Acoustic Characterisation of Konjac Glucomannan Gel as a Medical Phantom

Abstract

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) °C. 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) × 106 kg m-2 s-1 as the water temperature increased from (21.5 ± 0.1) to (23.5 ± 0.1) °C. 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.

Effect of Temperature and Frequency on the Acoustic Properties of Konjac Glucomannan-Agar Gels as Tissue Mimicking Materials

“…Tissue mimicking materials (TMMs) are materials that mimic the acoustic properties of human tissues [1][2]. Thus, the values of acoustic properties are important to determine the compatibility of a tested material as a TMM [2][3]. The acoustic properties of human tissues are highly dependent on temperature and frequency.…”

“…Recently, researchers studied the potential of new ingredients as TMMs like gellum gum hydrogel [13] and Konjac-Carrageenan hydrogel [14]. In 2017, Mat Daud, Rohani and Jaafar determined the longitudinal speed, acoustic impedance and attenuation coefficient of Konjac Glucomannan (KGM) gel [2]. The result indicated that the KGM gel was compatible to be a TMM since its acoustic properties were in the range of the acoustic properties of human soft tissue.…”

A computerized system based on an alternative pulse echo immersion technique for acoustic characterization of non-porous solid tissue mimicking materials

“…In 2013, a computerized system was developed, based on the LeCroy Wave Series digital oscilloscope, for online measurement of the acoustic properties of TMMs [8]. This system is based on an ultrasonic insertion technique (UIT) that uses two identical transducers aligned with one another [9,10]. Therefore, a sample has to be carefully inserted between transmitter and receiver such that its surface is perpendicular to both transducers, in order to ensure the accuracy of measurement [9][10][11].…”

“…This system is based on an ultrasonic insertion technique (UIT) that uses two identical transducers aligned with one another [9,10]. Therefore, a sample has to be carefully inserted between transmitter and receiver such that its surface is perpendicular to both transducers, in order to ensure the accuracy of measurement [9][10][11]. Furthermore, the developed system requires ultrasound pulse transmission in distilled water as the calibration procedure and the water temperature measurement, to calculate the acoustic properties of samples [8,9].…”

“…It also requires measurement of the water temperature in order to calculate the acoustic properties of samples [5,13]. According to previous researches, the acoustic properties of TMMs are highly dependent on the water temperature [9,[14][15][16]. Therefore, fluctuation in or inaccurate measurement of the water temperature could affect the accuracy of the measurement of the acoustic properties of TMMs.…”