On the assessment of time-shift variations from backscattered ultrasound for large temperature changes in biological phantoms

This work reports the assessment of time-shifts (TS) from backscattered ultrasound (BSU) signals when large temperature variations (up to 15 ∘C) were induced in a gel-based phantom.The results showed that during cooling temperature is linear with TS at a rate of approximately 74 ns/∘C. However during a complete heating/cooling cycle, the relation is highly non-linear.This can be explained by the fact that during cooling the temperature distribution is more uniform. Another problem to report is that TS is very sensitive to external movements.