Ultrasound attenuation estimation in soft tissue using the entropy difference of pulsed echoes between two adjacent envelope segments.

In this paper, we describe a new method of estimating the ultrasound attenuation coefficient of soft tissue based on the entropy difference between two adjacent envelope segments of narrowband ultrasound pulse echoes. Assuming uniform attenuation in the region under investigation, the attenuation is estimated by minimizing the difference of entropies in the two segments as the attenuation is continuously compensated for. The simulation and experimental results with a tissue equivalent (TE) phantom show that the proposed estimator is quite robust to receiver noise and requires considerably less data length as compared with conventional methods. At present, an experimental result with a TE phantom shows that a resolution of 10 mm x 10 mm can be attained with echoes from a depth of 3 cm using a 2.25 MHz transducer.