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author:("koschi, Olaf")
1.  A reference dataset for verifying numerical electrophysiological heart models 
Background
The evaluation, verification and comparison of different numerical heart models are difficult without a commonly available database that could be utilized as a reference. Our aim was to compile an exemplary dataset.
Methods
The following methods were employed: Magnetic Resonance Imaging (MRI) of heart and torso, Body Surface Potential Maps (BSPM) and MagnetoCardioGraphy (MCG) maps. The latter were recorded simultaneously from the same individuals a few hours after the MRI sessions.
Results
A training dataset is made publicly available; datasets for blind testing will remain undisclosed.
Conclusions
While the MRI data may provide a common input that can be applied to different numerical heart models, the verification and comparison of different models can be performed by comparing the measured biosignals with forward calculated signals from the models.
doi:10.1186/1475-925X-10-11
PMCID: PMC3037925  PMID: 21272330
2.  Ultra-Wideband Sensors for Improved Magnetic Resonance Imaging, Cardiovascular Monitoring and Tumour Diagnostics 
Sensors (Basel, Switzerland)  2010;10(12):10778-10802.
The specific advantages of ultra-wideband electromagnetic remote sensing (UWB radar) make it a particularly attractive technique for biomedical applications. We partially review our activities in utilizing this novel approach for the benefit of high and ultra-high field magnetic resonance imaging (MRI) and other applications, e.g., for intensive care medicine and biomedical research. We could show that our approach is beneficial for applications like motion tracking for high resolution brain imaging due to the non-contact acquisition of involuntary head motions with high spatial resolution, navigation for cardiac MRI due to our interpretation of the detected physiological mechanical contraction of the heart muscle and for MR safety, since we have investigated the influence of high static magnetic fields on myocardial mechanics. From our findings we could conclude, that UWB radar can serve as a navigator technique for high and ultra-high field magnetic resonance imaging and can be beneficial preserving the high resolution capability of this imaging modality. Furthermore it can potentially be used to support standard ECG analysis by complementary information where sole ECG analysis fails. Further analytical investigations have proven the feasibility of this method for intracranial displacements detection and the rendition of a tumour’s contrast agent based perfusion dynamic. Beside these analytical approaches we have carried out FDTD simulations of a complex arrangement mimicking the illumination of a human torso model incorporating the geometry of the antennas applied.
doi:10.3390/s101210778
PMCID: PMC3231085  PMID: 22163498
Ultra-wideband (UWB) radar; electrocardiography (ECG); myocardial surface; high and ultra-high field magnetic resonance imaging (MRI); fMRI, multimodal sensing; Finite-difference time-domain method (FDTD)
3.  Pseudo current density maps of electrophysiological heart, nerve or brain function and their physical basis 
Background
In recent years the visualization of biomagnetic measurement data by so-called pseudo current density maps or Hosaka-Cohen (HC) transformations became popular.
Methods
The physical basis of these intuitive maps is clarified by means of analytically solvable problems.
Results
Examples in magnetocardiography, magnetoencephalography and magnetoneurography demonstrate the usefulness of this method.
Conclusion
Hardware realizations of the HC-transformation and some similar transformations are discussed which could advantageously support cross-platform comparability of biomagnetic measurements.
doi:10.1186/1477-044X-4-5
PMCID: PMC1660567  PMID: 17040559

Results 1-3 (3)