A Feasibility Study of a Modular Video Augmentation System for Image-Guided Skull Base Surgery

Current standard of care for complex head, neck and skull base surgery require navigation systems that allow instruments to be tracked optically or electromagnetically while registered to a patient's pre-operative X-ray computed tomography (CT) or magnetic resonance image (MRI). However, conventionally, the CT/MRI data is not registered with video endoscopy. Augmentation of endoscopic video by preoperative data can facilitate navigation around critical structures and robust target resection. The work presented here describes evaluation of a high definition (HD) video-overlay system for endonasal endoscopic skull base surgery. We adopt a modular design that can be extended for other video augmentation applications. The system supports fast automatic camera calibration, comparable in re-projection errors to standard camera calibration tools, while performing within appropriate run time for clinical use. Phantom studies have shown the registration accuracy of the system to be equivalent to that of conventional optical tracking. With this system we are proposing a clinical pilot study in a small number of patients at Johns Hopkins Hospital to evaluate basic feasibility and to gather qualitative assessment of the video augmentation system.