Poster abstracts

Poster number 30 submitted by Jiwei Huang

Heat-sensitive microbubbles for imaging and assessment of cancer ablation margin

Jiwei Huang (Biophysics Graduate Program), Dr. Jeff Xu (Biomedical Engineering), Dr. Ronald Xu (Biomedical Engineering)

Abstract:
Thermal ablation therapies represent a group of minimally invasive cancer treatments which use heat to destroy the tumor. They have the advantages of minimal trauma, minimal complication, outpatient treatment, fast recovery, and fast return to normal activities. However, cancer ablation therapies are still considered highly investigational because of controversial issues associated with clinical efficacy, long-term local recurrence rate, and disease-free survival. These issues are due to the lack of appropriate imaging and assessment of cancer ablation margin during thermal ablation.
The proposed study is focused on the development of a heat-sensitive microbubble (HSM) agent for imaging and assessment of cancer ablation margin. The HSM agent, with a size around 2µm and comprising a core of liquid perfluorocarbon (PFC) and a shell of biodegradable poly lactic-co-glycolic acid (PLGA), will be fabricated using an emulsion evaporation method and a coaxial electro-hydrodynamic atomisation method. The agent will be delivered to the tumor site prior to ablation. During cancer ablation, thermal energy applied to the tumor tissue will induce the expansion of HSMs due to the evaporation of PFC within HSMs. Specific fabrication designs, including adjusting HSM’s size and shell thickness, will ensure the expansion of HSMs occur at the lethal thermal dose for tumor. The expansion of HSMs will significantly increase the ultrasound (US) contrast, and enable direct imaging and assessment of the ablation margin by a clinical US probe. This imaging method will be demonstrated on a tissue phantom and an HSM-perfused porcine kidney model.

References:
1. J. Huang, J. Xu, and R. Xu, Heat-sensitive microbubbles for intraoperative assessment of cancer ablation margins, Biomaterials, 31 (2010) 1278–1286

2. J. Huang, J. Xu, and R. Xu, Microfabrication of heat-sensitive microbubbles for cancer ablation margin assessment, Journal of Endourology, 2009, 23(6): 105

3. R. Xu, J. Xu, J. Huang, Invention disclosures: Targeted Delivery of Heat-Sensitive Nanobubbles and Microbubbles for the Assessment of Thermal Ablation Margins in Breast Cancer and other Malignancies. Invention disclosure #09090, OSU Technology Licensing & Commercialization Office.

Keywords: Microbubble, Thermal ablation margin, Intraoperative imaging