Oct 26, 2018
Green Hall Room 0120, Rodin Auditorium
Photoacoustic imaging (PAI) has seen immense growth, providing unprecedented spatial resolution and functional information at depths ranging from several millimeters up to several centimeters. PAI is a hybrid imaging technology that uses a short-pulsed laser to excite tissue. The resulting acoustic or photoacoustic waves are generated from thermoelastic expansion due to transient rising temperature. They are then measured by ultrasound transducers. The acquired photoacoustic waves are used to image, at ultrasound resolution, the optical absorption distribution, which in turn reveals optical contrast. Optical contrast is directly related to microvessel networks and thus to tumor angiogenesis, a key process for tumor growth and metastasis. In this talk, the PAI application to detect and diagnose ovarian cancers in patients will be demonstrated. Initial data have shown that invasive epithelial ovarian cancers have demonstrated higher and extensive tumor vascularity and lower oxygen saturation than benign and normal ovaries. Two borderline non-invasive serous and one stromal tumor have showed low oxygen saturation in comparison with benign and normal ovaries. The PAI application to detect and diagnose colorectal cancers will be demonstrated. Preliminary data from ex vivo colorectal cancer specimen have shown that malignant colorectal cancers destroy the multi-layer structure of normal colonic tissue and have demonstrated highly disorganized structures as seen in ultrasound and photoacoustic imaging. Other optical imaging techniques on ovarian and colorectal cancer detection and diagnosis will also be discussed.