Imaging@CSB

Brain imaging in small animals is used by CSB scientists to study stroke pathophysiology and obtain pathobiological "fingerprints" for translational studies using the same or equivalent imaging technologies in humans. For non-invasive high-resolution imaging of the morphology and functional parameters in the brain (such as blood flow, diffusion, etc.), two preclinical 7 Tesla MRI scanners are available.

Neuroimaging is the main diagnostic tool in stroke, and pivotal for translation, as the same modalities (e.g., MRI, SPECT, PET) can be used in preclinical stroke models and patients. To this end, the CSB has implemented an array of interlinked structures, spanning from the Berlin Experimental Radionucleoid Imaging Center (BERIC) to the preclinical MRI Shared Facility "7T experimental MRIs" and the human 3T MRI scanner attached to the stroke unit at Campus Benjamin Franklin. Together, CSB researchers and clinicians have established novel imaging strategies and investigated mechanisms of brain damage and ways to intercept them, for example:

• Imaging of blood brain barrier (BBB) disruption and the role of inflammation in this process after experimental stroke using iron nanoparticles as well as in human patients using a gadolinium-based contrast agent
• Mapping of brain tissue oxygenation using perfluorocarbon emulsions and fluorine-19 MRI
• Detecting changes in brain connectivity using diffusion- and functional MRI
• Correlating functional recovery with lesion location (lesion symptom mapping)
• Finding biomarkers of ischemic cell death with optical, nuclear or MR imaging and MR spectroscop

A particular focus of the imaging activities in the CSB has been on validating and improving the so-called "mismatch concept", which relies on perfusion-weighted (PW) and diffusion-weighted (DW) MRI to stratify patients to brain protective therapies or to prognosticate final damage (i.e. infarction). In addition our team is pioneering strategies to enable perfusion imaging without the usage of exogenous contrast agents as well as provide a clinically feasible combined measurement of intracerebral perfusion and intracerebral microvasculature.

Our imaging team regularly takes part in multiple trials, observational as well as interventional, dealing with topics as diverse as changing guidelines for the acute treatment of ischemic stroke of unknown onset, understanding mechanisms of acute myocardial damage following stroke and improving secondary prevention post-stroke programs.