Optical Tools for High Resolution Imaging of Cerebral Hemodynamics

Date(s) - 12/16/2013
4:00 pm

Dr. Andrew K. Dunn, Associate Professor, Biomedical Engineering, University of Texas at Austin


During ischemic stroke, oxygen delivery in interrupted to a region of the brain resulting in a complex cascade of hemodynamic and cellular events that ultimately leads to cell death and tissue damage. Although recent advances in high resolution in vivo imaging have enabled some aspects of this cascade to be visualized dynamically, the detailed changes in blood flow and oxygenation during stroke remain poorly understood. This talk will describe two new developments in optical imaging techniques for high resolution imaging of cortical hemodynamics and their application to animal models of stroke and clinical translation to neurosurgery. The first, laser speckle contrast imaging, enables real-time visualization of blood flow during neurosurgery, monitoring of clot formation in animal models of stroke, and chronic tracking of blood flow changes to assess recovery from brain injury. The second, two-photon phosphorescence lifetime microscopy, allows determination of oxygen levels in single, subsurface blood vessels with three-dimensional micron scale resolution. When combined together, these imaging methods provide unprecedented levels of in vivo information about the microvascular alterations in the brain following diseases such as stroke.