Developing magnetorelaxometry imaging for human applications

Objective. Magnetic nanoparticles (MNPs) are a promising tool in biomedical applications such as cancer therapy and diagnosis, where localization and quantification of MNP distributions are often mandatory. This can be obtained by magnetorelaxometry imaging (MRXI). Approach. In this work, the capability of MRXI for quantitative imaging of MNP inside larger volumes such as a human head is investigated. We developed a human head phantom simulating a glioblastoma multiforme (GBM) tumor containing MNP for magnetic hyperthermia treatment. The sensitivity of our MRXI setup for detection of MNP concentrations in the range of 3-19 mg cm(-3) was studied. Main result. The results show the high capability of MRXI to detect MNPs in a human head sized volume. Superficial sources with a concentration larger than 12 mg cm(-3) could be reconstructed with a resulotion of about 1 cm(-3). Significance. The reconstruction of the MNP distribution, mimicking a GBM tumor of 7 cm(3) volume with clinically relevant iron concentration, demonstrates the in vivo feasibility of MRXI in humans.

Automated summary

Magnetic nanoparticles (MNPs) are important in biomedical applications, and magnetorelaxometry imaging (MRXI) can be used for the localization and quantification of MNP distributions. This study investigates the capability of MRXI for quantitative imaging of MNPs in larger volumes such as the human head, and demonstrates its high sensitivity for detecting MNPs.