Numerical investigation of nanoparticle-assisted laser-induced interstitial thermotherapy toward tumor and cancer treatments.

In this work, we numerically investigated nanoparticle-assisted laser-induced interstitial thermotherapy for tumor/cancer treatments. The goal of the study was to investigate the therapeutic effects of treatment conditions including laser wavelength, power, exposure time, concentrations of tailored nanoparticles, and optical/thermal properties of the tissue that is under treatment. It was found that using absorbing preferential nanoparticles as the photothermal agent weakens fluence rate distributions in terms of lowering fluence rate peaks and reducing laser penetration depths. However, the local enhancement in laser photon absorption induced by nanoparticles is so significant that the reduced fluence rate will be balanced out, and the eventual medical hyperthermia is greatly prompted by using nanoparticles. Also, the results of numerical simulations indicated that with constant laser illumination, an increase in nanoparticle concentration beyond a certain range has only an insignificant impact on hyperthermia.