From Respirology: Frontiers in Bronchoscopic Imaging

http://www.ncbi.nlm.nih.gov/pubmed/22126413

Respirology. 2011 Nov 29. doi: 10.1111/j.1440-1843.2011.02108.x. [Epub ahead of print]
Frontiers in Bronchoscopic Imaging.
Ohtani K, Lee AM, Lam S.
Source
Department of Surgery, Tokyo Medical University, Tokyo, Japan & Visiting Fellow, Cancer Imaging Unit, Integrative Oncology Department, British Columbia Cancer Agency Research Centre, British Columbia, Canada Cancer Imaging Unit, Integrative Oncology Department, British Columbia Cancer Agency Research Centre & the University of British Columbia, British Columbia, Canada.

Abstract
Bronchoscopy is a minimally-invasive method for diagnosis of diseases of the airways and the lung parenchyma. Standard bronchoscopy uses the reflectance/scattering properties of white light from tissue to examine the macroscopic appearance of airways. It does not exploit the full spectrum of the optical properties of bronchial tissues. Advances in optical imaging such as optical coherence tomography (OCT), confocal endomicroscopy, autofluorescence imaging and laser Raman spectroscopy are at the forefront to allow in-vivo high resolution probing of the microscopic structure, biochemical compositions and even molecular alterations in disease states. OCT can visualize cellular and extracellular structures at and below the tissue surface with near histologic resolution as well as to provide three-dimensional imaging of the airways. Cellular and sub-cellular imaging can be achieved using confocal endomicroscopy or endocytoscopy. Contrast associated with light absorption by hemoglobin can be used to highlight changes in microvascular structures in the sub-epithelium using narrow band imaging. Blood vessels in the peribronchial space can be displayed using Doppler OCT. Biochemical compositions can be analyzed with laser Raman spectroscopy, autofluorescence or multi-spectral imaging. Clinically, autofluorescence and narrow band imaging have been found to be useful for localization of pre-neoplastic and neoplastic bronchial lesions. OCT can differentiate carcinoma in-situ versus micro-invasive cancer. Endoscopic optical imaging is a promising technology that can expand the horizon for studying the pathogenesis and progression of airway diseases such as COPD and asthma as well as to evaluate the effect of novel therapy.