Combining autofluorescence imaging and narrow-band imaging for the differentiation of adenomas from non-neoplastic colonic polyps among experienced and non-experienced endoscopists.
OBJECTIVE
Endoscopic tri-modal imaging incorporates high-resolution white-light endoscopy (HR-WLE), narrow-band imaging (NBI), and autofluorescence imaging (AFI). Combining these advanced techniques may improve endoscopic differentiation between adenomas and non-neoplastic polyps. In this study, we aimed to assess the interobserver variability and accuracy of HR-WLE, NBI, and AFI for polyp differentiation and to evaluate the combined use of AFI and NBI.


METHODS
First, still images of 50 polyps (22 adenomas; median 3 mm) were randomly displayed to three experienced and four non-experienced endoscopists. All HR-WLE and NBI images were scored for Kudo classification and AFI images for color. Second, the combined AFI and NBI images were assessed using a newly developed algorithm by six additional non-experienced endoscopists.


RESULTS
The outcomes measured were interobserver agreement and diagnostic accuracy using histopathology as reference standard. Experienced endoscopists had better interobserver agreement for NBI (kappa=0.77) than for AFI (kappa=0.33), whereas non-experienced endoscopists had better agreement for AFI (kappa=0.58) than for NBI (kappa=0.33). The accuracies of HR-WLE, NBI, and AFI among experienced endoscopists were 65, 70, and 74, respectively. Figures among non-experienced endoscopists were 57, 63, and 77. The algorithm was associated with a significantly higher accuracy of 85% among all observers (P<0.023). These figures were confirmed in the second evaluation study.


CONCLUSIONS
Non-experienced endoscopists have better interobserver agreement and accuracy for AFI than for HR-WLE or NBI, indicating that AFI is easier to use for polyp differentiation in non-experienced setting. The newly developed algorithm, combining information of AFI and NBI together, had the highest accuracy and obtained equal results between experienced and non-experienced endoscopists.
van den Broek
Frank J C
FJ
Department of Gastroenterology and Hepatology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
van Soest
Ellert J
EJ
Naber
Anton H
AH
van Oijen
Arnoud H A M
AH
Mallant-Hent
Rosalie Ch
RCh
Böhmer
Clarisse J M
CJ
Scholten
Pieter
P
Stokkers
Pieter C F
PC
Marsman
Willem A
WA
Mathus-Vliegen
Elisabeth M H
EM
Curvers
Wouter L
WL
Bergman
Jacques J G H M
JJ
van Eeden
Susanne
S
Hardwick
James C H
JC
Fockens
Paul
P
Reitsma
Johannes B
JB
Dekker
Evelien
E
D000236:Adenoma / Q000473:pathology*; D000465:Algorithms; D002983:Clinical Competence; D003110:Colonic Neoplasms / Q000473:pathology*; D003111:Colonic Polyps / Q000473:pathology*; D003113:Colonoscopy / Q000379:methods*; D003937:Diagnosis, Differential; D005260:Female; D005453:Fluorescence; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D015203:Reproducibility of Results