Enhancing cavitation-based anti-vascular and thrombolysis therapy

Photo-sono therapy (PST) has recently emerged as a non-invasive approach to treating diseases such as thrombosis. Through the synchronized application of nanosecond laser pulses and ultrasound bursts, micro-bubbles form and collapse in the target, generating cavitation shockwaves that facilitate blood clot breakdown and tissue ablation.

While PST has improved upon traditional high-intensity focused ultrasound therapy in both precision and cavitation threshold, Song et al. found a way to enhance its performance.

In their research, they integrated dual-frequency sonication into PST to achieve desired therapeutic outcomes.

“Our approach provides a pathway for safer, more precise clinical cavitation-based therapies,” said author Zhongping Chen. “By demonstrating enhanced efficacy at lower energy, we addressed key safety concerns regarding thermal damage, potentially accelerating the translation of PST from the lab to the clinic.”

Furthermore, in simulations of single bubble dynamics under varying laser and acoustic conditions, the researchers found that dual-frequency PST requires approximately half the cavitation threshold of single-frequency PST.

To assess thrombolytic performance, the researchers used optical coherence tomography (OCT) to quantitatively examine ex vivo blood vessels and blood clot phantoms treated with cavitation-based therapies. Subsequent 3D structural reconstructions reveal that dual-frequency PST significantly outperforms other ultrasonic approaches; in vivo anti-vascular treatments in rabbit ears match these results.

The authors plan to further advance the effectiveness, precision, and energy efficiency of dual-frequency PST.

“Our future work will refine simulations with realistic light propagation and thermal effects,” said Chen. “We will optimize the integrated PST-OCT system to be more compact, improve the treatment workflow, and develop personalized protocols for different vessel sizes and depths for clinical translation.”

Source: “Enhanced photo-sono therapy with dual-frequency ultrasound,” by Yuchen Song, Shuang Wei, Haibin Zou, Jingyi Wang, Fengyi Zhang, Qifa Zhou, Yun Jing, and Zhongping Chen, APL Bioengineering (2025). The article can be accessed at https://doi.org/10.1063/5.0288979 .