Classification of tissue biopsies by Raman spectroscopy guided by quantitative phase imaging and its application to bladder cancer.

We present a multimodal label-free optical measurement approach for analyzing sliced tissue biopsies by a unique combination of quantitative phase imaging and localized Raman spectroscopy. First, label-free quantitative phase imaging of the entire unstained tissue slice is performed using automated scanning. Then, pixel-wise segmentation of the tissue layers is performed by a kernelled structural support vector machine based on Haralick texture features, which are extracted from the quantitative phase profile, and used to find the best locations for performing the label-free localized Raman measurements.

Cell and nucleus refractive-index mapping by interferometric phase microscopy and rapid confocal fluorescence microscopy.

We present a multimodal technique for measuring the integral refractive index and the thickness of biological cells and their organelles by integrating interferometric phase microscopy (IPM) and rapid confocal fluorescence microscopy. First, the actual thickness maps of the cellular compartments are reconstructed using the confocal fluorescent sections, and then the optical path difference (OPD) map of the same cell is reconstructed using IPM. Based on the co-registered data, the integral refractive index maps of the cell and its organelles are calculated.