Propagation of Probabilistic Tractography of the Optic Radiation for Neuronavigation in Epilepsy Surgery

Gavin P. Winston¹, Pankaj Daga², Jason Stretton¹, Marc Modat², Mark R. Symms¹, Andrew W. McEvoy³, Sebastien Ourselin², John S. Duncan^1,3

Anterior temporal lobe resection (ATLR) is an effective treatment for temporal lobe epilepsy refractory to medication, but leads to a visual field deficit in between 52% and 100% of patients. Probabilistic tractography is required to accurately depict Meyer's loop of the optic radiation, but cannot be performed in real-time. Propagation of preoperative probabilistic tractography to intraoperative images using non-linear registration techniques accounting for brain shift and deformation and subsequent integration into the neuronavagional suite should improve the outcome from epilepsy surgery. Such a technique is described and validated with outcome in patients undergoing ATLR using pre- and postoperative images.