Lasers in Surgery and Medicine 1963-74 (1996) Spectroscopic Diagnosis of Cervical lntraepithelial Neoplasia (CIN) In Vivo Using Laser-Induced Fluorescence Spectra at Multiple Excitation Wavlengths

Background and Objective: The diagnostic contribution of cervi-cal tissue fluorescence spectra acquired in vivo at 380 and 460 nm excitation were analyzed using a general multivariate statistical algorithm. Materials and Methods: The primary steps of the algorithm are to: (1) preprocess data to reduce interpatient and intrapatient variation of tissue spectra from the same diagnostic category, without a priori information, (2) dimensionally reduce the pre-processed spectral data using Principal Component Analysis, and (3) develop a probability based classification scheme based on logistic discrimination using the diagnostically useful princi-pal components. The algorithm was tested on cervical tissue spectra acquired from 165 sites at 380 nm excitation and from 147 sites at 460 nm excitation. A retrospective and propsective esti-mate of the algorithm’s performance was determined