Analysis of the multiple ultrasound echoes for measurement of cortical bone thickness

Ultrasound is one of the low cost, and accurate techniques used in clinical practice to diagnose bone characteristics such as bone mineral, bone thickness etc. Many researchers had done experiment using ultrasound transducer in many applications. In determination of bone thickness, some researchers successfully implemented pulse echo technique using a pair of transducers (i.e. transmitter and receiver). However, this study focused on the analysis of the multiple echoes in the cortical bone and determined the correct echoes about the cortical bone using pulse echo method. Based on determined echoes, the flight time of echo from surface of the bone to other surface of the bone was determined for measuring the bone thickness. These measurements are carried out using one transducer that reacts as transmitter and receiver at the same time. Then, bone thickness value was compared with manual thickness measurement using vernier caliper for validation of the process. The results showed that ultrasound pulse echo method provided small errors in the cortical bone thickness measurement, 5.31% which is corresponding to 0.05 mm different. The 90% confidential interval for the bone thickness measurement was 0.024 to 0.124.