Narrow-Band Imaging (NBI) is developed by Olympus inc. and selectively uses certain wavelengths of the visible light leading to a shift in the excitation spectrum towards blue light. The intensity of the blue bandwidth is also enhanced. This leads to a more superficial penetration of the emitted light into the mucosa of the intestine and enhancement of more superficial structures (e.g. irregularities, small flat lesions or polyps) and small superficial mucosal vessels (indicative of neoplasia).