🤖 AI Summary
This study addresses the limitations of conventional neuronavigation systems, which rely on physical fiducials and suffer from cumbersome registration procedures, intraoperative displacement, and patient discomfort. To overcome these challenges, the authors propose a high-precision, markerless neuronavigation method that, for the first time, integrates data from low-cost visible-light and infrared stereo depth cameras. By combining facial geometric modeling with a multimodal sensor fusion algorithm, the approach enables fully automatic and highly robust head registration. In experiments involving 50 subjects, the optimal algorithm achieved a median spatial error of 2.32 mm and an angular error of 2.01°, meeting the clinical accuracy requirements for transcranial magnetic stimulation. This performance significantly surpasses existing markerless techniques while simultaneously reducing system cost and enhancing patient comfort.
📝 Abstract
Neuronavigation is widely used in biomedical research and interventions to guide the precise placement of instruments around the head to support procedures such as transcranial magnetic stimulation. Traditional systems, however, rely on subject-mounted markers that require manual registration, may shift during procedures, and can cause discomfort. We introduce and evaluate markerless approaches that replace expensive hardware and physical markers with low-cost visible and infrared light cameras incorporating stereo and depth sensing combined with algorithmic modeling of the facial geometry. Validation with $50$ human subjects yielded a median tracking discrepancy of only $2.32$ mm and $2.01{\deg}$ for the best markerless algorithms compared to a conventional marker-based system, which indicates sufficient accuracy for transcranial magnetic stimulation and a substantial improvement over prior markerless results. The results suggest that integration of the data from the various camera sensors can improve the overall accuracy further. The proposed markerless neuronavigation methods can reduce setup cost and complexity, improve patient comfort, and expand access to neuronavigation in clinical and research settings.