Flumazenil PET and Decision Making in the Surgical Management of Non-Lesional Epilepsy

Jeffrey G. Ojemann

University of Washington, Seattle, WA
Website

Grant Program:

David Mahoney Neuroimaging Program

Funded in:

June 2000, for 8 years

Funding Amount:

$99,900

Investigator Biographies

Jeffrey G. Ojemann

Associate Professor of Neurological Surgery

University of Washington

Hypothesis

Hypothesis

Hypothesis:
To answer whether a newer imaging technique, flumazenil positron emission tomography (flumazenil-PET), can impact decision-making processes in the evaluation of patients for surgical treatment of intractable epilepsy.

Goals:
1. Flumazenil PET will be shown to alter the decision-making processes in patients with medically intractable epilepsy. The introduction of Flumazenil PET findings will provide information that will either alter surgical strategies or expand the population eligible for invasive monitoring.
2. Flumazenil PET abnormalities will correlate with electrographic abnormalities.
3. The resection of flumazenil-PET abnormalities will be predictive of seizure and cognitive outcome.

Methods:
Patients who are either candidates for invasive monitoring for evaluation of intractable seizures or who have been determined to be ineligible for resective surgery will undergo flumazenil PET studies. The results of the studies will be compared to the clinical care decided upon without this information, and the resulting proposed clinical plan compared with and without the flumazenil data. Patients who are found to be multifocal will also be studied to determine the ability of flumazenil to identify patients who are not good candidates for resective surgery.

Findings:
We have documented the incidence of useful information obtainable by a flumazenil-PET scan. In at least 20% of the cases we studied, new information was obtained that could not be determined by other imaging modalities. This may influence surgical plans in the future. As a next step, we are preparing an application to the FDA to allow us to use flumazenil-PET in the clinical evaluation of adults and children with non-lesional, medically intractable epilepsy. This is the next step in making this novel technology widely available to epilepsy surgery programs.

Selected Publications

Eisenman L.N., Pu Y., Mintun M.A., Vermani N., Gilliam F.G., Attarian H.P., Fessler A.J., Trevathan N.E., and Ojemann J.G.   The utility of flumazenil PET in the presurgical evaluation of extratemporal versus mesial temporal lobe epilepsy. Epilepsia 43 (suppl 7):247, 2002.

Pu Y., Mintun M.A., Trevathan N.E., Gilliam F.G., Moerlein S.M., and Ojemann J.G.   11C-Flumazenil PET in the localization of the focus of epileptogenicity and surgical decision-making in intractable, extra-limbic epilepsy.  Radiology 225:464 (suppl), 2002.