title: Glutamate imaging (GluCEST) lateralizes epileptic foci in nonlesional temporal lobe epilepsy.
abstract: When neuroimaging reveals a brain lesion, drug-resistant epilepsy patients show better outcomes after resective surgery than do the one-third of drug-resistant epilepsy patients who have normal brain magnetic resonance imaging (MRI). We applied a glutamate imaging method, GluCEST (glutamate chemical exchange saturation transfer), to patients with nonlesional temporal lobe epilepsy based on conventional MRI. GluCEST correctly lateralized the temporal lobe seizure focus on visual and quantitative analyses in all patients. MR spectra, available for a subset of patients and controls, corroborated the GluCEST findings. Hippocampal volumes were not significantly different between hemispheres. GluCEST allowed high-resolution functional imaging of brain glutamate and has potential to identify the epileptic focus in patients previously deemed nonlesional. This method may lead to improved clinical outcomes for temporal lobe epilepsy as well as other localization-related epilepsies.
authors.affiliation: Penn Epilepsy Center, Department of Neurology, Hospital of the University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Kathryn Adamiak
authors.initials: KA
authors.lastname: Davis
authors.affiliation: Center for Magnetic Resonance & Optical Imaging, Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Ravi Prakash Reddy
authors.initials: RP
authors.lastname: Nanga
authors.affiliation: Penn Image Computing & Science Lab, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Sandhitsu
authors.initials: S
authors.lastname: Das
authors.affiliation: Penn Epilepsy Center, Department of Neurology, Hospital of the University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Stephanie H
authors.initials: SH
authors.lastname: Chen
authors.affiliation: Penn Epilepsy Center, Department of Neurology, Hospital of the University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Peter N
authors.initials: PN
authors.lastname: Hadar
authors.affiliation: Penn Epilepsy Center, Department of Neurology, Hospital of the University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: John R
authors.initials: JR
authors.lastname: Pollard
authors.affiliation: Department of Neurosurgery, Hospital of the University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Timothy H
authors.initials: TH
authors.lastname: Lucas
authors.affiliation: Department of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Russell T
authors.initials: RT
authors.lastname: Shinohara
authors.affiliation: Penn Epilepsy Center, Department of Neurology, Hospital of the University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Litt
authors.affiliation: Center for Magnetic Resonance & Optical Imaging, Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Hari
authors.initials: H
authors.lastname: Hariharan
authors.affiliation: Center for Magnetic Resonance & Optical Imaging, Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Elliott
authors.affiliation: Center for Magnetic Resonance & Optical Imaging, Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: John A
authors.initials: JA
authors.lastname: Detre
authors.affiliation: Center for Magnetic Resonance & Optical Imaging, Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Ravinder
authors.initials: R
authors.lastname: Reddy
mesh_terms: D000328:Adult; D000069279:Drug Resistant Epilepsy / Q000175:diagnosis* / Q000601:surgery*; D004828:Epilepsies, Partial / Q000175:diagnosis / Q000601:surgery; D004833:Epilepsy, Temporal Lobe / Q000175:diagnosis / Q000601:surgery; D005260:Female; D018698:Glutamic Acid; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D059906:Neuroimaging / Q000379:methods*
chemical_list: D018698:Glutamic Acid