Automatic Transfer of Pre-Operation fMRI Markers into Intra-Operation MR-Images for Updating Functional Neuronavigation

Functional magnetic resonance tomography (fMRI) is used to identify eloquent areas of the brain. In combination with a 3-D anatomical MR dataset this leads to a functional neuronavigation system. During the operation brain shifts result in an increasing inaccuracy. To preserve the advantages of functional neuronavigation for the surgeon, it is necessary to save the functional information. Since fMRI cannot be repeated with unconscious patients this task has to be fulfilled by means of image processing and pattern recognition algorithms. In this paper we present an automatic approach for transfering preoperative markers into an intraoperative 3-D dataset. In the first step the brains are segmented in both image sets which are then registered and aligned. Next, corresponding points are determined. These points are then used to determine the position of the markers by estimating the local influence of brain shift.