Feasibility Study of Removable Fiducial Marker Implantation with the Intelligent Navigation Bronchoscopy Technology in Robotic Radiosurgery System Tracking

Abstract

<h3>Purpose/Objective(s)</h3> To investigate the feasibility of removable fiducial marker implantation with the intelligent navigation bronchoscopy technology in a frameless robotic radiosurgery system tracking. <h3>Materials/Methods</h3> CT scans of an inflatable anti-corruption pig lung were acquired, and two simulated tumor lesion sites were designed in the left and right lung lobes by intelligent navigation software, respectively. According to the principle of fiducial marker implantation, 24 removable fiducial markers were implanted around each simulated tumor lesion via bronchus after intelligent guiding. Simulating the end-expiratory state, the pig lung was scanned again to obtain CT images of the implanted removable fiducial markers and the number of successfully implanted fiducial markers was recorded. Six deliverable treatment plans were designed using the planning system, and then the pig lung plans were delivered based on the simulated respiratory movements. After the treatment, the implanted removable fiducial markers were retrieved through bronchoscopy, and the number of successful retrievals was recorded. The rigid body error and translation error were extracted and analyzed from the log file. <h3>Results</h3> No removed fiducial markers slipped and fell off during the experiment. 24 removable fiducial markers were successfully implanted under bronchoscopic intelligent magnetic navigation guidance, with a 100% implantation success rate (24/24) and 100% removable success rate (24/24). The fiducial marker tracking rate was 83.33% (20/24), with 4 fiducial markers being too far away from the simulated tumor location to be used during the tracking process. The data from the log file displayed that the mean rigid body error for 6 groups was 1.45 mm, the mean translation error was 1.78 mm. <h3>Conclusion</h3> The technology of bronchoscopy intelligent navigation and implantation of removable fiducial marker is feasible, and the tracking accuracy of the frameless robotic radiosurgery system can meet the clinical requirements, which has a good clinical application and teaching application prospect.