Sourcerer IC: A Web-Based Integrative Multi-Modal Workflow for Epilepsy Surgical Planning

Abstract The overarching goal of this project is to create software that improves the use of intracranial EEG to qualify patients with medication-resistant epilepsy for neurosurgery. One million people in the US suffer from continual seizures that are not controlled by medication. The current estimate is that half of these could be treated effectively by surgical resection of the epileptic cortical tissue, and yet the majority of them will not receive the surgery (Engel & Wiebe, 2012). There are 200 Comprehensive Epilepsy Centers in the US that are certified to provide both the epilepsy resection and the multimodal presurgical evaluation (clinical semiology, neuropsychological assessment, EEG, MRI, PET, and intracranial or icEEG). A problem for this evaluation is the software for integrating the multiple imaging and assessment modalities in the presurgical workup to allow confidence in the neurosurgical plan. The localization of the icEEG electrodes is often problematic because of brain shift (movement and deformation of the brain from the preoperative imaging to the postoperative CT used for electrode position imaging). With recent advances in dense array EEG (dEEG) with individual head conductivity models, electrical source imaging can provide noninvasive estimates of the seizure onset zone, which could then guide more focused and effective icEEG probes, and potentially more confident and limited neurosurgical resections. The present SBIR research builds on our extensive experience with icEEG electrode localization, multimodal neuroimage registration, dEEG source imaging, and user interface design to create Sourcerer IC, a software platform optimized for bringing multiple forms of evidence to interpret icEEG measures and improve the localization of the seizure onset zone. The key innovations of this project are: the integration of multimodal neuroimaging data (MRI, dwMRI, fMRI, PET) registered precisely with structural MRI in a DICOM format for export to the neurosurgeon’s neuronavigator software; the capacity for noninvasive dEEG source localization of spikes and seizure onset with individual head conductivity models in preparation for icEEG electrode placement (as validation rather than exploration); the correction of brain shift due to surgical implanting of icEEG electrodes by registering the postoperative CT to the preoperative MRI; and perhaps most importantly, the integration of all components of the presurgical workup within an intuitive and usable software workflow with full quality system regulation and validation following FDA guidelines. Sourcerer IC will build on the many years of experience with Yale’s BioImage Suite, such that physicians and technicians access their components of the workflow through secure web interfaces, and the networked database maintains and integrates all transactions to coordinate computational as well as data resources for efficient completion, review, and implementation of an optimized neurosurgical plan.