Optical coherence tomography and confocal laser endomicroscopy in pulmonary diseases

Purpose of review Current imaging techniques (X-ray, computed tomography scan, ultrasound) have limitations in the identification and quantification of pulmonary diseases, in particular, on highly detailed level. The purpose of this review is to provide an overview of the current knowledge of innovative light-and laser-based imaging techniques that might fill this gap. Recent findings Optical coherence tomography (OCT) and confocal laser endomicroscopy (CLE) are high-resolution imaging techniques, which, combined with bronchoscopy, provide 'near histology' detailed imaging of the airway wall, lung parenchyma, mediastinal lymph nodes, and pulmonary vasculature. This article reviews the technical background of OCT and CLE, summarizes study results, and discusses its potential clinical applications for various pulmonary diseases. Summary Although investigational at the moment, OCT and CLE are promising innovative high-resolution optical imaging techniques for the airway wall, lung parenchyma, mediastinal lymph nodes, and pulmonary vasculature. Clinical applications might contribute to improved disease identification and quantification, guidance for interventions/biopsies, and patient selection for treatments. Development of validated identification and quantification image-analysis systems is key for the future application of these imaging techniques in pulmonary medicine.