Abstract
In modern medicine, wound healing remains a very complex process where the main goal is to achieve a fast regeneration matched to an aesthetically satisfactory appearance. In particular, reducing the wound healing time and minimizing tissue scarring are important requirements. In view of minimally-invasive clinical interventions, nanoparticle-assisted laser tissue soldering is emerging as an appealing concept in surgical medicine due to its ability to facilitate wound healing while avoiding sutures. However, such a therapy has not been employed in clinical settings yet. The underlying reason is the fact that rapid elevation in temperature can cause significant photothermal tissue damage. Therefore, cutting-edge diagnostic tools are indispensable in order to monitor the temperature in tissue and achieve satisfactory healing results. To this end, we propose a non-invasive, non-contact, and non-ionizing modality for monitoring nanoparticle-assisted laser-tissue interaction and visualizing the localized photothermal damage, by taking advantage of the unique sensitivity of terahertz radiation to the hydration level of biological tissue. We demonstrate that terahertz imaging can be employed as a versatile tool to monitor the temperature variations and reveal the thermally affected evolution in tissue. In particular, terahertz imaging is able to provide quantitative information along the depth direction, in turn allowing us to characterize the photothermal damage induced by nanoparticle-assisted laser tissue soldering in three dimensions. Our approach can be easily extended and applied across a broad range of clinical applications associated with laser-tissue interactions, such as laser ablation and photothermal therapies.
