Krasovitski Boris, Kimmel Eitan, Sapunar Michal, Adam Dan
The Department of Biomedical Engineering Technion, Haifa, Israel.
Ultrasound Med Biol. 2004 Jun;30(6):793-802. doi: 10.1016/j.ultrasmedbio.2004.03.010.
Ultrasound (US) contrast agents (UCA) consist of artificial encapsulated microbubbles filled with low-diffusivity gas. This study evaluated, both experimentally and theoretically, the behavior of a cloud of encapsulated microbubbles while the surrounding pressure was modified within the physiological range. The theoretical analysis included calculation of US attenuation caused by a bubble cloud. The radius and gas content of each bubble were determined from a solution of a diffusion problem. Shell permeability and rigidity were taken into account. Both experiments and theory demonstrated that, for fixed ambient pressures, higher pressures result in increased rate of attenuation decay. Pulsatile ambient pressure induces pulsations of attenuation of the same frequency. In general, theoretical predictions are in good agreement with experimental data.
超声（US）造影剂（UCA）由填充有低扩散性气体的人工封装微泡组成。本研究通过实验和理论分析，评估了在生理范围内改变周围压力时，封装微泡云团的行为。理论分析包括计算气泡云团引起的超声衰减。每个气泡的半径和气体含量由扩散问题的解确定。考虑了壳的渗透性和刚性。实验和理论均表明，在固定的环境压力下，较高的压力会导致衰减率增加。脉动的环境压力会引起相同频率的衰减脉动。总体而言，理论预测与实验数据吻合良好。
