Destruction of giant cluster-like vesicles assisted by contrast agent under 2.8-MHz ultrasound irradiation

Localizing tumors and securing resection margins are sometimes difficult especially during laparoscopic surgery for malignant diseases. Therefore, we have developed a tissue marker, which is composed of giant cluster-like vesicles (GCVs) encapsulating near-infrared (NIR) fluorescent liposomes and X-ray contrast agents coated with lipids. The GCVs facilitate localizing tumors preoperatively and intraoperatively because they have superior retention effect in tissue. In addition, the GCVs can work as reservoir of a fluorescent tracer for detecting sentinel lymph nodes if they are destroyed. We propose the method to assess the destruction of GCVs using ultrasound contrast agents (UCAs) and demonstrate the effect.