Model-based brain shift compensation in image-guided neurosurgery

Abstract

Intraoperative brain shift compensation is important for improving the accuracy of neuronavigational systems and ultimately, the accuracy of brain tumor resection as well as patient quality of life. Biomechanical models are practical methods for brain shift compensation in the operating room (OR). These methods assimilate incomplete deformation data on the brain acquired from intraoperative imaging techniques (e.g., ultrasound and stereovision), and simulate whole-brain deformation under loading and boundary conditions in the OR. Preoperative images of the patient's head (e.g., preoperative magnetic resonance images (pMR)) are then deformed accordingly based on the computed displacement field to generate updated visualizations for subsequent surgical guidance. Apparently, the clinical feasibility of the technique depends on the efficiency as well as the accuracy of the computational scheme. In this paper, we identify the major steps involved in biomechanical simulation of whole-brain deformation and demonstrate the efficiency and accuracy of each step. We show that a combined computational cost of 5 minutes with an accuracy of 1-2 millimeter can be achieved which suggests that the technique is feasible for routine application in the OR.