Real-time depth-resolved Raman endoscopy for in vivo diagnosis of dysplasia in Barrett's esophagus

Abstract

Raman spectroscopy is a vibrational analytic technique sensitive to the changes in biomolecular composition and conformations occurring in tissue. With our most recent development of depth-resolved near-infrared (NIR) Raman endoscopy integrated with on-line diagnostic algorithms, in vivo real-time epithelial diagnostics has been realized under multimodal wide-field imaging (i.e., white- light reflectance (WLR), narrow-band imaging (NBI), autofluorescence imaging (AFI)) modalities. A selection of 43 patients who previously underwent Raman endoscopy (n=146 spectra) was used to render a robust model based on partial least squares - discriminant analysis (PLS-DA) for diagnosis of dysplasia in Barrett's esophagus. The Raman endoscopy technique was validated prospectively on 2 new esophageal patients for in vivo tissue diagnosis. The Raman endoscopic technique could identify esophageal high-grade dysplasia in vivo with an accuracy of 85.9% (sensitivity: 91.3% (21/23): specificity 83.3% (40/48)) on spectrum basis. This study realizes for the first time depth-resolved Raman endoscopy for real-time in vivo diagnosis of dysplasia in Barrett's epithelium at the biomolecular level. © 2013 Copyright SPIE.