Navigational bronchoscopy seeks to overcome the challenges of conventional bronchoscopy, which is limited by the size and flexibility of the scope. Navigational bronchoscopy can be used during peripheral nodule biopsy for small, difficult-to-reach lung nodules that are typically not accessible using conventional bronchoscopy. 

Between the windpipe and alveoli, the airways branch 17 to 24 times. Most bronchoscopes can only reach 4 or 5 of these airway divides because of the diameter of the remaining airways and limited flexibility of the scope. This results in conventional bronchoscopy being limited to the outer one-third of the lung and it carries a diagnostic accuracy of 31%.

 Diagnostic accuracy has increased with the application of updated ultrasound technology, such as radial endobronchial ultrasound and early navigational systems, reaching the 50% level in larger health care centers.

 As these ranges were still considered unacceptably low, a push for further advancements, including robotic bronchoscopy, has enhanced the diagnostic yield.

Navigational bronchoscopy can be thought of as a global positioning system (GPS) for the bronchoscopist. Similar to a GPS device leading a driver to a distant, unfamiliar city via state highways, then down district roads and eventually city streets, a navigational bronchoscope uses a weak electromagnetic field to triangulate the positions of chest sensors, a field generator, and the scope tip to determine the biopsy location and help drive the scope to the target. Navigational bronchoscopy can be combined with virtual bronchoscopy by running a high-resolution CT scan through imaging software to “map out” the airway.

The power of robotic navigational bronchoscopy ensures increased reach, stability, and vision. The robotic scopes on the market have been demonstrated to extend an average of 4 airway branch points farther than existing ultrathin scopes.

 This is because of cables throughout the length of the scope that are capable of articulation, in contrast to conventional scopes which can only articulate within the last 5 cm of the scope. This articulation can be locked into place, such that a bronchoscopist can step back from the table and review slides or discuss findings without fear of the scope changing position.

The ability to lock a scope in place is a tremendous improvement over existing technologies, which can lose position during instrument insertion or as the plastic parts warmed to body temperature. Further, with the Monarch platform, for example, maintenance of scope vision out to the periphery of the lung enables the visualization of peripheral tumors before biopsy. It is therefore no surprise that the diagnostic accuracy of such procedures jumped to the mid-80% range when using navigational bronchoscopy.

Who Needs Robotic Navigational Bronchoscopy?

We have an “epidemic” of lung nodules in the United States, with a tremendous number found each year. Between 2006 and 2012, before lung cancer screening was widely adopted, more than 1.5 million lung nodules were identified in Americans undergoing CT scans.

Any patient with a suspicious pulmonary nodule is a candidate for robotic bronchoscopy, with the final determination dependent on the level of suspicion of lung cancer, size of the nodule, and proximity to the edge of the lung. Although robotic bronchoscopy has a slightly lower diagnostic yield than a CT-guided biopsy, it has the advantage of a slightly lower complication rate and the ability to stage the mediastinum in the same procedure.

What Is the Future of Robotic Navigational Bronchoscopy?

What new robotic navigational bronchoscopy technologies are on the horizon? I very much look forward to new systems that will enhance both diagnostic yield and treatment effectiveness. Using a robotic navigational bronchoscope and cone-beam CT, which provides a more accurate cross-sectional image directly before biopsy, interventional pulmonologists are demonstrating diagnostic yields that will rival those of CT-guided biopsies.

Treatments that may be considered for peripheral nodules include microwave ablation, photodynamic therapy, or direct injection of chemotherapeutics into the nodules. These treatments could be combined with other modalities, including surgery or radiation, to advance the field and improve lung cancer survival.

Baaklini WA, Reinoso MS, Gorin AB, Sharafkaneh A, Manian P. Diagnostic yield of fiberoptic bronchoscopy in evaluating solitary pulmonary nodules. 

. 2000;117(4):1049-1054. doi:10.1378/chest.117.4.1049

Ost DE, Ernst A, Lei X, et al; AQuIRE Bronchoscopy Registry. Diagnos-tic yield and complications of bronchoscopy for peripheral lung lesions. Results of the AQuIRE Registry. 

. 2016;193(1):68-77. doi:10.1164/rccm.201507-1332OC

Chen AC, Gillespie CT. Robotic endoscopic airway challenge: REACH assessment. 

. 2018;106(1):293-297. doi:10.1016/j.athoracsur.2018.01.051

Wagh A, Ho E, Murgu S, Hogarth DK. Improving diagnostic yield of navigational bronchoscopy for peripheral pulmonary lesions: a review of advancing technology. 

. 2020;12(12):7683-7690. doi:10.21037/jtd-2020-abpd-003

Gould MK, Tang T, Liu ILA, et al. Recent trends in the identifica-tion of incidental pulmonary nodules. 

. 2015;192(10):1208-1214. doi:10.1164/rccm.201505-0990OC

Benn BS, Romero AO, Lum M, Krishna G. Robotic-assisted navigation bronchoscopy as a paradigm shift in peripheral lung access. 

. 2021;199(2):177-186. doi:10.1007/s00408-021-00421-1

Articles

Nathaniel Ivanick, MD, FCCP, explains advancements in the use of robotic navigational bronchoscopy for the diagnosis of early-stage lung cancer.

Robotic Navigational Bronchoscopy Advances Diagnosis of Early-Stage   Lung Cancer

Nathaniel Ivanick, MD, FCCP, assistant professor of oncology, thoracic surgeon, Roswell Park Comprehensive Cancer Center, discusses the role of interventional pulmonologists in advanced diagnostics in lung cancer.

Interventional pulmonologists serve 2 main roles in the management of lung cancer: advanced diagnostics and therapeutics, Ivanick explains. Advanced diagnostics are done for patients with early- and late-stage disease. 

Advanced diagnostics may include obtaining biopsies of small peripheral lung nodules that were historically inaccessible by robotic navigational scopes, Ivanick says. These technological advances allow for earlier-stage disease to be diagnosed when patients are eligible for surgery. 

In cases of lung cancer that have spread to the hilar and mediastinal lymph nodes, linear endobronchial ultrasound (EBUS) can identify lymph nodes near the surface of the airway to be biopsied, Ivanick explains. Linear EBUS represents a significant advancement as this was previously accomplished by mediastinoscopy or CT-guided lymph node biopsies. With linear EBUS, malignancies in lymph nodes as small as 5 mm can be identified, Ivanick adds. 

Finally, in patients with pleural disease, interventional pulmonology can identify malignancies within the pleura and match patients to optimal treatments, Ivanick concludes.

Videos

Nathaniel Ivanick, MD, FCCP, discusses the role of interventional pulmonologists in advanced diagnostics in lung cancer.  



Dr. Ivanick on the Diagnostic Role of Interventional Pulmonologists in Lung Cancer 

Nathaniel Ivanick, MD, FCCP, assistant professor of oncology, thoracic surgeon, Roswell Park Comprehensive Cancer Center, discusses advancements in interventional pulmonology.

In the past several years, the field of interventional pulmonology has witnessed significant growth, Ivanick explains. Diagnostically, the development started with the integration of conventional bronchoscopy, which allowed for further examination of lesions. This was followed by radial endobronchial ultrasound-guided transbronchial cryobiopsy wherein the centers of peripheral lesions could be assessed, greatly increasing diagnostic accuracy for patients, Ivanick says.

Following these advancements was the integration of navigational bronchoscopy and robotic navigational bronchoscopy. These technologies allowed providers to adequately biopsy lesions that were previously too small or in peripheral areas to be tested, Ivanick says. 

In addition to diagnostic advances, therapeutic development with microwave ablation and photodynamic therapy could emerge into mainstream clinical practice within the next 5 years, Ivanick concludes.

Nathaniel Ivanick, MD, FCCP, discusses advancements in interventional pulmonology.

Nathaniel Ivanick, MD, FCCP

Articles

Robotic Navigational Bronchoscopy Advances Diagnosis of Early-Stage Lung Cancer

Dr. Ivanick on the Diagnostic Role of Interventional Pulmonologists in Lung Cancer

Dr. Ivanick on Advances in Interventional Pulmonology