Ultrasound already fulfills many criteria as an ideal non-invasive imaging modality for early cancer detection: 1) it is widely available at modest cost, 2) it does not expose patients to ionizing radiation, and 3) it has a very high spatial and temporal resolution. In the Willmann lab, we develop novel molecularly targeted ultrasound contrast agents to molecular targets that are differentially expressed in cancer such as pancreatic and breast cancer compared to benign disease or normal tissues.

Chronic inflammatory diseases such as inflammatory bowel diseases (IBD) require regular and accurate monitoring of the disease's activity for appropriate clinical patient management. While clinical scores often poorly correlate with the disease's activity, novel IBD drugs such as immunosuppressants and immunomodulators with potential substantial side effects have further increased the need for techniques to accurately quantify the disease's activity. In addition, since multiple follow-up exams are needed, often over many years, monitoring should be noninvasive and, above all, patient-friendly. A simple technique that meets all these requirements is not available today. In the Willmann lab, we develop novel non-invasive imaging strategies for accurate and objective quantification and monitoring of inflammation at the molecular level.

Through a process termed "sonoporation," selective insonation of tissue with ultrasound actuates local formation of transient cell membrane microperforations, enhancing blood vessel wall permeability and facilitating the ingress of therapeutic agents into cells. The putative primary mechanism for sonoporation is acoustic cavitation, whereby gas bodies oscillate and eventually collapse, releasing the energy necessary to induce transient cell membrane permeabilization. Ultrasound-mediated drug delivery has shown to be markedly potentiated in the presence of microbubbles, which serve as exogenous cavitation nuclei and reduce the ultrasound energy threshold for sonoporation to occur. In the Willmann lab, we develop and optimize ultrasound equipment, microbubble and nanoparticle design to generate a clinically translatable platform for image-guided drug delivery.