Advances in diagnostic bronchoscopy

Abstract

Diagnostic bronchoscopy has undergone two major paradigm shifts in the last 40 years. First, the advent of flexible bronchoscopy gave chest physicians improved access to the tracheobronchial tree with a rapid learning curve and greater patient comfort compared with rigid bronchoscopy. The second paradigm shift has evolved over the last 5 years with the proliferation of new technologies that have significantly enhanced the diagnostic capabilities of flexible bronchoscopy compared with traditional methods. At the forefront of these new technologies is endobronchial ultrasound. In its various forms, endobronchial ultrasound has improved diagnostic yield for pulmonary masses, nodules, intrathoracic adenopathy, and disease extent, thereby reducing the need for more invasive surgical interventions. Various navigational bronchoscopy systems have become available to increase flexible bronchoscope access to small peripheral pulmonary lesions. Furthermore, various modalities of airway assessment, including optical microscopic imaging technologies, may play significant roles in the diagnosis of a variety of pulmonary diseases in the future. Finally, the combination of new diagnostic bronchoscopy technologies and novel approaches in molecular analysis and biomarker assessment hold promise for enhanced diagnosis and personalized management of many pulmonary disorders. In this review, we provide a contemporary review of diagnostic bronchoscopy developments over the past decade.

Figure 1.

Two forms of endobronchial ultrasound (EBUS). (A) The ultra-miniature (UM)-EBUS contains a circulating ultrasound crystal that provides a 360° view of the surrounding structures when full airway ultrasonographic coupling occurs. This probe is inserted through a guide sheath (arrow; Olympus Corporation, Tokyo, Japan), which can be left behind in the airway on UM-EBUS probe removal to direct instruments for biopsy. (B) This UM-EBUS image demonstrates a focal lesion (asterisk) surrounding the probe. (C) The convex probe (CP)-EBUS TBNA (BF-UC160F-OL8; Olympus Corporation, Tokyo, Japan) videobronchoscope has an integrated ultrasound probe that scans 90° perpendicular from the longitudinal axis, a 35° forward oblique video view, and a 2.0-mm working channel through which a dedicated biopsy needle can be passed. Distal tip dimples on the needle provide an echogenic surface to reflect ultrasound waves to allow needle visualization. (D) This CP-EBUS image demonstrates a left paratracheal lymph node with the ascending aorta (Ao), the pulmonary artery (PA), and the needle present in the lymph node.

Figure 2.

Vascular lesions detected by convex probe endobronchial ultrasound (CP EBUS). (A) A 56-year-old man with progressive dyspnea and a CT scan demonstrating mediastinal adenopathy and proximal pulmonary artery filling defects interpreted as pulmonary embolism. CP EBUS–TBNA was performed of the mediastinal lymph nodes and scanning of the vasculature demonstrated the intraluminal filling defects with cystic structures (arrow). TBNA demonstrated only blood and the patient underwent catheter-directed endovascular biopsy, which confirmed high-grade angiosarcoma. (B) A 65-year-old smoking woman (75 pack-years) presented with cough and dyspnea and was found to have a right hilar mass with mediastinal adenopathy. Mediastinal node CP EBUS-TBNA confirmed adenocarcinoma, but scanning lower into the right hilar area demonstrated tumor vascular invasion into the right pulmonary artery inferior branch.

Figure 3.

Flexible confocal fibered microscopy. (A) Schematic representation of fibered confocal fluorescence microscopy, whereby laser light excites biologic tissue generating autofluorescence, which is detected to generate an image (Cellvizio; Mauna Kea Technologies, Paris, France). (B) Normal alveolar architecture demonstrating alveolar septa (arrowhead) with a few scattered alveolar macrophages (arrow). (C) Emphysematous lung with loss of many alveolar septa and large alveolar spaces. (D) Fairly well-preserved alveolar architecture, but with increased alveolar macrophage number.