Evaluation of accuracy grade in distinct alternatives options for detection of thermal echo-graphic shifts in biomedical phantoms

An analysis of the accuracy level in different alternative techniques for the estimation of increasing temporal displacements in ultrasonic echoes acquired from phantoms (physical and computationally simulated) that mimic biological tissues, is carried out. These time displacements of echoes can be produced, for instance, by a controlled induction of a uniform temperature rising. Average displacement values per °C/mm were obtained applying distinct estimation alternatives under study, and they are presented in this paper. Average error obtained respect to an established reference are shown too. This evaluation is performed considering both: ultrasonic signals acquired experimentally from phantoms specially elaborated to emulate some ultrasonic properties of biological tissue; and pulsed ultrasonic signals simulated by means of computational algorithms that approximate the signal experimental behavior. Results of each evaluated method are discussed and conclusions are given regard those that obtained the major and minor accuracy level.