Method for the detection of cellular abnormalities using infrared spectroscopic imaging

摘要

This invention teaches a method to identify cellular abnormalities which are associated with disease states. In one aspect, the invention is a method to distinguish premalignant and malignant stages of cervical cancer from normal cervical cells. The method utilizes infrared (IR) spectra of exfoliated cervical cells which are dried on an infrared transparent matrix and scanned at the frequency range from 3000-950 cm-1. The identification of samples is based on establishing a calibration using a representative set of spectra of normal, dysplastic and malignant specimens. During the calibration process, multivariate techniques such as Principal Component Analysis (PCA) and/or Partial Least Squares (PLS) are used. PCA and PLS reduce the data based on maximum variations between the spectra, and generate clusters in a multidimensional space representing the different populations. The utilization of Mahalinobis distances, or linear regression (e.g., Principle Component Regression on the reduced data from PCA) form the basis for the discrimination. This method is simple to use and achieves statistically reliable distinction between the following groups of cervical smears: normal (individuals with no prior history of dysplasia), dysplasia and malignant samples. Further, this invention discloses a method to obtain the IR spectrum of individual cervical cells fixed on an infrared transparent matrix and to use the spectra o the individual cells in the method described above. In an additional aspect, the invention is a method for using vibrational spectroscopic imaging to distinguish between normal and diseased cells.