Second,
it is difficult to choose the appropriate region of interest as the gadolinium deposition pattern is not the same.
Third,
the different result between CNR and ICP-MS need to be confirmed by measuring gadolinium deposition in the muscle.
Last,
the number of ICP-MS sample may be inadequate to provide a very significant result.
