title: Design of microprobe for accurate thermal treatment of tumor.
abstract: Thermal treatment has become an alternative modality for cancer treatment. Low temperature freezing and high temperature heating kill tumor cells effectively through direct and indirect injuries by biochemical and physical stresses. Hyperthermia at a mildly elevated temperature has also been reported to induce biochemical alternations to kill tumor cells and to stimulate immunological response to prevent metastasis. The comprehensive multi-scale biological responses to different thermal history experienced demand an accurate temperature control of the thermal system used for such a treatment. A thermal system was built in our lab utilizing RF heating and liquid nitrogen cooling through a needle probe. In practice, difficulties involved in temperature measurement for in vivo monitoring and control of thermal input through two-phase LN2 flow inside the probe compromise the treatment outcome. To ensure an accurate temperature control, a new model was developed to study the dynamic freezing capacity of the cryo-probe by accounting for the probe shape and dimensions. The model was validated by experiments and used to predict the freezing processes under different conditions. Numerical simulation results showed that combined with RF heating, the system could be used to perform different treatment protocols with an accurate temperature control.
authors.affiliation: Department of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Chen
authors.forename: Aili
authors.initials: A
authors.lastname: Zhang
authors.forename: Zhanghao
authors.initials: Z
authors.lastname: Cai
authors.forename: Jianqi
authors.initials: J
authors.lastname: Sun
authors.forename: Lisa X
authors.initials: LX
authors.lastname: Xu
mesh_terms: D003080:Cold Temperature; D017679:Cryotherapy / Q000295:instrumentation*; D004867:Equipment Design; D005782:Gels; D006358:Hot Temperature; D006801:Humans; D006979:Hyperthermia, Induced / Q000295:instrumentation*; D008962:Models, Theoretical; D009369:Neoplasms / Q000628:therapy*; D009584:Nitrogen; D013821:Thermometers
chemical_list: D005782:Gels; D009584:Nitrogen