Restoration of lung homeostasis following injury requires efficient wound healing by the epithelium. The mechanisms of lung epithelial wound healing include cell spreading and migration into the wounded area and later cell proliferation. We hypothesized that mechanical properties of cells vary near the wound edge, and this may provide cues to direct cell migration. To investigate this hypothesis, we measured variations in the stiffness of migrating human bronchial epithelial cells (16HBE cells) ∼2 h after applying a scratch wound. We used atomic force microscopy (AFM) in contact mode to measure the cell stiffness in 1.5-μm square regions at different locations relative to the wound edge. In regions far from the wound edge (>2.75 mm), there was substantial variation in the elastic modulus in specific cellular regions, but the median values measured from multiple fields were consistently lower than 5 kPa. At the wound edge, cell stiffness was significantly lower within the first 5 μm but increased significantly between 10 and 15 μm before decreasing again below the median values away from the wound edge. When cells were infected with an adenovirus expressing a dominant negative form of RhoA, cell stiffness was significantly decreased compared with cells infected with a control adenovirus. In addition, expression of dominant negative RhoA abrogated the peak increase in stiffness near the wound edge. These results suggest that cells near the wound edge undergo localized changes in cellular stiffness that may provide signals for cell spreading and migration.

Benign tracheal stenosis can cause dyspnea, wheezing, and cough mimicking other obstructive lung diseases which often leads to a delay in the diagnosis. Risk factors and etiologies for tracheal strictures include autoimmune diseases, infection, gastro-esophageal reflux disease (GERD), radiation injury and iatrogenic factors such as post-intubation and post-tracheostomy. Once suspected, tracheal strictures are diagnosed by performing a thorough evaluation involving clinical exam, laboratory workup, pulmonary function test, chest imaging and bronchoscopy. Bronchoscopy plays a pivotal role in the diagnosis of stenosis and along with the imaging and physiologic assessments leads to a proper description of the stenosis based on all parameters that matters for management. Surgical resection provides a definitive management in most patients with idiopathic or post intubation/tracheostomy stenosis, however, factors such as severe co-morbidities, length and location of the stricture can preclude patients from undergoing curative surgery. Several bronchoscopic interventions including mechanical or laser assisted dilation, electrosurgery (ES), airway stenting and pharmacological treatment with mitomycin C (MMC) and intralesional steroid have been reported in the literature for management of patients who are not surgical candidates. Herein, we review the role of bronchoscopy and illustrate the importance of a multi-disciplinary team (MDT) approach comprising of interventional pulmonologists, thoracic surgeons and otorhinolaryngologists in the diagnosis and management of patients with benign tracheal stenosis.

Recent advances in navigational platforms have led bronchoscopists to make major strides in diagnostic interventions for pulmonary parenchymal lesions. Over the last decade, multiple platforms including electromagnetic navigation and robotic bronchoscopy have allowed bronchoscopists to safely navigate farther into the lung parenchyma with increased stability and accuracy. Limitations persist, even with these newer technologies, in achieving a similar or higher diagnostic yield when compared to the transthoracic computed tomography (CT) guided needle approach. One of the major limitations to this effect is due to CT-to-body divergence. Real-time feedback that better defines the tool–lesion relationship is vital and can be obtained with additional imaging using radial endobronchial ultrasound, C-arm based tomosynthesis, cone-beam CT (fixed or mobile), and O-arm CT. Herein, we describe the role of this adjunct imaging with robotic bronchoscopy for diagnostic purposes, describe potential strategies to counteract the CT-to-body divergence phenomenon, and address the potential role of advanced imaging for lung tumor ablation.

Flexible bronchoscopy plays a critical role in both diagnostic and therapeutic management of a variety of pulmonary disorders in the bronchoscopy suite and the intensive care unit. In the set-ting of the ongoing viral pandemic, single-use flexible bronchoscopes (SUFB) have garnered attention as various professional pulmonary societies have released guidelines regarding uses for SUFB given the concern for risk of viral transmission when using reusable flexible bronchoscopes (RFB). In addition to offering sterility, SUFBs are portable, easily accessible, and may be more cost-effective than RFB when considering the potential costs of treating bronchoscopy-related infections. Furthermore, since SUFBs are one time use, they do not require reprocessing after use, and therefore may translate to reduced cleaning and storage costs. Despite these advantages, RFBs are still routinely used to perform advanced diagnostic and therapeutic bronchoscopic procedures given the need for optimal maneuverability, handling, angle of deflection, image quality, and larger channel size for passing of ancillary instruments. Here, we review the published evidence on the applications of single-use and reusable bronchoscopes in bronchoscopy suites and intensive care units. Specifically, we will discuss the advantages and disadvantages of these devices as pertinent to fundamental, advanced, and therapeutic bronchoscopic interventions.

With recommendations for low dose CT scan for lung cancer screening, there has been an increase in the finding of lung nodules and peripheral pulmonary lesions (PPLs). Additionally, when there is concern for malignancy, guidelines have recommended performing the least invasive evaluation. Conventional bronchoscopy diagnostic yields for PPLs have reportedly been quite low and prior electromagnetic navigation bronchoscopy (ENB) studies have reported variable yields. Navigation bronchoscopy in addition to endobronchial ultrasound allows a physician to evaluate peripheral lung lesions along with mediastinal and hilar lymph nodes for the diagnosis and staging of suspected malignancy in one procedure. More recent advances in navigational bronchoscopy including the use of augmented fluoroscopy (AF), cone beam CT, and robotic bronchoscopy have pushed the boundaries of capability in evaluating PPLs. These added bronchoscopic technologies have shown to improve diagnostic yield especially when modalities are used in combination. The ultimate goal of endoscopically localized ablative and therapeutic treatment for peripheral lung lesions will require a high level of physician confidence, accuracy, and precision. This article will review the innovative characteristics and data of some of the more recently available navigational bronchoscopy devices.