BrainX: a virtual reality tool for neurosurgical intervention in epilepsy

Purpose Localizing functional regions of the cortex and deep-brain areas in epileptic patients is an important pre-surgical procedure prior to resection. This is often achieved using intra-cortical electrodes for both stimulation as well as recordings of Local Field Potentials (LFPs), concurrent to behavioral tasks related to language or motor function. To assist and improve accuracy in the identification of relevant brain networks associated to core cognitive functions, we present a novel interactive virtual reality system that aids in 3D visualization of precise electrode placement within cortical and subcortical regions of the patient and facilitates dynamical functional connectivity analysis of the aforementioned networks. The system is an extension of the BrainX tool [1–3], developed at the Laboratory for the Synthetic, Perceptive, Emotive and Cognitive Systems (SPECS). Methods Data were collected from an epileptic patient implanted with 125 depth electrodes for monitoring purposes in the context of a study about active/passive navigation within a virtual maze. Electrode placement have been reconstructed in 3D within BrainX and superimposed to the cortical brain structural network of 998 nodes obtained from [4], and a semi-transparent volumetric representations of anatomical regions (Fig. 1). Recorded EEG time-series are replayed on the reconstructed network and graph metrics analyzed with the embedded BCT toolbox [5].