Bronchoscopic procedure planning for systematic lymph node analysis

Lung cancer is the number one cause of cancer in the United States. With the rollout of new lung cancer screening programs, the number of early-stage lung cancer patients is expected to increase. This greatly increases the premium on proper central-chest lymph node staging. Physicians typically use minimally invasive bronchoscopy for these staging procedures. On another front, it is now accepted practice that a bronchoscopic procedure is greatly assisted using image-guided virtual-bronchoscopy navigation (VBN) systems, whereby the procedure plan and follow-on live guidance draw upon information derived from a patient's three-dimensional (3D) computed-tomography (CT) chest scan. To date, VBN systems only provide a means for managing individual diagnostic sites. Truly effective lymph node staging, however, demands procedure plans that take into account multiple nodes. To bridge this gap, we propose an approach for planning a more comprehensive lymph node staging plan, suitable for VBN-based guidance systems. In addition, during the live guided procedure, existing VBN systems do not provide visualization AIDS pertinent to the demands of the lymph node staging problem. We discuss our progress toward developing a computer-based planning and guidance system tailored to more comprehensive lymph node staging. In particular, our development features three interconnected contributions. First, a system modernized to the newest eighth edition of the IASLC nodal-station map is presented. Second, a method for locating station-specific 3D soft-tissue regions, where candidate lymph nodes could reside, is discussed. Finally, an approach for computing airway routes leading to each nodal station, along with associated visualization views is given. We demonstrate our methodology using data from human lung cancer patients.