Imaging subcellular scattering contrast by using combined optical coherence and multiphoton microscopy.

The structural origin of scattering contrast from single cells is examined by using a combined optical coherence and multiphoton microscope based on a 12 fs Ti:sapphire source and a 0.95 NA objective. High-resolution coherence-gated scattering images from single cells are coregistered and compared with two-photon-excited fluorescence images. Scattering contrast is observed from mitochondria, plasma membrane, actin filaments, and the boundary between cytoplasm and nucleus. There is little contribution to scattering from regions inside the nuclear core. These results confirm that light scattering signals from specific subcellular structures can be visualized by using coherent reflectance geometry.