Fiber-optic laser-ultrasound transducer using carbon nanoparticles for intravascular sonothrombolysis
Intravascular ultrasound thrombolysis has shown its advantages in the improved treatment rate compared with traditional administration of thrombolytic agents, and a safer treatment procedure compared with mechanical drilling methods. However, the method still suffers from the long treatment time. Although recent studies have shown progress in miniaturizing intravascular piezoelectric ultrasound transducers to improve the clot lysis rate, the transducer's size control, fabrication and packing are still complicated. On the other hand, laser generated ultrasound (LGU) has a relatively simple structure and can be adapted for expediting thrombolysis with its high acoustic pressure. However, there is a lack of studies on the intravascular LGU transducers. Therefore, in this study, we designed and fabricated an intravascular laser ultrasound transducer on an optical fiber. We characterized the transducer's performance by measuring its output pressure. Lastly, the transducer's thrombolysis rate was estimated in vitro. The preliminary test result showed on average a 32% reduction in the clot mass after a 30-min treatment with our transducer, demonstrating the feasibility of the sonothrombolysis use.
