Focused ultrasound cavitation induced injury and localized atherosclerosis plaques of rabbit abdominal arterial endothelium

Early detection and diagnosis of high-risk or vulnerable plaques can reduce the death rate attributable to atherosclerosis. Many attempts to identify atherosclerosis plaques have focused on in vivo imaging techniques. An animal model with foregone plaque sites will be valuable to evaluate the validity of imaging method. Based on the 'response-to-injury' hypothesis, lesions in the artery's endothelium might be the main mechanism. Therefore, we try to utilize focused ultrasound (FUS) cavitation to generate localized endothelial lesions instead of traditional balloon injury, and thereby induced localized, size-controlled plaques combined with high cholesterol diet. In this paper, rabbit abdominal aortas were processed by phase-shifted nanodroplets (PSND) enhanced FUS cavitation and balloon injury separately. Evans blue stained endothelial lesions were observed in both balloon and FUS cavitation injury. The injury regions caused by balloon were distributed on the whole vessel wall, while cavitation injuries were just located at US exposure sites. Additionally, the lesions with different sizes can be generated by adjusting US intensity, exposure time, etc. Furthermore, rabbits were developed plaques using high fat feeding, balloon injury plus fat feeding, and cavitation injury plus fat feeding separately. As a result of cavitation injury, the induced plaques were size-controlled and localized at the predictable site, while the plaque induced by balloon injury occurs randomly within the injury region. Therefore, cavitation injury might become an alternative and potential strategy to develop a localized and controllable atherosclerosis model.