Raman spectroscopy for less invasive and online medical applications

Applications of optical spectroscopy techniques, such as Fourier Transform Infrared (FTIR), Raman, and fluorescence, in biology and medicine have been actively pursued in recent times. Since optical spectroscopic techniques are very sensitive to biochemical composition of the sample under study, they are being pursued as non invasive analytical methodologies. Early transformation from healthy to diseased states is attributed to biochemical changes within tissue. Efficacy and potential applications of optical spectroscopic techniques in disease diagnosis has been well demonstrated. Another attractive feature of optical spectroscopic methods is that data are amenable to multivariate statistical tools. Various statistical techniques have been successfully deployed to exploit subtle differences in Raman spectra for diagnostic purpose. Principal Component Analysis (PCA) and its derivatives like Linear Discriminate Analysis (LDA) and logistic regression are some of the widely used methods. Among optical spectroscopic methods Raman spectroscopy can provide detailed information about chemical composition of the tissue under study and since progression of a disease is accompanied by chemical changes, it can provide the physician with valuable diagnostic and prognostic information. Most important attribute of Raman spectroscopy is its in vivo applications, since light can be delivered and collected rapidly via optical fibres which can be incorporated into catheters, endoscopes, cannulas and needles. In the present talk we discuss role of Raman spectroscopy in diagnosing cancers. We will emphasize on less invasive and non invasive diagnostic applications.