Title: Ex vivo analysis of the oral epithelium by high-wavenumber Raman spectroscopy

Authors: Roberto Valdés; Stefan Stefanov; Stefano Chiussi; Pío González; Miriam López-Álvarez

Addresses: New Materials Group, Applied Physics Department, Institute of Biomedical Research (IBI), University of Vigo, 36310, Vigo, Spain; Department of Otolaryngology and Head and Neck Surgery, Hospital Povisa, 36211, Vigo, Spain ' New Materials Group, Applied Physics Department, Institute of Biomedical Research (IBI), University of Vigo, 36310, Vigo, Spain ' New Materials Group, Applied Physics Department, Institute of Biomedical Research (IBI), University of Vigo, 36310, Vigo, Spain ' New Materials Group, Applied Physics Department, Institute of Biomedical Research (IBI), University of Vigo, 36310, Vigo, Spain ' New Materials Group, Applied Physics Department, Institute of Biomedical Research (IBI), University of Vigo, 36310, Vigo, Spain

Abstract: Raman spectroscopy at wavenumber region of 400-1800 cm−1 is an already proved promising technology for objective clinical evaluation of biological tissues to obtain their molecular fingerprint. The study of the high-wavenumber region (2800-3100 cm−1) is also of interest to significantly shorten the diagnosis time due to the intense Raman signal in a narrower range. This work studies parameters dependence, Raman saturation in depth and repeatability of tissue measurements at this region and proposes three indices for quantitative diagnose in oral epithelium. Sixteen oral mucosa biopsies in different thicknesses were evaluated in varying laser powers. The non-saturation of Raman signal up to 120 μm in depth was demonstrated. Three peaks (2874, 2926, 3056 cm−1) attributed to functional groups of interest in oral mucosa were identified from the Raman band deconvolution. The high-wavenumber correspondence with the fingerprint region (400-1800 cm−1) was proven and three diagnose indices proposed to quantitatively evaluate oral epithelium tissue in routinely clinical practice.

Keywords: Raman spectroscopy; high-wavenumber region; fingerprint region; clinical diagnosis; quantitative diagnose indices; non-invasive methodologies; biopsies; oral mucosa; epithelium; head and neck diseases; squamous cell carcinoma; severe dysplasia; inflammatory lesions.

DOI: 10.1504/IJBET.2017.084665

International Journal of Biomedical Engineering and Technology, 2017 Vol.24 No.2, pp.154 - 168

Received: 26 Feb 2016
Accepted: 16 May 2016

Published online: 20 Jun 2017 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article