Liou Jian-Chiun, Peng Chih-Wei, Chen Zhen-Xi
Department of Biomedical Engineering, School of Biomedical Engineering, Taipei Medical University, Taipei 11031, Taiwan.
Micromachines (Basel). 2021 Mar 30;12(4):371. doi: 10.3390/mi12040371.
A cylindrical piezoelectric element and a specific multi-channel circular microelectromechanical systems (MEMS)-transducer array of ultrasonic system were used for ultrasonic energy generation and ablation. A relatively long time is required for the heat to be conducted to the target position. Ultrasound thermal therapy has great potential for treating deep hyperplastic tissues and tumors, such as breast cancer and liver tumors.
Ultrasound ablation technology produces thermal energy by heating the surface of a target, and the heat gradually penetrates to the target's interior. Beamforming was performed to observe energy distribution. A resonance method was used to generate ablation energy for verification. Energy was generated according to the coordinates of geometric graph positions to reach the ablation temperature.
The mean resonance frequency of Channels 1-8 was 2.5 MHz, and the cylindrical piezoelectric ultrasonic element of Channel A was 4.2546 Ω at 5.7946 MHz. High-intensity ultrasound has gradually been applied in clinical treatment. Widely adopted, ultrasonic hyperthermia involves the use of high-intensity ultrasound to heat tissues at 42-45 °C for 30-60 min.
In the ultrasonic energy method, when the target position reaches a temperature that significantly reduces the cell viability (46.9 °C), protein surface modification occurs on the surface of the target.
超声系统采用圆柱形压电元件和特定的多通道圆形微机电系统（MEMS）换能器阵列来产生超声能量并进行消融。热量传导至目标位置需要相对较长的时间。超声热疗法在治疗深部增生组织和肿瘤，如乳腺癌和肝肿瘤方面具有巨大潜力。
超声消融技术通过加热目标表面产生热能，热量逐渐渗透至目标内部。进行波束形成以观察能量分布。采用共振法产生消融能量进行验证。根据几何图形位置的坐标产生能量以达到消融温度。
通道1 - 8的平均共振频率为2.5 MHz，通道A的圆柱形压电超声元件在5.7946 MHz时为4.2546Ω。高强度超声已逐渐应用于临床治疗。超声热疗被广泛采用，涉及使用高强度超声将组织加热至42 - 45°C持续30 - 60分钟。
在超声能量法中，当目标位置达到显著降低细胞活力的温度（46.9°C）时，目标表面会发生蛋白质表面修饰。
