Narrowed-Spectrum Technologies in Endoscopic Imaging of the Upper Gastrointestinal Tract

ABSTRACT Narrowed-spectrum imaging (NSI) technologies, also known as digital or virtual chromoendoscopy, use optical or digital filters to modify the visible light spectrum and thereby enhance mucosal surface and vascular features. Following the introduction of narrow band imaging over a decade ago, NSI technologies have progressed in image resolution and brightness and are now an intricate part of modern diagnostic endoscopy. This review highlights the application of NSI for the diagnosis and characterization of a wide range of upper gastrointestinal disorders with an emphasis on the diagnostic performance of validated classification systems.