Intrinsic Optical Imaging Study to Map Neocortical Seizure in Human Epilepsy Patients
Intrinsic Optical Imaging Study to Map Neocortical Seizure in Human Epilepsy Patients
The purpose of this study is to develop a technique for the intraoperative identification of
 human functional and epileptiform cortex using intrinsic signal imaging. The investigators
 propose that the ability to optically monitor neuronal activity in a large area of cortex in
 "real-time" will be a more sensitive and time-saving method than the electrical methods
 currently available. The applications of this technique will not only theoretically increase
 the safety and efficacy of many of neurosurgical procedures, but will be useful as an
 investigational tool to study human cortical physiology.
Epilepsy is a disease affecting 1-2% of the population. Currently, the only known cure for
 epilepsy is surgery, which is much more effective at eliminating seizures arising from the
 medial temporal lobe compared with the neocortex. The problem with neocortical epilepsy is
 that the population of neurons underlying each epileptiform discharge varies over time. In
 addition, the spatial relationship between interictal events and the ictal onset zones, which
 are critical in defining the region of epileptogenesis, is not well understood and essential
 to the surgical treatment of epilepsy. Electrophysiological recording methods, although
 currently the "gold standard" in mapping epilepsy, are inadequate to address these questions
 based on restrictions due to volume conduction or sampling limitations. Optical recording
 techniques can overcome many of these limitations by sampling large areas of cortex
 simultaneously to provide information about blood flow, metabolism and extracellular fluid
 shifts that are intimately related to excitatory and inhibitory neuronal activity. In fact,
 optical recordings may actually be more sensitive to certain aspects of epileptic activity
 than electrophysiologic recordings. The goal will be to translate these findings into the
 operating room and map human neocortical epilepsy with the same optical techniques. Outcome
 following surgical resections to treat neocortical epilepsy will be correlated with the
 optical maps to determine the utility of intrinsic signal imaging in guiding brain surgery.
 These experiments will set the groundwork for implementing optical recordings in general
 clinical practice as a novel technique for mapping and predicting human seizures.
Inclusion Criteria:

 -  Medically intractable epilepsy

 -  Subjects undergoing neurosurgical operations requiring cortical mapping

 Exclusion Criteria:

 -  Subjects NOT undergoing neurosurgical operations requiring cortical mapping.