Only strongly enhanced residual FDG uptake in early response PET (Deauville 5 or qPET ≥ 2) is prognostic in pediatric Hodgkin lymphoma: Results of the GPOH-HD2002 trial.

Purpose: In 2014, we published the qPET method to quantify fluorodeoxyglucose positron emission tomography (FDG-PET) responses. Analysis of the distribution of the quantified signals suggested that a clearly abnormal FDG-PET response corresponds to a visual Deauville score (vDS) of 5 and high qPET values ≥ 2. Evaluation in long-term outcome data is still pending.

MR-tomography on patients with heart pacemakers-a numerical study.

Patients having a heart pacemaker are not allowed to go to MR tomography (MRT). One of the most dangerous effects is the heating of the tissue around the electrode caused by the coupling to the RF field of the MR system. Experiments have been carried out using tanks filled with saline water and large heating has sometimes been observed.

Improvement of patient return electrodes in electrosurgery by experimental investigations and numerical field calculations.

Numerical field calculations and experimental investigations were performed to examine the heating of the surface of human skin during the application of a new electrode design for the patient return electrode. The new electrode is characterised by an equipotential ring around the central electrode pads. A multi-layer thigh model was used, to which the patient return electrode and the active electrode were connected.

Development and characterisation of a ceramic HF-resonator for the MR-tomography.

Future trends in magnetic resonance imaging (MRI) lead to higher magnetic field strengths of the static magnetic fields and as an implication of that to much higher frequencies. Nowadays a common model of a send-receive coil is the birdcage resonator. However it is very difficult to find an optimal L/C-relation for the capacities and inductivities at frequencies above 300 MHz.

Simulation of a birdcage and a ceramic cavity HF-resonator for high magnetic fields in magnetic resonance imaging.

The aim of this work was the 3D-simulation of a dielectric resonator for high-field-MRI. A 12-rod-bird-cage-resonator was simulated in a first step, in order to verify the capability of the commercial simulation software MAFIA to simulate homogeneous, transversal B-fields in resonators. The second step was the simulation of frequency-independent dielectric ceramic resonators for static magnetic field strengths of 7 T and 12 T (294 MHz and 504 MHz respectively).