METHODS: All subjects (nine women) provided written informed consent to participate in this Institutional Review Board-approved study. A total of 10 fibroids were treated using MRgHIFU surgery with real-time temperature monitoring during both heating and cooling periods. The local thermal conductivity was determined by analyzing the spatiotemporal spread of temperature during the cooling period.
RESULTS: The thermal conductivity of MRgHIFU-treated uterine fibroids was 0.47 ± 0.07 W·m(-1) ·K(-1) (range: 0.25∼0.67 W·m(-1) ·K(-1) ) which is slightly lower than the reported value for skeletal muscle at temperatures of <40°C (0.52 to 0.62 W·m(-1) ·K(-1) ).
CONCLUSIONS: It is possible to estimate the thermal conductivity of uterine fibroids in vivo from the spatiotemporal spread of temperature around the HIFU focus during the cooling period.