Yonsei Med J.  2013 May;54(3):572-577. 10.3349/ymj.2013.54.3.572.

Quantitative Analysis of Simultaneous EEG Features during PET Studies for Childhood Partial Epilepsy

• Hur YJ
• Lee JS
• Lee JD
• Yun MJ
• Kim HD

• KMID: 1727866
• DOI: http://doi.org/10.3349/ymj.2013.54.3.572

Abstract

PURPOSE
To demonstrate the significance of simultaneous electroencephalography (EEG) recording during 2-deoxy-2-[18F] fluoro-D-glucose (FDG)-positron emission tomography (PET) in childhood partial epilepsy.
MATERIALS AND METHODS
We included 46 children with partial epilepsy who underwent simultaneous EEG during PET. We compared the epileptogenic area of several EEG features including epileptiform discharges, focal polymorphic slow waves, and electrographic seizures, with the abnormal metabolic region on PET. We also compared the epileptogenic area of simultaneous EEG and PET with findings on magnetic resonance imaging (MRI) and video/EEG, as well as the histopathological diagnosis of the resected cortical area, in eight patients who underwent surgical resection of the epileptogenic area.
RESULTS
Hypometabolic regions on interictal PET were concordant with epileptogenic areas of epileptiform discharges and focal polymorphic slow waves, according to their frequency and/or severity, with odds ratios of 1.35 and 1.81, respectively (p<0.05). Hypermetabolic PET was also concordant with epileptogenic areas of ictal events longer than 20 seconds during the period of FDG uptake. Among the eight patients who underwent surgical resection, six patients, including two with non-lesional MRI, had concordant EEG and PET findings, were confirmed pathologically, and became seizure-free after surgery.
CONCLUSION
Simultaneous EEG is useful in identifying epileptogenic areas due to a high concordance with abnormal PET metabolic areas. Moreover, simultaneous EEG may also prevent false lateralization of PET from postictal and mixed metabolism during ictal events, as well as abnormal hypermetabolism, during frequent interictal epileptiform discharges.

Keyword

Positron-emission tomography; electroencephalography; epilepsy

MeSH Terms

Adolescent
Child
Electroencephalography/*methods
Epilepsies, Partial/*diagnosis/radionuclide imaging/surgery
Female
Humans
Logistic Models
Magnetic Resonance Imaging
Male
Positron-Emission Tomography/*methods
Treatment Outcome

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