The blood-brain barrier serves as a natural protection mechanism against harmful substances. When it comes to the effective treatment of brain related diseases however, this barrier poses a significant obstacle. Multiple approaches to overcome the blood-brain barrier have been evaluated in recent years. Ultrasound as a non-invasive treatment method allows the transient opening of the blood-brain barrier, as shown in multiple animal trials and first human trials. To minimize animal experiments, efforts to bridge the gap between in vitro cell models and in vivo experiments are necessary. In our study, we simulated and built a well plate sonication device allowing the parallel ultrasound-treatment

of 12 in vitro blood-brain barrier cell models.

With the evolving potential of therapeutic ultrasound as a treatment method for various medical conditions, the need for the reliable monitoring of therapy accompanying effects such as cavitation is growing simultaneously. While the use of separate transducers is a simple approach for the implementation of the cavitation monitoring of ultrasound therapy, the structural integration of receiving elements in the therapy probe offers several advantages (compactness, fixed co-registration). In our study, we present two in-house built therapy transducers with different geometries operating at different frequencies (1 MHz preclinical /480 kHz clinical), which are both combined with 32 receiving elements for the simultaneous 3D cavitation monitoring (passive acoustic mapping, PAM) using different design approaches.

Ultrasound neurostimulation is a promising new technique for treatment of conditions such as Parkinsons or Essential Tremor, which can be a non-invasive alternative to established approaches such as deep brain stimulation. For achieving isotropic resolution, up to now only very complex systems involving conformal transducer arrays (“helmet-like”) are used. Matrix-array transducers can typically provide high x- and y- resolution but have a significantly larger focus size in z-direction (along the acoustic axis of the array). Using different matrix arrays in a cross-beam setup allows overcoming theses challenges. In such a setup, the x/y- focus size is defined by the focusing capabilities of the matrix and the z-focus results from the overlap of both sound fields.