Stride E, Saffari N
Department of Mechanical Engineering, University College London, Torrington Place, London WC1E 7JE, UK.
Ultrasonics. 2004 Apr;42(1-9):907-13. doi: 10.1016/j.ultras.2003.12.014.
The development of coated microbubble ultrasound contrast agents for use in imaging applications and as carriers in drug and gene delivery applications has intensified the need for a clear understanding of their behaviour and potential bioeffects. Previous studies have focused on the risks posed by unencapsulated bubbles as representing the "worst case scenario". They have concluded that the risk of thermal damage should be minimal provided the threshold for inertial cavitation is not exceeded. However, these treatments have ignored the heating effects due to viscous dissipation in the coatings of contrast agent particles. Simulations indicate that the temperature rise due to this process may be sufficient to generate harmful bioeffects even under conventionally "safe" insonation conditions. The implications of these findings and strategies for addressing the risks posed by contrast agents are discussed.
用于成像应用以及作为药物和基因递送应用载体的包被微泡超声造影剂的发展，加剧了人们对其行为和潜在生物效应进行清晰了解的需求。先前的研究集中于未封装气泡所带来的风险，将其视为“最坏情况”。这些研究得出结论，只要不超过惯性空化阈值，热损伤风险就应最小。然而，这些研究忽略了造影剂颗粒包衣中粘性耗散所导致的加热效应。模拟表明，即使在传统的“安全”超声照射条件下，这一过程导致的温度升高也可能足以产生有害的生物效应。本文讨论了这些发现的意义以及应对造影剂所带来风险的策略。
