Thermal dosimetry in porcine tissue: choice of laser wavelength for LITT

Summary form only given. Laser interstitial thermotherapy (LITT) is a minimally invasive procedure for the treatment of small tumors of the breast. During LITT, heat is produced through the localized absorption of infrared laser radiation by tissue surrounding the treatment site. A fiber probe is used to transmit the light to the tumor site, located stereotactically by radiomammography under the control of the oncologist. Since the goal of the treatment is to induce localized cell death as a result of hyperthermia, the effectiveness of the treatment and a suitable treatment endpoint is observed by the measurement of the resultant temperature distribution in the region of interest. Ongoing studies have examined i) the thermal and light distribution of LITT treatment as a function of applied laser power and duration, ii) the thermal and light distribution of diffusing light fibers of different designs and geometries, iii) the thermal dosimetry in ex-vivo porcine and human breast tissue, in-vivo porcine tissue and a range of tissue phantoms of controlled or known optical properties and iv) the thermal dosimetry of tissue models as a function of wavelength of candidate treatment lasers