title: Lateralization of human focal epilepsy by 31P magnetic resonance spectroscopic imaging.
abstract: We attempted to lateralize the epileptogenic focus (seven temporal lobe hippocampal foci, one frontal lobe focus) in medically refractory unilateral complex partial seizures, using noninvasive 31P magnetic resonance spectroscopic imaging (MRSI) blindly and interictally to compare hippocampal or frontal regions. The seizure foci were more alkaline (intracellular pH = 7.17 +/- 0.03) compared with the contralateral region (7.06 +/- 0.02, p < 0.01) in all eight cases; the inorganic phosphate was relatively increased (240 +/- 50% of contralateral, seven of eight cases, p < 0.01); and phosphomonoesters were relatively reduced (68 +/- 9% of contralateral, seven of eight cases, p < 0.01). Other phosphorus metabolites were symmetric (+/- 10%). 31P MRSI correctly lateralized the seizure focus in all eight cases. By comparison, imaging correctly lateralized four cases and SPECT, two cases. In conclusion, 31P MRSI is a useful tool for the noninvasive clinical assessment of focal epilepsy and can accurately lateralize the epileptogenic focus.
authors.affiliation: MR Unit, Department of Veterans Affairs Medical Center, San Francisco, CA.
authors.forename: J W
authors.initials: JW
authors.lastname: Hugg
authors.forename: K D
authors.initials: KD
authors.lastname: Laxer
authors.forename: G B
authors.initials: GB
authors.lastname: Matson
authors.forename: A A
authors.initials: AA
authors.lastname: Maudsley
authors.forename: C A
authors.initials: CA
authors.lastname: Husted
authors.forename: M W
authors.initials: MW
authors.lastname: Weiner
mesh_terms: D000328:Adult; D001921:Brain / Q000378:metabolism / Q000473:pathology*; D017029:Epilepsy, Complex Partial / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000378:metabolism; D006801:Humans; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D010758:Phosphorus; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D010758:Phosphorus