Estimating the ultrasound attenuation coefficient using complementary Golay codes

Accurate evaluation of ultrasonic wave attenuation is important in many medical applications of ultrasound. The aim of this work is to present a thorough analysis of the effectiveness of using complementary Golay coded sequences (CGCS) during the evaluation of ultrasound attenuation in tissue-like materials, especially at greater depths or at high attenuation. In order to compare the results of the attenuation measurement with the use of CGCS transmission and a short two sine cycles pulse, ultrasound backscattered from medium with predefined attenuation of 0.3, 0.7 and 2 dB/[MHz × cm] were simulated. Also for the same transmission signals, measurements of ultrasound echoes scattered in the tissue phantom with an attenuation of 0.5 dB/[MHz × cm] were performed. In the case of numerically simulated data, for the CGCS excitation, the maximum depth for which the attenuation was correctly determined increased from 55 mm to 80 mm for the 0.7 dB/[MHz × cm] phantom and from 20 mm to 50 mm for the 2 dB/[MHz × cm] phantom compared to excitation of the transducer with a short two sine cycles pulse. When the measurement data obtained using the tissue phantom was used to estimate the attenuation coefficient, the relative error was determined to be 6% and 16% for the depths of 10 mm and 40 mm for the short two sine cycles pulse excitation, respectively. Corresponding values for CGCS excitation and considered depths were 2% and 4%. The use of CGSC sequence during attenuation measurements increases measurement accuracy and can improve medical diagnostic techniques.