[Narrow band imaging: new paradigm in gastrointestinal video-endoscopy].

Novel technologies in gastrointestinal endoscopy, such as magnification and high resolution endoscopy, have a clear aim in improving diagnostic accuracy of mucosal abnormalities. Narrow band imaging encompasses both of these by endoscopic display of gastric mucosa with bands of blue and green light. This enhances mucosal architecture and adjacent vasculature. Combined with optical magnification NBI enables recognition of subtle mucosal abnormalities, such as dysplasia in Barrett's oesophagus, early morphological changes of vasculature in inflammatory and malignant diseases of esophagus, stomach and colon. Before NBI becomes a routine diagnostic procedure, further investigations are needed especially in regard to standardisation and validation of findings, as well as their correlation with histopathological findings.