Prof. Dr. rer. nat. Dr. med. Wolfhard Semmler

3D reconstruction of the oxygen-17 MR data set of the human brain. Due to the low natural abundance of the oxygen isotope 17O images of the brain can only be acquired in reasonable measurement times at high field strengths.

The Department of Medical Physics in Radiology plays a pivotal role in all imaging-based procedures, developing new and optimizing existing imaging methods. In order to optimize and individualize cancer patient’s treatment and local tumor control, quantitative biomedical information about metabolic, physiologic and functional parameters of tumors is essential. We are establishing new methods and technologies of cancer diagnostics and are improving existing ones, e.g. expanding the diagnostic value of 7T MRT by Na-23 and O-17 imaging, extending noninvasive diagnostic methods. Through the development of MRT diffusion measurement techniques we gain additional information about cellular membranes and incoherent capillary flow in tumor tissue. Furthermore, we develop noninvasive diagnostic methods for the assessment of blood flow, mean transit times and perfusion in body organs and in particular tumors as well as imaging techniques for detection and in vivo characterization of experimental metastases on the micro-morphological, functional and molecular level. We develop new designs and devices (e.g. nanosurfaces), chemical syntheses, and the re-formulation of already in use active compounds for study and intervention of biological processes including those related to genetic diseases. These products permit all conceivable biophysical techniques (high field MRT, CT, PET, NIR imaging) to monitor the molecular processes in a relevant pharmacological context.

The major objectives for the future will be research projects with the 7 T-system; molecular imaging with a focus onmetastatic processes; futher development of interventional procedures, and of photon-based small-animal emissiontomographic systems.
To fulfill these objectives, the Department’s five-year plan is to:

• qualify the Department as a center of excellence in oncologic imaging methodology and continue and strengthen the support for the clinical departments.
• develop and introduce new MR imaging methods suitable for oncological diagnostics and therapy, in particular for 7T field strength, but also for the 3T and 1.5 T-systems.
• implementation of a new working group concerning high-end CT development and reconstruction algorithm.
• develop new experimental multimodal imaging modalities and pave the way for molecular and functional imaging, in particular for imaging metastases.
• participate in the development of a combined MRI-Linac–system to enhance online position control and online motion correction to further improve radiotherapy.