Ultrasound (US) is a non-invasive technique for anatomical and functional in vivo micro-imaging. The MOIN CC is equipped with a Vevo 770™ ultrasound system from Visual Sonics that offers a resolution of 30 µm axial and 75 µm radial. Small animal imaging is facilitated by two real-time micro visualization scan heads with a frequency range of 22-83 MHz and 12-38 MHz respectively, optimized for visceral or cardiac imaging in mouse and rat.
MOIN CC research uses this ultrasound system especially in oncological cooperations, where it is used for tumor monitoring and volumetrics during longitudinal studies and for precise, ultrasound-aided surgical procedures on mice.
Photoacoustics is an ultrasound-based technique for parallel non-invasive anatomical, functional, physiological and molecular imaging. In photoacoustics, energy is transferred into tissues by a non-ionizing laser pulse. Some of the energy is converted into heat, causing a local thermal expansion that produces an ultrasonic emission. Since the magnitude of the emitted signal correlates with the optical absorption of the tissue, detection with an ultrasound scan head can be used to create two- or three-dimensional images. The system is well-suited for vascular imaging, with information about the oxygenation from the photoacoustic absorption and the blood flow acquired in the ultrasound Doppler-mode. Additionally, molecular information can be gathered by fluorescent staining with for example antibody-coupled fluorophores or targeted liposomal nanoparticles and co-registered with anatomical images from the ultrasound examination. The great advantage of photoacoustics is the possibility to perform longitudinal studies with molecular and cellular deep tissue imaging in a non-invasive setting.
The MOIN CC owns a Vevo® LAZR from Visual Sonics based on the Vevo® 2100 platform for enhanced and overlaid optical and ultrasound imaging. The system offers a real-time resolution down to 45 µm spatial and 740 frames per second in 2D temporal. Current research projects by the MOIN CC or cooperation partners include inflammation and tumor imaging as well as oxygenation studies. Also, the MOIN CC is working on functional liposomal nanoparticles that facilitate the targeted molecular imaging of cells or tissues in photoacoustics.