Diffuse optical spectroscopy and imaging (DOSI) is a class of non-invasive near-infrared imaging techniques based upon measuring the wavelength-dependent absorption and (reduced) scattering optical properties of living tissues. In the far-red to near-infrared optical therapeutic window, these optical properties provide information about deep (several cm) tissue composition, structure, and oxygen metabolism. In particular, DOSI is capable of quantifying tissue concentrations of the physiologically relevant molecules oxyhemoglobin, deoxygenated hemoglobin, lipid, and water, as well as structural parameters including cellular size and density (obtained from scattering spectra). The significance and applicability of these and other DOSI biomarkers collected with research devices have been demonstrated in numerous clinical studies of oncology, cardiovascular assessment, exercise physiology, and neuroscience.
In this presentation, I will discuss how DOSI has shown promise in the field of breast oncology for risk assessment, screening, differential diagnosis of benign and malignant lesions, and predicting and monitoring response to chemotherapy treatment. DOSI biomarkers vary significantly in abundance and molecular state between breast cancer and normal tissue and unique cancer-specific absorption signatures have been observed. Finally, I will demonstrate how we are working to translate this promising technology to clinical practice and my vision for the future.
Dr. Thomas O'Sullivan has been an assistant professor in the Department of Electrical Engineering at the University of Notre Dame since 2016. Prior to that he was the Director of the Diffuse Optical Spectroscopy and Imaging Laboratory at the Beckman Laser Institute at the University of California, Irvine and a U.S. Department of Defense Breast Cancer Research Program Postdoctoral Fellow. He received the B.S. degree in Electrical Engineering from Northwestern University in 2005 and the M.S. and Ph.D. in Electrical Engineering from Stanford University (advisor: James S. Harris) in 2007 and 2011, respectively. Dr. O'Sullivan is engaged in translational biomedical research based upon the development and application of deep tissue optical imaging and sensing. In particular, Dr. O'Sullivan's lab is advancing diffuse optical spectroscopy and imaging, which allows for contrast-free quantitative measurements of tissue architecture and metabolic function. This work, while relevant to many diseases, is presently focused on applications in breast cancer including risk assessment, screening, differential diagnosis, and predicting individual response to chemotherapy treatment.