Detailed Examination for Tracheobronchial Tree using Narrow Band Imaging

Abstract

Narrow band imaging is a novel system that can be used to observe microvessel structure using a new narrow banding filter instead of the conventional RGB broadband filter. Wavelength ranges of the new NBI filter were 400-430 nm (Blue), 400-430 nm (Green), and 520-560 nm (Red). The main chromophore in bronchial tissues in the visible wavelength range is haemoglobin, which has a maximum absorptive wavelength near 415 nm, and is within the wavelength range for NBI-Blue and Green (400-430 nm). Increased vessel growth and complex networks of tortuous vessels in squamous dysplasia, some dotted vessels in addition to microvessels, vascular networks of various grades in angiogenic squamous dysplasia and several dotted vessels and spiral type vessels of various sizes and various grades in squamous cell carcinoma were clearly observed in NBI with high resolution bronchovideoscopy. This may enable detect the onset of angiogenesis during multi-step carcinogenesis of the lung.