Narrow-Band Imaging (NBI) selectively uses certain wavelengths of the visible light leading to a shift in the excitation spectrum towards blue light. The first studies with NBI showed that the additional value of NBI in the detection of neoplastic lesions is comparable to chromo-endoscopy, but time saving and easier to perform. The Fujinon Intelligent Chromo-Endoscopy (FICE) system uses a similar theoretical principal as NBI but this is achieved via the use of post hoc computer algorithms, applying different filters to the stored endoscopic images and enabling a theoretically endless number of combinations of filters that can be used. The Pentax I-scan system also allows post hoc modification of the images. On the one hand, surface enhancement enables to better highlight mucosal changes. Spectral modification allows to apply different modes in analogy with to FICE system.