Narrow-band imaging system with magnifying endoscopy for superficial esophageal lesions

Background: By assessing the intrapapillary capillary loop in esophageal mucosa, magnifying endoscopy can play an important role in the evaluation of superficial esophageal lesions. A newly developed narrow-band imaging system was applied to magnifying endoscopy in a clinical setting; the benefit of the narrow-band imaging system was evaluated. Methods: Forty-one patients (37 men, 4 women; mean age 63.5 [7.3] years) were enrolled between March 2002 and January 2003 in the study. Endoscopy was performed with a magnifying endoscope, a standard video-endoscopic system, and a narrow-band imaging system. The assessment consisted of 3 phases: a numerical analysis of the red, green, blue color value of endoscopic images, creation of model images, and assessment on the actual images. In the numerical analysis, the red, green, blue color value for intrapapillary capillary loop and background mucosa were obtained, and the ratio and contrast value were calculated. Results: In the numerical analysis, both the ratio and the contrast value between the intrapapillary capillary loop and background mucosa were statistically different. Based on an evaluation of created model images, almost all assessors found the narrow-band imaging system to be superior. In the assessment of actual images, the narrow-band imaging system improved overall accuracy for depth of invasion, especially for inexperienced endoscopists. Conclusions: The narrow-band imaging system improved the accuracy of magnifying endoscopy for assessment of esophageal lesion.