Tu1675 Interobserver and Intraobserver Variation in the Diagnosis of Minimal Change Esophagitis by High Definition and I-SCAN Upper Endoscopy

Abstract

Interobserver and Intraobserver Variation in the Diagnosis of Minimal Change Esophagitis by High Definition and I-SCAN Upper Endoscopy Jaksin Sottisuporn*, Nisa Netinatsunton, Naichaya Chamroonkul, Teepawit Witeerungrot, Theeratus Jongboonyanuparp, Siriboon Attasaranya, Bancha Ovartlarnporn NKC institute of Gastroenterology and Hepatology, Hatyai, Thailand Background: Minimal changes esophagitis lesions (MCL) has been regarded as one of the spectrum of erosive esophagitis in some studies. The MCLs are subtle changes and are difficult to identify by conventional endoscopy. I-Scan endoscopy (SE) is a new imaging technology that enhances the mucosal details. Limited studies showed the SE to be better than white light endoscopy in detecting MCL. The intraobserver and interobserver variations of SE in detecting MCL have never been reported before. Aim: To assess the intraand interobserver variations in detecting MCL by high-definition endoscopy (HD) and SE in tone enhancement mode for esophagus (TE-e) in dyspeptic patients. Method: The endoscopic images in HD and TE-e modes of distal esophagus of all patients with upper abdominal symptoms scheduled for upper gastrointestinal endoscopy at the NKC institute from February 2010 till August 2011 were used to assess the consistency of images interpretation by 6 endoscopists. A set of images representing MCL that included punctate erythema (PE), blurred vessels (BV), minute erosion (ME) and triangular lesion with elongated pit (TLE) were used to educate all the endoscopists. 6 endoscopists randomly evaluated the endoscopic images of 89 patients in HD and TE-e mode twice with at least 24 hours interval in between. The intra and inter-observer consistency of images interpretation was analyzed. Result: Intraobserver kappa values (95% CI) for HD group were 0.44(0.24-0.65), 0.44(0.24-0.65), 0.410.2-0.62), 0.59(0.39-0.8), 0.45(0.24-0.65), 0.13(0.00-0.34) and for TE-e SE were 0.35(0.15-0.56), 0.56(0.360.77), 0.97(076-1.00), 0.51(0.31-0.71), 0.44 (0.61-0.27), 0.32(0.11-0.53) respectively. These represent fair to excellent agreement for intraobserver image interpretation in both HD and TE-e. One of the endoscopist had significant improvement in detecting MCL on the second image interpretation (kappa 0.13 versus 0.32 p 0.05). In the interobserver consistency of image interpretation, the pairwise kappa values for HD and TE-e of all 6 endoscopists were rather low (range 0.16-0.3 and 0.05-0.37 respectively). When the evaluations in both groups were analyzed by pairing individual endoscopist into 15 pairs, the kappa values improved with agreement in 7 of 15 pairs without statistical significance. (p 1) Conclusions: The intraobsever agreement for MCL by HD and i-Scan is fair to excellent. The poor interobserver agreement by HD and TE-e for MCL limits the value of the MCL in clinical practice. The SE imaging technology did not improve the interobserver image interpretation consistency.