Suitability of the echo-time-shift method as laboratory standard for thermal ultrasound dosimetry

Ultrasound therapy is a promising, non-invasive application with potential to significantly improve cancer therapies like surgery, viro- or immunotherapy. This therapy needs faster, cheaper and more easy-to-handle quality assurance tools for therapy devices as well as possibilities to verify treatment plans and for dosimetry. This limits comparability and safety of treatments. Accurate spatial and temporal temperature maps could be used to overcome these shortcomings. In this contribution first results of suitability and accuracy investigations of the echo- time-shiftmethod for two-dimensional temperature mapping during and after sonication are presented. The analysis methods used to calculate time-shiftswere a discrete frame-to-frame and a discrete frame-to-base-frame algorithm as well as a sigmoid fit for temperature calculation. In the future accuracy could be significantly enhanced by using continuous methods for time-shiftcalculation. Further improvements can be achieved by improving filtering algo...