MR imaging differentiation of Fe2+ and Fe3+ based on relaxation and magnetic susceptibility properties
- 306 Downloads
The aim of this study is to evaluate the MR imaging behavior of ferrous (Fe2+) and ferric (Fe3+) iron ions in order to develop a noninvasive technique to quantitatively differentiate between both forms of iron.
MRI was performed at 3 T in a phantom consisting of 21 samples with different concentrations of ferrous and ferric chloride solutions (between 0 and 10 mmol/L). A multi-echo spoiled gradient-echo pulse sequence with eight echoes was used for both T 2* and quantitative susceptibility measurements. The transverse relaxation rate, R 2* = 1/T 2*, was determined by nonlinear exponential fitting based on the mean signals in each sample. The susceptibilities, χ, of the samples were calculated after phase unwrapping and background field removal by fitting the spatial convolution of a unit dipole response to the measured internal field map. Relaxation rate changes, ΔR 2*(c Fe), and susceptibility changes, Δχ(c Fe), their linear slopes, as well as the ratios ΔR 2*(c Fe) / Δχ(c Fe) were determined for all concentrations.
The linear slopes of the relaxation rate were (12.5 ± 0.4) s−1/(mmol/L) for Fe3+ and (0.77 ± 0.09) s−1/(mmol/L) for Fe2+ (significantly different, z test P < 0.0001). The linear slopes of the susceptibility were (0.088 ± 0.003) ppm/(mmol/L) for Fe3+ and (0.079 ± 0.006) ppm/(mmol/L) for Fe2+. The individual ratios ΔR 2*/Δχ were greater than 40 s−1/ppm for all samples with ferric solution and lower than 20 s−1/ppm for all but one of the samples with ferrous solution.
Ferrous and ferric iron ions show significantly different relaxation behaviors in MRI but similar susceptibility patterns. These properties can be used to differentiate ferrous and ferric samples.
KeywordsMagnetic resonance imaging Iron Ferric and ferrous chloride Relaxation Magnetic susceptibility
Compliance with ethical standards
This study was partly funded by the Lüneburg Heritage and Deutsche Forschungsgesellschaft (DFG) Grant BO 1895/4-1 to KB.
Conflict of interest
The authors declare that they have no conflict of interest.
This article does not contain any studies with human participants or animals performed by any of the authors. For this type of study, formal consent is not required.
Statement of informed consent was not applicable since the manuscript does not contain any patient data.
- 1.Singh N, Haldar S, Tripathi AK, Horback K, Wong J, Sharma D, Beserra A, Suda S, Anbalagan C, Dev S et al (2014) Brain iron homeostasis: from molecular mechanisms to clinical significance and therapeutic opportunities. Antioxid Redox Signal 20:1324–1363. doi: 10.1089/ars.2012.4931 CrossRefPubMedPubMedCentralGoogle Scholar
- 3.Schweitzer AD, Liu T, Gupta A, Zheng K, Seedial S, Shtilbans A, Shahbazi M, Lange D, Wang Y, Tsiouris AJ (2015) Quantitative susceptibility mapping of the motor cortex in amyotrophic lateral sclerosis and primary lateral sclerosis. AJR Am J Roentgenol 204:1086–1092. doi: 10.2214/AJR.14.13459 CrossRefPubMedPubMedCentralGoogle Scholar
- 4.Dominguez JF, Ng AC, Poudel G, Stout JC, Churchyard A, Chua P, Egan GF, Georgiou-Karistianis N (2016) Iron accumulation in the basal ganglia in Huntington’s disease: cross-sectional data from the IMAGE-HD study. J Neurol Neurosurg Psychiatry 87:545–549. doi: 10.1136/jnnp-2014-310183 CrossRefPubMedGoogle Scholar
- 7.Popescu BF, George MJ, Bergmann U, Garachtchenko AV, Kelly ME, McCrea RP, Luning K, Devon RM, George GN, Hanson AD et al (2009) Mapping metals in Parkinson’s and normal brain using rapid-scanning x-ray fluorescence. Phys Med Biol 54:651–663. doi: 10.1088/0031-9155/54/3/012 CrossRefPubMedGoogle Scholar
- 10.Hillmer AS, Putcha P, Levin J, Hogen T, Hyman BT, Kretzschmar H, McLean PJ, Giese A (2010) Converse modulation of toxic alpha-synuclein oligomers in living cells by N’-benzylidene-benzohydrazide derivates and ferric iron. Biochem Biophys Res Commun 391:461–466. doi: 10.1016/j.bbrc.2009.11.080 CrossRefPubMedGoogle Scholar
- 15.Zecca L, Gallorini M, Schunemann V, Trautwein AX, Gerlach M, Riederer P, Vezzoni P, Tampellini D (2001) Iron, neuromelanin and ferritin content in the substantia nigra of normal subjects at different ages: consequences for iron storage and neurodegenerative processes. J Neurochem 76:1766–1773CrossRefPubMedGoogle Scholar
- 22.Rumzan R, Wang JJ, Zeng C, Chen X, Li Y, Luo T, Lv F, Wang ZP, Hou H, Huang F (2013) Iron deposition in the precentral grey matter in patients with multiple sclerosis: a quantitative study using susceptibility-weighted imaging. Eur J Radiol 82:e95–e99. doi: 10.1016/j.ejrad.2012.09.006 CrossRefPubMedGoogle Scholar
- 27.Fricke H, Morse S (1927) The chemical action of roentgen rays on dilute ferrosulphate solutions as a measure of dose. Am J Roentgenol Radium Ther 18:430–432Google Scholar
- 35.Fulay PP (2010) Electronic, magnetic, and optical materials. CRC Press, Boca Raton, London, New YorkGoogle Scholar