Blue Laser Imaging Provides Excellent Endoscopic Images of Upper Gastrointestinal Lesions *

Background/aimImage enhanced endoscopy including narrow band imaging, flexible spectral imaging color enhancement and i-scan is useful for detailed examination of upper gastrointestinal lesions. We aimed to clarify the usefulness of blue laser imaging (BLI) method, a new endoscopic system, to image upper gastrointestinal lesions.ProcedureWe observed upper gastrointestinal lesions including early gastric cancer and early esophageal cancer using white light images and subsequently BLI bright images and BLI images.ResultsIn gastric cancer, irregular microvessels on the tumor surface are clearly identified for both differentiated and undifferentiated lesions with high magnification, similar to those using narrow band imaging. In addition, irregular surface patterns are seen in differentiated lesions by enhanced white circles, which form white zones on the tumor surface. Finding these circles allow us to rule out undifferentiated lesions. Another advantage is to enhance gastric intestinal metaplasia as green-colored mucosa in both distant and close-up views, leading to higher color contrast with brown gastric cancers. This leads to early detection of gastric cancers and shows a demarcation line between the cancer and areas of metaplasia. In squamous cell carcinoma of the esophagus, BLI produces a higher color contrast between brown lesions with intraepithelial papillary capillary loops and the surrounding area without magnification. The extent of Barrett׳s esophagus is easily shown as a high color contrast with the brown gastric mucosa.ConclusionsBlue laser imaging produces excellent images useful for detection and detailed examination of upper gastrointestinal lesions.