Dynamic recording of lateral biomagnetic field distributions with integrated optical magnetometers (magnetic field camera)

使用集成光学磁力计（磁场相机）动态记录横向生物磁场分布

• 批准号: 278356781
• 负责人: Professor Dr.-Ing. Jens Haueisen
• 金额: --
• 依托单位: Leibniz-Institut für Photonische Technologien (IPHT)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/278356781?language=en
• 关键词: Dynamic; recording; lateral; biomagnetic; field

The measurement of magnetic fields of centimeter-sized objects with high magnetic-field, lateral and temporal resolution is of great interest for physical and biomedical research. Using current measurement technologies based on SQUID arrays, the resolution is limited by technological factors such as the sensor size and the sensor-target-distance due to the cryogenic cooling. Optically pumped magnetometers (OPM) allow for first measurements of magnetic fields with a millimeter resolution. However, these measurements are currently performed sequentially by scanning the object of interest. This prevents a synchronous measurement of the magnetic field with high spatial and temporal resolution. In this project, we want to develop new methods and technologies that allow for the measurement of magnetic fields of centimeter-sized objects with lateral resolutions in the range of millimeters, a magnetic field resolution in the range of pico Tesla, and a bandwidth of 100 Hz. The measurements should be feasible at external magnetic fields of about 50 micro Tesla, the typical strength of the earth magnetic field in our latitudes, without the need of costly magnetic shielding. To realize this objective, novel optically pumped magnetometers need to be developed. This requires both the development of a new mode of operation for optically pumped magnetometers, which, for the first time, allows for the parallel dynamic recording of two-dimensional magnetic fields, as well as the adaptation of integrated optical absorption cells to the requirements arising from the new mode of operation and the targeted lateral resolution. In addition, new methods for solving the magnetic inverse problem are to be developed, which allow on the one hand to adjust the parameters of the measurement system and on the other hand to reconstruct the sources of the magnetic field inside the examined object. The recording system and the reconstruction algorithms are to be validated against measurements with special technical phantoms. The realization of this innovative measurement system opens up a variety of applications. An important example is the measurement of biomagnetic fields in animal experimental research. The measurement of magnetocardiograms of small animals (e.g. mice) with high spatial and temporal resolution could e.g. be used for monitoring the effect of drugs with high throughput rates. The measurement of magnetoencephalograms of small animals is of high interest for neuroscientific research on epileptic activity, for which intracortical currents need to be reconstructed with high spatial resolution due to the small size of cortical areas in small animals.

厘米级物体的磁场测量具有很高的磁场、横向和时间分辨率，是物理和生物医学研究的重要内容。使用基于SQUID阵列的当前测量技术，分辨率受到诸如传感器尺寸和由于低温冷却而导致的传感器-目标距离的技术因素的限制。光泵磁力计（OPM）允许以毫米分辨率首次测量磁场。然而，这些测量当前通过扫描感兴趣对象来顺序地执行。这阻止了以高空间和时间分辨率同步测量磁场。在这个项目中，我们希望开发新的方法和技术，允许测量厘米大小物体的磁场，横向分辨率在毫米范围内，磁场分辨率在皮科范围内，带宽为100 Hz。在大约50微特斯拉的外部磁场下，测量应该是可行的，这是我们纬度地区地球磁场的典型强度，而不需要昂贵的磁屏蔽。为了实现这一目标，需要开发新型的光泵磁强计。这就需要开发一种新的光泵磁力计操作模式，这是第一次允许并行动态记录二维磁场，以及集成光吸收单元适应新操作模式和目标横向分辨率所产生的要求。此外，将开发用于解决磁逆问题的新方法，其一方面允许调整测量系统的参数，另一方面允许重建被检查对象内部的磁场源。记录系统和重建算法将根据特殊技术模型的测量结果进行验证。这种创新测量系统的实现开辟了各种应用。一个重要的例子是动物实验研究中的生物磁场测量。具有高空间和时间分辨率的小动物（例如小鼠）的心磁图的测量可以例如用于以高通量速率监测药物的效果。小动物脑磁图的测量对于癫痫活动的神经科学研究具有很高的兴趣，由于小动物的皮质区域尺寸小，因此需要以高空间分辨率重建皮质内电流。

项目成果

Head phantoms for electroencephalography and transcranial electric stimulation: a skull material study

• DOI: 10.1515/bmt-2017-0069
• 发表时间: 2018-12-01
• 期刊: BIOMEDICAL ENGINEERING-BIOMEDIZINISCHE TECHNIK
• 影响因子: 1.7
• 作者: Hunold, Alexander;Strohmeier, Daniel;Haueisen, Jens
• 通讯作者: Haueisen, Jens

Sensitivity studies and optimization of arrangements of optically pumped magnetometers in simulated magnetoencephalography

• DOI: 10.1108/compel-09-2018-0372
• 发表时间: 2019-05-07
• 期刊: COMPEL-THE INTERNATIONAL JOURNAL FOR COMPUTATION AND MATHEMATICS IN ELECTRICAL AND ELECTRONIC ENGINEERING
• 影响因子: 0.7
• 作者: Eichardt, Roland;Strohmeier, Daniel;Graichen, Uwe
• 通讯作者: Graichen, Uwe