MURAGAKI Yoshihiro    Department   School of Medicine(Tokyo Women's Medical University Hospital), School of Medicine    Position   Visiting Professor
Article types	Original article
Language	Japanese
Peer review	Peer reviewed
Title	Marker-free augmented reality system for image-guided neurosurgery
Domestic / Foregin	Domestic
Volume, Issue, Page	pp.16-22
Authorship	Lead author
Publication date	2012/02
Summary	In image-guided neurosurgery, augmented reality technology is adopted to overlay three-dimensionally reconstructed computer models of a target lesion onto a video image of the surgical field. Optical, electromagnetic, and mechanical tracking systems are usually used for registration between the reconstructed model and a view of the surgical field, but they are both expensive and not without technical problems. In this study, we propose a marker-free registration and tracking method. Initial registration is completed by manually selecting several pairs of anatomically-corresponding points on a reconstructed model and video image. Points are automatically detected (Harris corner detection algorithm) within a predefined region of interest, and a tracking algorithm for machine vision (KLT tracker) is applied for real-time target tracking. A feasibility study using a brain model showed that image overlay was achieved with refresh rate of 8 frames per second. Initial registration error was less than 0.5 mm when more than three pairs of anatomically-corresponding points were selected. This method is feasible and economically advantageous because it does not require an expensive tracking system. In a future study, we will evaluate feasibility and overlaying accuracy in the clinical setting.
NAID	110008802810