Abstract
Recently, magnifying endoscopy (ME) has been applied to the diagnosis of early gastric cancer. In addition, ME with narrow-band imaging (NBI) can visualize various anatomical components. In order to understand the principles behind such techniques, we describe herein the difference between magnifying ratio and resolution, NBI technique and standard endoscopy techniques. Furthermore, we should familiarize ourselves with the microanatomy which can be visualized with NBI-ME, and how this is achieved. As for the microvascular architecture (V), subepithelial capillaries, collecting venules and pathological microvessels are visualized, whereas for the microsurface structure (S), the marginal crypt epithelium and white opaque substance are visualized. We proposed the so-called “VS classification system” for the diagnosis of early gastric caner with NBI-ME. There are several preliminary reports which have described the clinical usefulness of NBI-ME. However, studies investigating the use of NBI-ME for early gastric cancer are limited in number and in quality. More and better-designed studies are needed in order to evaluate the possible indication for NBI-ME and the additional value of NBI over white light imaging.
