Periodic Reporting for period 3 - LASER OPTIMAL (Laser Ablation: SElectivity and monitoRing for OPTImal tuMor removAL)
Período documentado: 2021-05-01 hasta 2022-10-31
We established the feasibility of fiber Bragg grating (FBG) arrays as minimally invasive multipoint temperature measurement sensors during in vivo gold nanorod-mediated photothermal therapy in breast cancer models, for achieving high spatial resolution and multiple sensing points in a sub-centimetric long subcutaneous tumor. We analyzed the thermal response induced by different combinations of gold nanorods (GNRs) and NIR laser wavelengths during GNR-assisted photothermal therapy in breast cancer syngrafts in mice. The assessment of quasi-distributed FBGs and Rayleigh scattering-based distributed sensing for accurate and millimeter resolved thermometry in media undergoing laser ablation (LA) was performed. Results showed the excellent performances of laser femtosecond-inscribed highly-dense FBGs for thermometry during LA applications. Thus, the team developed the first software for real-time tissue temperature profiles reconstruction along FBG arrays. Reconstructed temperature data are used to obtain temperature maps of the ablated tissue in real-time during LA procedures. Another software was devised and designed to perform LA power regulation based on real-time temperature monitoring with FBG arrays.
The team has also worked on the implementation of a first-stage computational model based on FEM analysis to simulate the laser ablation treatment for tumor removal, in presence of biocompatible gold nanorods, for the enhancement of the therapy selectivity. The heat transfer in tissue was computed with the Pennes’ bioheat equation, and the simulation of the laser-tissue-nanorods interaction relied on the Mie Theory. Two first in vivo animal studies have been carried out with the Partners of the Consortium to evaluate the thermal effects of different nanoparticles for enhancing laser therapy, and to assess novel and unconventional imaging modalities for thermal damage monitoring, such as hyperspectral imaging. Here, our new methodology quantifies the temperature-related change of tissue chromophores for monitoring thermal damage during LA treatments.