The learning curve, accuracy, and interobserver agreement of endoscope-based confocal laser endomicroscopy for the differentiation of colorectal lesions.

BACKGROUND The endoscope-based confocal laser endomicroscopy (eCLE) system allows in vivo imaging of colorectal epithelium. Little is known about the learning curve for accurate interpretation of confocal images acquired with eCLE. OBJECTIVE To determine the learning curve of eCLE, its diagnostic accuracy, and the intra- and interobserver agreement for the differentiation of colorectal lesions. DESIGN Post hoc assessment of selected eCLE images. SETTING Academic centers. PATIENTS This study involved colonoscopic images from 47 patients. MAIN OUTCOME MEASUREMENTS Learning curve of eCLE, accuracy, and intraobserver and interobserver agreement. METHODS Three endoscopists received a short introduction to eCLE before evaluating 90 images. Observers assessed all eCLE images by using the Mainz classification. After each set of 30 images, the accuracy of each observer was assessed. The same procedure was repeated 6 months later by using the same set of images. LIMITATIONS Post hoc assessment. RESULTS There were no significant changes between the first set of 30 images and the 2 consecutive sets (P = .08 and P = .180, respectively). The overall accuracy was 85.6%, 95.6%, and 92.2% for each observer. The κ values of the intraobserver agreement were 0.68, 0.84, and 0.77 for each observer. The κ value for interobserver agreement was 0.73 during the first and 0.72 during the second assessment. CONCLUSIONS Accurate post hoc interpretation of eCLE confocal images can be learned quickly. High diagnostic accuracy was achieved by all 3 observers during the initial stage of the assessment, which remained high thereafter. Intra- and interobserver agreement was substantial for all 3 observers. Future studies should focus on the real-time assessment of eCLE images.

[1]  A. Axon,et al.  Interobserver Variation and Standardized Training for Confocal Laser Endomicroscopy Image Interpretation in the Upper and Lower GI Tract , 2007 .

[2]  A. Polglase,et al.  A fluorescence confocal endomicroscope for in vivo microscopy of the upper- and the lower-GI tract. , 2005, Gastrointestinal endoscopy.

[3]  S. Anandasabapathy.  Endoscopic imaging: emerging optical techniques for the detection of colorectal neoplasia , 2008, Current opinion in gastroenterology.

[4]  Simon K Lo,et al.  The learning curve of in vivo probe-based confocal laser endomicroscopy for prediction of colorectal neoplasia. , 2009, Gastrointestinal endoscopy.

[5]  Noriko Suzuki,et al.  Optical diagnosis of small colorectal polyps at routine colonoscopy (Detect InSpect ChAracterise Resect and Discard; DISCARD trial): a prospective cohort study. , 2009, The Lancet. Oncology.

[6]  David Moher,et al.  Towards complete and accurate reporting of studies of diagnostic accuracy: the STARD initiative. Standards for Reporting of Diagnostic Accuracy. , 2003, Clinical chemistry.

[7]  D. Heresbach,et al.  Miss rate for colorectal neoplastic polyps: a prospective multicenter study of back-to-back video colonoscopies , 2008, Endoscopy.

[8]  Walter Park,et al.  Prevalence of nonpolypoid (flat and depressed) colorectal neoplasms in asymptomatic and symptomatic adults. , 2008, JAMA.

[9]  Alexander Meining,et al.  In vivo histopathology for detection of gastrointestinal neoplasia with a portable, confocal miniprobe: an examiner blinded analysis. , 2007, Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association.

[10]  S. Cross,et al.  In vivo real‐time confocal laser scanning endomicroscopic colonoscopy for the detection and characterization of colorectal neoplasia , 2008, The British journal of surgery.

[11]  A. Polglase,et al.  Pentax confocal endomicroscope: a novel imaging device for in vivo histology of the upper and lower gastrointestinal tract , 2006, Expert review of medical devices.

[12]  Rinku Sutradhar,et al.  Bleeding and perforation after outpatient colonoscopy and their risk factors in usual clinical practice. , 2008, Gastroenterology.

[13]  M. Wallace,et al.  Interobserver agreement and accuracy among international experts with probe-based confocal laser endomicroscopy in predicting colorectal neoplasia. , 2010, Endoscopy.

[14]  Jacob Cohen.  A Coefficient of Agreement for Nominal Scales , 1960 .

[15]  E. Dekker,et al.  Review article: new developments in colonic imaging , 2007, Alimentary pharmacology & therapeutics.

[16]  J. Richard Landis,et al.  Large sample variance of kappa in the case of different sets of raters. , 1979 .

[17]  E. Dekker,et al.  Pilot study of probe-based confocal laser endomicroscopy during colonoscopic surveillance of patients with longstanding ulcerative colitis. , 2011, Endoscopy.

[18]  A. Polglase,et al.  Confocal laser endoscopy for diagnosing intraepithelial neoplasias and colorectal cancer in vivo. , 2004, Gastroenterology.

[19]  Silvia Sanduleanu,et al.  In vivo diagnosis and classification of colorectal neoplasia by chromoendoscopy-guided confocal laser endomicroscopy. , 2010, Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association.

[20]  Michael B. Wallace,et al.  Comparison of probe-based confocal laser endomicroscopy with virtual chromoendoscopy for classification of colon polyps. , 2010, Gastroenterology.

[21]  C. Lightdale,et al.  The safety of intravenous fluorescein for confocal laser endomicroscopy in the gastrointestinal tract , 2010, Alimentary pharmacology & therapeutics.

[22]  Douglas K Rex,et al.  Narrow-band imaging without optical magnification for histologic analysis of colorectal polyps. , 2009, Gastroenterology.

[23]  M F Dixon,et al.  The Vienna classification of gastrointestinal epithelial neoplasia , 2000, Gut.

[24]  J. R. Landis,et al.  The measurement of observer agreement for categorical data. , 1977, Biometrics.