Acoustic Characterisation of Konjac Glucomannan Gei as a Medical Phantom

摘要

Acoustic properties are the main criteria to evaluate the compatibility of tested materials as a medical phantom. We determined the acoustic properties of konjac glucomannan (KGM) gel to verify its compatibility as a medical phantom. The acoustic properties measurement employed ultrasonic insertion technique and utilized two identical transducers of 5 MHz center frequencies. One KGM gel block with 5.62 mm thickness was used as sample to determine its longitudinal speed, acoustic impedance and attenuation coefficient at three different water temperatures; (21.5 ±0.1), (22.5 ± 0.1) and (23.5 ± 0.1)℃. Findings indicated that its longitudinal speed and acoustic impedance increased from (1495 ± 1) to (1499 ± 1) m s~(-1) and (1.555 ± 0.001) to (1.559 ± 0.001) x 10~6 kg m~(-2)s~(-1) as the water temperature increased from (21.5 ± 0.1) to (23.5 ± 0.1)℃. It also indicated that its attenuation coefficient varied around (0.1303 ± 0.0107) to (0.1373 ± 0.0103) dB cm~(-1) with increasing water temperature. KGM gel is compatible to be a medical phantom since its acoustic properties are comparable to the acoustic properties of human soft tissue.