Institute of Electrical and Biomedical Engineering, UMIT - Private University for Health Sciences, Medical Informatics and Technology, 6060 Hall in Tirol, Austria.
Department Biosignals, PTB - Physikalisch-Technische Bundesanstalt, 10587 Berlin, Germany.
Sensors (Basel). 2020 Jan 29;20(3):753. doi: 10.3390/s20030753.
For biomagnetical applications exploiting physical properties of magnetic nanoparticles (MNP), e.g., magnetic hyperthermia, knowledge about the quantitative spatial MNP distribution is crucial, which can be extracted by magnetorelaxometry (MRX) imaging. In this paper, we present quantification, quantitative 1D reconstruction, and quantitative 2D imaging of MNP by exploiting optically pumped magnetometers for MRX. While highlighting the potential of commercially available optically pumped magnetometers (OPM) for MRXI, we discuss current limitations of the used OPM. We show, that with our OPM setup, MNP can be precisely quantified with iron amounts down to ≈ 6 g , which can be improved easily. With a 1D-reconstruction setup, point-like and complex MNP phantoms can be reconstructed quantitatively with high precision and accuracy. We show that with our developed 2D MRX imaging setup, which measures 12 c m by 8 c m , point-like MNP distributions with clinically relevant iron concentrations can be reconstructed precisely and accurately. Our 2D setup has the potential to be easily extended to a tomography styled (and thus slice-selective) 3D scanner, by adding a mechanical axis to the phantom.
对于利用磁性纳米粒子 (MNP) 物理特性的生物磁学应用，例如磁热疗，定量的空间 MNP 分布知识是至关重要的，这可以通过磁弛豫测量 (MRX) 成像来提取。在本文中，我们通过利用光泵磁力计进行 MRX 来实现 MNP 的定量、一维重建和二维成像。在强调商用光泵磁力计 (OPM) 在 MRXI 中的潜力的同时，我们还讨论了所使用的 OPM 的当前限制。我们表明，通过我们的 OPM 装置，可以精确地定量测量低至 ≈ 6 克的铁量，这很容易得到改进。通过一维重建装置，可以高精度、高准确度地重建点状和复杂的 MNP 体模。我们展示了，通过我们开发的二维 MRX 成像装置，它的测量范围为 12 厘米乘 8 厘米，可以精确、准确地重建具有临床相关铁浓度的点状 MNP 分布。我们的二维装置具有通过向体模添加机械轴很容易扩展到层析样式 (即切片选择) 的 3D 扫描仪的潜力。
