Laser-induced interstitial thermotherapy (LITT) has been recently applied to pancreas in animal models for ablation purpose. Assessment of thermal effects due to the laser-pancreatic tissue interaction is a critical factor in validating the procedure feasibility and safety. A mathematical model based on bioheat equation and its experimental assessment was developed. The LITT procedure was performed on 40 ex vivo porcine pancreases, with an Nd:YAG (1064nm) energy of 1000J and power from 1.5 up to 10W conveyed by a quartz optical fiber with 300μm diameter. Six fiber Bragg grating sensors have been utilized to measure temperature distribution as a function of time at fixed distances from the applicator tip within pancreas undergoing LITT. Simulations and experiments show temperature variations ΔT steeply decreasing with distance from the applicator at higher power values: at 6W, Δ T > 40 °C at 5mm and ΔT ≅ 5°C at 10mm. ΔT nonlinearly increases with power close to the applicator. Ablated and coagulated tissue volumes have also been measured and experimental results agree with theoretical ones. Despite the absence of data in the current literature on pancreas optical parameters, the model allowed a quite good prediction of thermal effects. The prediction of LITT effects on pancreas is necessary to assess laser dosimetry. © 1964-2012 IEEE.
All Science Journal Classification (ASJC) codes
- Biomedical Engineering
Saccomandi, P., Schena, E., Caponero, M. A., Di Matteo, F. M., Martino, M., Pandolfi, M., & Silvestri, S. (2012). Theoretical analysis and experimental evaluation of laser-induced interstitial thermotherapy in ex vivo porcine pancreas. IEEE Transactions on Biomedical Engineering, 59(10), 2958 - 2964. . https://doi.org/10.1109/TBME.2012.2210895