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PubMed · 9786112

Colonic polyp differentiation using time-resolved autofluorescence spectroscopy.

M A Mycek·K T Schomacker·N S Nishioka
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Abstract

BACKGROUND: Steady-state autofluorescence spectroscopy has been examined previously as a technique for distinguishing polyp types during colonoscopy. Although time-resolved methods have shown promise for tissue diagnosis in vitro, they have never been applied endoscopically. The aim of this study was to examine the feasibility of performing time-resolved autofluorescence spectroscopy in vivo and to determine the diagnostic accuracy of the technique as applied to colonic dysplasia. METHODS: A time-resolved spectrometer was used to measure the spectrally resolved transient decay of laser-induced autofluorescence emission from colonic tissue in vivo. RESULTS: Seventeen patients with 24 polyps (13 adenomatous, 11 non-adenomatous) were studied. The autofluorescence decay from adenomas was faster than that from non-adenomas. The measured decay time provided a means of distinguishing adenomas from non-adenomas with a sensitivity of 85%, a specificity of 91%, a positive predictive value of 92%, and a negative predictive value of 83%. CONCLUSIONS: Time-resolved autofluorescence spectroscopy is a promising optical diagnostic technique for determining polyp types in vivo.

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Adenomatous PolypsColonColonic PolypsColonoscopesColonoscopyDiagnosis, DifferentialEquipment DesignFeasibility StudiesHumansLasersSpectrometry, FluorescenceTime FactorsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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M A Mycek, K T Schomacker, N S Nishioka. 1998. Colonic polyp differentiation using time-resolved autofluorescence spectroscopy.. https://doi.org/10.1016/s0016-5107(98)70009-4

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