Christian Bruns

Otto-von-Guericke-Universität Magdeburg | OvGU · Department for Biometrics and Medical Informatics

The radio-frequency (RF) transmit power deposition in tissue during magnetic resonance imaging (MRI) at ultra-high fields, i.e. B 0 ≥ 7 T, is a major challenge for pulse sequences requesting large flip angles. The absorbed RF energy can pose safety risk to patients as it is rising temperature in the tissue. The temperature can be accessed using MRI...

In biological tissues, ¹⁹ F magnetic resonance (MR) enables the non-invasive, background-free detection of ¹⁹ F-containing biomarkers. However, the signal-to-noise ratio (SNR) is usually low because biomarkers are typically present at low concentrations. Measurements at low magnetic fields further reduce the SNR. In a proof-of-principal study we ap...

At ultra-high field MRI (Bo>7T) it is crucial to predict and control the patient safety. Commonly patient safety is controlled by the power deposited in the tissue (specific absorption rate - SAR). However, temperature distributions do not always correlate directly with SAR distributions, which makes temperature control also a crucial parameter to...

The interest in fluorinated substances has increased significantly in recent decades due to their diverse properties and possible uses. An important analytical method in this context is NMR spectroscopy, which provides information on the structure as well as on intermolecular interactions or generally on changes in the environment of the nucleus un...

In biological tissues, ¹⁹ F magnetic resonance (MR) enables the non-invasive, background-free detection of ¹⁹ F-containing biomarkers. However, the signal-to-noise ratio (SNR) is usually low because biomarkers are typically present at low concentrations. Measurements at low magnetic fields further reduce the SNR. We therefore applied LED-based phot...

Although ¹⁹F has high potential to serve as a background-free molecular marker in bioimaging, the molar amount of marker substance is often too small to enable ¹⁹F MR imaging or ¹⁹F NMR spectroscopy with a sufficiently high signal-to-noise ratio (SNR). Hyperpolarization methods such as parahydrogen-based hyperpolarization or dynamic nuclear polariz...

Although 19F has high potential to serve as a background-free molecular marker in bioimaging, the molar amount of marker substance is often too small to enable 19F MR imaging or 19F NMR spectroscopy with a sufficiently high signal-to-noise ratio (SNR). Hyperpolarization methods such as parahydrogen-based hyperpolarization or dynamic nuclear polariz...

Background The consent management is an essential component for supporting the implementation of consents and withdrawals and thus, the realisation of patient’s rights. In MIRACUM, one of the four consortia of the Medical Informatics Initiative (MII), ten university hospitals intend to integrate the generic Informed Consent Service® (gICS) in their...

Background: The COVID-19 pandemic hit the German education system unexpectedly and forced its universities to shift to Emergency Remote Teaching (ERT). The Data Integration Center (DIC) of the University Hospital Magdeburg and the Institute of Biometry and Medical Informatics (IBMI) has developed a concept based on existing structures that can be q...

Substrates containing ¹⁹F can serve as background‐free reporter molecules for NMR and MRI. But in vivo applications are still limited due to the lower signal‐to‐noise ratio (SNR) when compared with ¹H NMR. Although hyperpolarization can increase the SNR, to date, only photo‐chemically induced dynamic nuclear polarization (photo‐CIDNP) allows for hy...

Magnetic resonance imaging (MRI) at ultra-high fields (UHF), such as 7 T, provides an enhanced signal-to-noise ratio and has led to unprecedented high-resolution anatomic images and brain activation maps. Although a variety of radio frequency (RF) coil architectures have been developed for imaging at UHF conditions, they usually are specialized for...

B1 flip angle maps (DICOM format) of the water-NaCl-isopropanol phantom (transversal and coronal slices) and the crab-eating macaque (with sagittal slice). (Fig 4_Phantom_B1_cor.dcm; Fig 4_Phantom_B1_trans.dcm; Fig 5_monkey_b1_map.dcm). (ZIP)

A remote transmission and detection for magnetic resonance imaging (MRI) at 7 T was validated by using a patch antenna that excites the traveling-wave (TW) modes guided by the radio frequency (RF) shield of the MRI system. In this paper, RF simulations were performed at 298 MHz for an eight-element stepped impedance resonators (SIRs) head volume co...

ABSTRACT The dynamics of scroll waves in a narrow cylinder jacket–shaped reactor is investigated experimentally by optical tomography. The fate of the scroll waves of excitation in the Belousov-Zhabotinsky reaction depends on the thickness of the cylinder jacket. While at sufficiently wide cylinder jackets vertically oriented scroll waves remain st...

A remote transmission and detection for magnetic resonance imaging (MRI) at 7 T was validated by using a patch antenna that excites the traveling-wave (TW) modes guided by the radio frequency (RF) shield of the MRI system. In this paper, RF simulations were performed at 298 MHz for an eight-element stepped impedance resonators (SIRs) head volume co...

In ultra-high-field brain MR imaging, the coverage for imaging with the optimized protocol is constrained not only by scan time, but also by the coil structure. Since presently available surface loop RF coils have limited field of view, it is very difficult to achieve the coverage from the top of the head to the end of the cervical vertebrae. Prior...

A multi-element microstrip transceiver array is a promising approach for magnetic resonance imaging (MRI) at 7T (298 MHz). Travelling wave (TW) MRI is another method where the RF magnetic field B1+ is carried by propagating circularly polarized modes excited from an antenna located at one end of the MRI system bore. In this paper, full-wave electro...

Objectives : Ultra-high field MRI with an acceptable combination of B1+-field homogeinity and signal-to-noise-ratio (SNR) is challenging. To increase the SNR of a head coil, the use of monopole arrays was recently proposed for UHF MRI applications [1]. However such arrays suffer from high couplings which prevent parallel imaging. As mitigation, we...