title: Digital de-waxing on FTIR images.
abstract: This paper presents a procedure that digitally neutralizes the contribution of paraffin to FTIR hyperspectral images. A brief mathematical derivation of the procedure is demonstrated and applied on one normal human colon sample to exemplify the de-waxing procedure. The proposed method includes construction of a paraffin model based on PCA, EMSC normalization and application of two techniques for spectral quality control. We discuss every step in which the researcher needs to take a subjective decision during the de-waxing procedure, and we explain how to make an adequate choice of parameters involved. Application of this procedure to 71 hyperspectral images collected from 55 human colon biopsies (20 normal, 17 ulcerative colitis, and 18 adenocarcinoma) showed that paraffin was appropriately neutralized, which made the de-waxed images adequate for analysis by pattern-recognition techniques such as k-means clustering or PCA-LDA.
authors.affiliation: Universidade de São Paulo, Avenida dos Bandeirantes, 3900, Ribeirão Preto, SP, Brazil. l.b@usp.br.
authors.forename: Fabrício Augusto
authors.initials: FA
authors.lastname: de Lima
authors.forename: Cyril
authors.initials: C
authors.lastname: Gobinet
authors.forename: Ganesh
authors.initials: G
authors.lastname: Sockalingum
authors.forename: Sérgio Britto
authors.initials: SB
authors.lastname: Garcia
authors.forename: Michel
authors.initials: M
authors.lastname: Manfait
authors.forename: Valérie
authors.initials: V
authors.lastname: Untereiner
authors.forename: Olivier
authors.initials: O
authors.lastname: Piot
authors.forename: Luciano
authors.initials: L
authors.lastname: Bachmann
mesh_terms: D001706:Biopsy; D016000:Cluster Analysis; D006801:Humans; D007089:Image Enhancement; D007090:Image Interpretation, Computer-Assisted; D010232:Paraffin; D017550:Spectroscopy, Fourier Transform Infrared; D014885:Waxes
chemical_list: D014885:Waxes; D010232:Paraffin