Final Report Summary - DYNAMIT (Deep Tissue Optoacoustic Imaging for Tracking of Dynamic Molecular and Functional Events) The ERC StG had commenced with the overall goal to develop a new generation of high- performance optoacoustic technology capable of real time (video rate) imaging several millimeters to centimeters into living tissues, with both high spatial resolution and sensitivity. In the course of the project, we have established two technological platforms for pushing the envelope of optoacoustic imaging performance.The first microscopic platform was devised to enable real-time observations with microscopic spatial resolution down to 20μm in deep living tissues. Using this newly established optoacoustic microscopy technique, termed hybrid focus optoacoustic microscopy (HFOAM), we have demonstrated functional brain imaging in living mice at a single capillary level. We have also devised approaches for non-invasive optoacoustic neuro-imaging (through an intact skull) by developing new algorithms to overcome limitations imposed by acoustic mismatches of the murine skull.The second technological platform has been established to enable real-time acquisition and visualization of volumetric optoacoustic data. This was achieved by implementing new types of spherical matrix arrays, parallel acquisition hardware, GPU-based data processing, and fast laser wavelength tuning systems. The developed technology has resulted in a creation of a truly novel imaging paradigm, the so-called five-dimensional (5D) optoacoustic tomography, which can render spectrally-enriched information from entire scattering tissue volumes with spatial resolution of 70-200μm, field-of-view of several cubic centimeters and a frame rate of up to 50 volumes per second. This has offered unparallel imaging capacities among the current bio-imaging modalities and we were able to demonstrate fully non-invasive monitoring of brain hemodynamics as well as fast tracking of kinetics and biodistribution in murine models of cardiovascular disease using the new technology. Our preliminary results also proved, for the first time, the fundamental ability to optoacoustically track neural calcium dynamics, thus overcoming the longstanding penetration barrier of optical neuroimaging in scattering brains. Most importantly, the actual handheld system performance went well beyond the initial expectations, which allowed performing initial validation of volumetric optoacoustic angiography in healthy volunteers, thus going beyond the initially defined project’s goals.
