The aim of this project is to evaluate systematically how ultrasound waveguiding can promote light delivery deep into scattering tissue and by that enable optical and photoacoustic imaging of biomedical tissue with increased penetration depth. For photoacoustic imaging we aim at an increase of penetration depth of an existing handheld scanner exceeding 2-3 cm within the near infrared optical window (808 nm).

Based on our preliminary studies, we develop numerical models for ultrasound and light propagation in scattering media as well as for the ultrasound mediated light waveguiding. With those models, we derive optimum settings for experimental configurations. Consequently, these settings will be implemented and systematically experimentally analyzed with scattering phantoms and solutions.

Finally, we combine the optimized concept with photoacoustic imaging and develop concepts for photoacoustic imaging at larger penetration depth due to ultrasound mediated light guiding. In summary, we have two main goals:

1. A comprehensive understanding of the physical effects underlying the ultrasound induced light waveguiding in scattering media
2. Demonstration of high penetration depth via ultrasound induced waveguiding in photoacoustic imaging

In case of success, our concept will promote not only optical approaches in biomedical imaging such as photoacoustic imaging and diffuse optical tomography but also optical treatment like laser surgery.