Narrow Wave Imaging and Autofluorescence Imaging

Narrow Wave Imaging (NBI) is an optical image emphasizing technique, which is an optical technique originated by Olympus, to emphasize subtle changes in blood vessels and mucosal surfaces. Because the mucous membrane of the inner wall of the digestive tract is rich in blood vessels and hemosiderin, which has a strong ability to absorb narrow-wave light, blood vessel morphology and mucous membrane structure are clearly shown through the contrast between the strong absorption of hemosiderin and the strong reflection of the mucous membrane surface. The blood vessels on the surface of the mucosa are shown in brown color, and the blood vessels in the submucosa are shown in cyan color. In normal observation, the endoscopic light source emits broad-wave light, which shows the natural color of the mucosa. However, the use of broad-wave light is not effective in emphasizing the subtle changes in the superficial mucosal vessels or mucosal tissue patterns (i.e., pit patterns). In order to enhance the contrast and improve the detection rate, NBI has specifically adopted narrow-wave light that conforms to the spectral characteristics of mucosal tissues and hematoxylin. This greatly improves the contrast performance of the image. And combined with excellent visualization, it greatly contributes to accurate diagnosis. Autofluorescence Imaging (AFI), Olympus EVIS LUCERA SPECTRUM's AFI system is equipped with a highly sensitive CCD that accurately captures subtle changes in the mucosa under fluorescence, revealing lesions that are easily missed under routine observation. Blue light produces strong fluorescence when it hits the submucosal layer. If the fluorescence encounters an abnormally developed lesion (e.g., abnormal aggregation of superficial blood vessels or thickening of the mucosa), the light decreases and the fluorescence is dimmed. the AFI function converts these subtle changes into color information, and under fluorescence, the subtle differences between normal mucosa and lesions are emphasized. Normal tissue appears in a greenish hue, while areas with diminished fluorescence appear in a purplish-red color.