Michael C. Kolios, PhD
- Ultrasound imaging and therapeutics
- Ultrasound imaging
- Optical Coherence Tomography
- Theranostic agent development
- Heat transfer in tissue
- Thermal Therapies
My research interests are in the application of ultrasound in medicine and the modeling of heat transfer in tissues. I am currently examining the potential of using high frequency ultrasound imaging (20-60MHz) for the detection of cell death. Even though at these frequencies we cannot resolve individual cells, we can examine the ultrasound backscatter from cell ensembles to make inferences about the state of the cells. We have found that the ultrasound backscatter from cells dying either by apoptosis (a form of cell suicide) or necrosis increases, and the frequency dependence of the backscatter power spectra can potentially be used to differentiate between the two, at least in the in vitro systems we have used to date. I am collaborating with researchers at the Sunybrook Hospital in Toronto to determine whether this methodology can also be used in animal tumor models (to detect the death of cancer cells), and we are currently participating in a clinical trial involving cancer patients with superficial tumors. We have developed theoretical models to better understand the backscattering process, and have used experimental systems to examine the backscatter from objects on the scale of cells for which we know their properties. Ultrasonic characterization of cells and cellular components is thus an ongoing interest in the lab. Ultrasound at higher intensities can be used to destroy tissues rather than image them. We have developed theoretical models to estimate temperatures during the heating of tissue using ultrasound or other sources (such as laser), and are currently examining the effect of blood flow on these heating patterns. Furthermore I am investigating the use of an acoustic camera to monitor the treated tissue non-invasively. The acoustic camera records how ultrasound is attenuated rather than detecting the backscatter as conventional ultrasound does. Finally, I have incorporated in my research program optical techniques as a source of new contrast: optical coherence tomography and photoacoustic imaging, which currently form a substantial core of my research program.