报告摘要：Optical microscopes have been an indispensible tool for biological research and clinical applications. For example, optical coherence tomography (OCT) can provide a penetration depth up to a few millimeters by the use of coherence gating; Multi-photon microscopy (MPM) uses ultra-short laser pulses to achieve selective excitation and an imaging depth up to 700 microns. We have been developing a fluorescence microscopy method, Focal Modulation Microscopy, that offers a penetration depth comparable to OCT and MPM, while compatible with most fluorescence dyes. Preliminary experiments have demonstrated the feasibility of our approach and improved image quality over conventional confocal microscopy for deep tissue imaging.

Non-invasive optical imaging of large human organs, such as human brain and breast, is desirable for disease diagnosis and treatment monitoring. However, human soft tissues are highly scattering for visible and near-infrared light. We are interested in time-resolved diffuse optical tomography (DOT), a technique that is based on measuring the pathlength resolved diffusive light intensity on tissue surfaces We have developed a novel approach to implement fast measurement with high signal to noise ratio. A prototype time-resolved DOT system has been built and characterized with phantom experiments. Preliminary studies with healthy human subjects were conducted and the results will serve as the baseline for future clinical experiments with breast cancer patients.