Multivariate analysis of green to ultraviolet spectra of cell and tissue samples

Abstract

This invention relates to methods for processing in vivo skin auto-fluorescence spectra for determining blood glucose levels. The invention also relates to methods of classifying cells or tissue samples or quantifying a component of a cell or tissue using a multivariate classification or quantification model.

1 . A method for processing in vivo skin auto fluorescence spectra emitted by a skin surface of a patient to determine a blood glucose level of the patient comprising the steps of: 
 collecting auto fluorescence spectra emitted from the skin surface of the patient; and    correcting the collected spectra using multivariate analysis to account for skin surface variables.    
     
     
         2 . The method of  claim 1  wherein the multivariate analysis comprises one or more quantification, classification, or data processing techniques selected from the group consisting of: 
 partial least squares, principal component regression, linear regression, multiple linear regression, stepwise linear regression, ridge regression, radial basis functions, linear discriminant analysis, cluster analysis, neural network analysis, smoothing filters, laplacian operators, maximum likelihood estimators, maximum entropy, first and second derivatives, peak enhancement, Fourier self-deconvolution, principal components, and varimax rotations.  
 
     
     
         3 . An instrument for determining a correct glucose level of a patient by measuring in vivo autofluorescence of the patient's skin comprising: 
 means for irradiating the skin with a plurality of excitation wavelengths;    means for collecting a plurality of emitted wavelengths; and    means for analyzing the collected wavelengths to determine a preliminary blood glucose level, said means for analyzing comprising means for correcting the preliminary blood glucose level to account for variations in skin, said means for correcting comprising using one or more multivariate analytical methodologies to determine the correct glucose level of the patient.