Microscopy and Biomedical Imaging
Modern imaging techniques are required to enable precise diagnostics and to be as harmless as possible for the patient at the same time. At the MSB, numerous researchers work towards this goal: they refine established diagnostic procedures, exploit further physical processes for novel medical imaging and microscopy methods and concepts, and optimize current methods for different medical purposes. Several MSB scientists also study methods that combine medical imaging with radiation therapy.
Biological and Optical Imaging
Optoacoustic imaging, or photoacoustic imaging, is insensitive to photon scattering within biological tissue and, unlike conventional optical imaging methods, and makes high-resolution optical visualization deep within tissue possible. Recent advances in laser technology, detection strategies and inversion techniques have led to significant improvements in the capabilities of optoacoustic systems. A key empowering feature - pioneered at TUM - is the development of video-rate multispectral imaging in two and three dimensions, which offers fast, spectral differentiation of distinct photo-absorbing modalities.
Phase-Contrast X-Ray Imaging
The basic physics principles of x-ray image formation in radiology have remained essentially unchanged since Röntgen first discovered x-rays over a hundred years ago. The conventional approach relies on x-ray attenuation as the sole source of contrast and ignores another, complementary source of contrast. Phase-contrast imaging techniques, on the other hand, offer ways to augment or complement standard attenuation contrast by incorporating phase information. In the recent past several developments have been made that now allow translating x-ray phase-contrast to future clinical applications in radiography and computed tomography.
07.05.2020 | New x-ray method for Corona diagnosis ready for patient testing – Low-dose radiographs could reveal typical lung changes (Background Information:
<link en/research/microscopy-and-biomedical-imaging/grating-based-x-ray-dark-field-imaging/ - link--internal>Description of the principle behind dark-field imaging</link> )
14.01.2020 | Precise monitoring of the lung – X-rays and fluorescence imaging of the lungs of a mouse enable tracking of drug delivery
TUM press releases:
27.02.2017 | Mini particle accelerator saves on contrast agents
29.10.2015 | New state-of-the-art compact X-ray source
30.04.2015 | Compact synchrotron makes tumors visible
Nuclear Magnetic Resonance Imaging
Nuclear Magnetic Resonance (NMR) is a spectroscopic method, which is commonly used in science to elucidate the structure and dynamics of molecules. It uses strong magnetic fields (up to 23 Tesla) with highest homogeneity, temporal stability, and with radio frequency fields (up to 1 GHz). The additional use of magnetic field gradients (up to 1 Tesla/m) allows for the acquisition of MR images.
In general, Magnetic Resonance Imaging (MRI) uses the 1H MR signal from water and lipid molecules to create 2D or 3D images of biological objects (organs, animals, plants, human subjects). MRI is a non-invasive method and shows no biological side effects.
Therefore it is ideally suited to study and visualize the anatomy, function and metabolism of internal organs.
Tissue based morphomolecular “imaging” and deep multiparameter characterization has become one of the cornerstone of individualized patient care. The integration of histology with molecular information such as sequencing results or imaging mass spectrometry data allows for a deeper biological understanding of diseases and thus for tailored therapeutic approaches. This is specifically important in the field of oncology where such integrated multiparameter “imaging” datasets already dictate therapeutic decisions and allow for the application of novel drugs which prolong patient survival substantially. To exploit the tremendous new set of morphomolecular disease information at hand new methods of bioinformatics and computer learning have to be applied and will further deepen our understanding of the true nature of disease.
Biomedical Imaging Physics
We develop novel X-ray imaging methods using highly brilliant synchrotron radiation and conventional laboratory X-ray sources. We mainly focus on quantitative multi-modal approaches combining spectral and phase-contrast imaging. Currently, we are aiming at applying these methods for improved breast cancer detection and for quantitative 3D virtual histology of human tissue.
TEDx Talk (Youtube-Video): Novel X-Ray technology that can revolutionize preventive medicine
Magnetic Resonance Imaging Biomarkers
Magnetic resonance imaging biomarkers enable a comprehensive characterization of tissue providing functional, physiological, metabolic, cellular and molecular information beyond anatomical structures. In recent years, hyperpolarization techniques allowed to increase the inherent low sensitivity of magnetic resonance by more than four orders of magnitude, opening new applications ranging from the tracking of chemical reactions in real-time to the direct monitoring of metabolic processes in vivo. Another functional MRI technique that has already shown promise in characterizing tissue in clinical studies is diffusion-weighted MRI (DW-MRI). It enables the quantitative assessment of the apparent diffusion coefficient (ADC) that depends on microstructural tissue properties, including cellularity and intercellular matrix composition. At TUM, sensitive hyperpolarized molecules and advanced diffusion MRI techniques are being developed aiming to provide novel imaging biomarkers to characterize tissue function.
Experimental Magnetic Resonance Imaging
Our research focuses on the development of novel Magnetic Resonance Imaging (MRI) and Magnetic Resonance Spectroscopy (MRS) acquisition, reconstruction and signal modeling methods with an emphasis on the extraction of quantitative imaging biomarkers. We are developing novel methods for proton density fat fraction mapping, lipid diffusion mapping, quantitative susceptibility mapping, T2 and T2* mapping, diffusion tensor imaging and body diffusion-weighted imaging. The developed methods are being translated into clinical studies for improving the diagnosis, the therapy monitoring, and the understanding of disease pathophysiology in the diseases of the musculoskeletal system (e.g. osteoporosis, neuropathies, neuromuscular diseases), in metabolic dysfunction (e.g. obesity, diabetes, cachexia) and in body oncology.
Theranostics, the combination of imaging and targeted radionuclide therapy, aims to treat cancer by radioisotopes that specifically accumulate in the tumor tissue due to molecular targeting. Theranostics expands the use of radiotherapy - one of the most effect therapies for virtually all cancers - to the treatment of patients with metastatic disease. Quantitative nuclear imaging is used to select patients for targeted radionuclide therapy, calculate radiation doses and monitor tumor response.