Tynan Reid Stevens1, Ryan CN D'Arcy1, Steven D. Beyea1, David B. Clarke2
1IBD-Atlantic, NRC, Halifax, Nova Scotia, Canada; 2QEII Health Science Centre, Halifax, Nova Scotia, Canada
Localization of cortical stimulation (CS) measurements on MR images is subject to error from brain shift at time of dural opening. We present a method for using digitized CS points and a cortical surface mask extracted from a high-resolution MRI to compute first order corrections for brain shift. CS measurements were recorded for nine brain tumor patients using a neuronavigation system. An iterative-closest-point algorithm was developed to minimize the distance between the CS points and the MR-extracted cortical surface. The mean distance between the CS points and brain surface was reduced from 3.8 +/- 0.5 to 1.6 +/- 0.3 mm.