Pulmonary Medicine

Interventional Bronchoscopy: Navigational Bronchoscopy

General description of procedure, equipment, technique

Navigational Bronchoscopy

Initially defined in 1995 and subsequently described in European Respiratory Society (ERS) and American Thoracic Society (ATS) guidelines, interventional pulmonology is "the art and science of medicine as related to the performance of diagnostic and invasive therapeutic procedures that require additional training and expertise beyond that required in a standard pulmonary medicine training program." Clinical entities encompassed within the discipline include complex airway management, benign and malignant central airway obstruction, pleural diseases, and pulmonary vascular procedures.

Diagnostic and therapeutic procedures pertaining to these areas include rigid bronchoscopy, transbronchial needle aspiration, autofluorescence bronchoscopy, endobronchial ultrasound, transthoracic needle aspiration and biopsy, laser bronchoscopy, endobronchial electrosurgery, argon-plasma coagulation, cryotherapy, airway stent insertion, balloon bronchoplasty and dilatation techniques, endobronchial radiation (brachytherapy), photodynamic therapy, percutaneous dilatational tracheotomy, transtracheal oxygen catheter insertion, medical thoracoscopy, and image-guided thoracic interventions. This presentation focuses on electromagnetic navigational bronchoscopy (ENB).

Navigational bronchoscopy provides a virtual three-dimensional map of the lung, enabling the physician to perform an anatomically precise biopsy, place markers for radiation therapy, and/or facilitate surgical removal of a small peripheral lung lesion or thermal ablative techniques for peripheral lung lesions. Navigational systems use either electromagnetic or computer assistance to identify air columns in the lung to reach the final precise destination.

Indications and patient selection

Navigational bronchoscopy is used to perform biopsy of peripheral lung lesions, place markers for radiation therapy, and/or facilitate surgical removal of a small peripheral lung lesion.

Contraindications

The clinician's inability to perform bronchoscopy safely and the patient's ability to tolerate it safely are contraindications to the procedure.

Details of how the procedure is performed

Multiple commercially available platforms to perform electronavigation bronchoscopy exist with slight variations in both pre-procedural planning and execution of the procedure. We will address the procedural techniques in a general manner.

Several preparatory steps are required prior to performing the bronchoscopy. A thin cut CT scan is performed in order to be able to contruct a 3-dimensional rendering of the airway tree. This allows for the creation of an airway map and delineation of a pathway to the target lesion. The CT images are then transferred to a laptop computer containing specific proprietary software and the procedure is planned, creating a "virtual map" that is placed in the navigational system.

The patient is positioned supine in an electromagnetic field with sensors placed over the chest so as to track bronchoscope via a guide that is advanced through the working channel of the bronchoscope. The bronchoscope is directed towards the target via directions from the virtual map. Once the bronchoscope is advanced as far into airways as possible the guidance probe is advanced without the image guidance of the bronchoscope optic, rather using the detectors from the electromagnetic field. Fluoroscopy or radial endobronchial ultrasound (rEBUS) are often used in combination with electromagnetic guidance technology to confirm the position prior to attempting to sample the target lesion. A variety of steerable catheters can be utilized, and biopsy forceps or brushes may be passed to obtain tissue’ alternatively fiducial markers may be placed or the lung tattooed prior to surgical resection.

Interpretation of results

Not applicable.

Performance characteristics of the procedure (applies only to diagnostic procedures)

Several studies have reported a diagnostic yield of 64% to 69% if the lesion was larger than 2 cm. In a multicenter, randomized, controlled trial that studied three arms - rEBUS, ENB, and rEBUS combined with ENB, the diagnostic yield with EBUS alone was 69% and navigation only was 59%, whereas the combined yield of EBUS with ENB was 88%. This result has not been reproduced elsewhere.

Alternative and/or additional procedures to consider

Several alternatives to ENB exist, including the use of ultrathin bronchoscopes, radial endobronchial ultrasound, and percutaneous approaches including transthoracic needle.

Complications and their management

Common complications of transbronchial biopsy usually performed in association with ENB include pneumothorax and bleeding.

You must be a registered member of Infectious Disease Advisor to post a comment.

Sign Up for Free e-newsletters