Premium
Evaluation of a confocal R aman probe for pathological diagnosis during colonoscopy
Author(s) -
Wood J. J.,
Kendall C.,
Hutchings J.,
Lloyd G. R.,
Stone N.,
Shepherd N.,
Day J.,
Cook T. A.
Publication year - 2014
Publication title -
colorectal disease
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.029
H-Index - 89
eISSN - 1463-1318
pISSN - 1462-8910
DOI - 10.1111/codi.12664
Subject(s) - medicine , colonoscopy , pathological , confocal , colorectal cancer , cancer , geometry , mathematics
Aim Raman spectroscopy of human tissue can provide a unique biochemical ‘fingerprint’ that alters with disease progression. Light incident on tissue is scattered and may be altered in wavelength, which can be represented as a R aman spectrum. A confocal fibreoptic R aman probe designed to fit down the accessory channel of a colonoscope has been constructed. This in‐vitro study evaluated the accuracy of pathological diagnosis in the colon using probe‐based R aman spectroscopy. Method Biopsy samples were collected at colonoscopy, snap frozen and stored at −80°C. Raman spectra with 10‐s and 1‐s acquisition periods were measured with the probe tip in contact with the mucosal surface of thawed specimens. Mathematical modelling using principal component analysis followed by linear discriminant analysis was used to correlate R aman spectra with histopathological diagnoses. Results Three‐hundred and seventy‐five R aman spectra were measured from a total of 356 colon biopsies (81 of normal colon mucosa, 79 of hyperplastic polyps, 92 of adenomatous polyps, 64 of adenocarcinoma and 40 of ulcerative colitis) from 177 patients. Spectral classification accuracies comparing pathology pairs ranged from 72.1 to 95.9% for 10‐s acquisitions and from 61.5 to 95.1% for 1‐s acquisitions. For a three‐group model of normal, adenomatous and adenocarcinoma tissue, accuracies were 74.1% for 10‐s acquisitions and 63.5% for 1‐s acquisitions. Conclusion The confocal R aman probe system can distinguish between different colorectal pathologies. The probe has potential to establish R aman spectroscopy as a clinical tool for instant diagnosis at colonoscopy.