Simulation of Corticospinal tract displacement in patients with brain Tumors

Abstract

The spatial relationship between the corticospinal tracts and a brain tumor is important for planning the surgical strategy. Although the white matter tracts can be manually outlined from structural MRI this is time consuming and impractical. To enhance the spatial understanding of the distorted pathology we have established a method to retrieve this structural information automatically by registration of a standardized normal brain atlas to the individual pathologic anatomy of brain tumor patients. The skin and the brain were segmented in the patient MRI volume. Subsequently a deformable volumetric atlas of a single normal subject was registered to the patient brain using affine and non-linear registration techniques. The estimated spatial correspondence between atlas and patient brain was used to warp the corticospinal tracts from the atlas onto the patient. The accuracy of the method was evaluated in 5 patients with extrinsic tumors of different histopathology and location by comparing selected anatomical landmark structures from the projected atlas to their manually segmented counterpart in the patient. Our method enables the visualization of complex anatomical information with minimal user interaction for routine surgical planning that would otherwise demand the acquisition of additional imaging modalities.