When examining tissue masses or tumors inside the lungs, a standard flexible bronchoscope is typically used. However, many bronchoscopes cannot find or reach tumors located in the periphery of the lungs, where smaller bronchi are not wide enough to permit passage of a normal scope.
Over two-thirds of lung masses are located in the periphery of the lungs. Navigational bronchoscopy is a technology which combines electromagnetic navigation with real-time 3D CT images, enabling doctors to biopsy and treat masses in these distant regions of the lungs.
Before undergoing a navigational bronchoscopy procedure, a CT scan is performed to locate potential tumors in the lung. The CT scan is then loaded onto a computer and used to create a virtual, three-dimensional "roadmap" of the lung. A doctor marks where the target lesions are located on the virtual map and plans how to navigate through the lung to reach the lesions.
For the procedure, the patient lies on a low-frequency electromagnetic bed. A bronchoscope, containing an extended working channel (EWC) and locatable guide, is inserted into the patient’s airway, down the trachea and into the bronchi. The electromagnetic bed allows the doctor to view the locatable guide in real-time on the virtual map to carefully guide the scope deep into the lung. The doctor is able to control the movement and direction of the locatable guide as it travels into the smallest bronchiole. Once a target lesion is reached, the locatable guide is removed and a surgical instrument is passed through the EWC to collect a biopsy for testing.
Navigational bronchoscopy may also be used in conjunction with external beam radiation therapy, such as TomoTherapy, to treat peripheral tumors with a precise form of radiation that delivers a high dose to the tumor while reducing radiation exposure to surrounding healthy tissue.