Hisashi Itabashi1, Kazutaka Jin2, Masaki Iwasaki3, Eiichi Okumura4, Akitake Kanno5, Kazuhiro Kato4, Teiji Tominaga3, Ryuta Kawashima5, Nobukazu Nakasato4. 1. Department of Epileptology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan; Department of Pediatrics, Dokkyo Medical University Koshigaya Hospital, Koshigaya, Saitama, Japan. 2. Department of Epileptology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan. Electronic address: jink@med.tohoku.ac.jp. 3. Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan. 4. Department of Epileptology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan. 5. Department of Functional Brain Imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi, Japan.
Abstract
OBJECTIVE: Small focal cortical dysplasia (FCD) may be ambiguous or overlooked on magnetic resonance (MR) imaging. Source localization of EEG and magnetoencephalography (MEG) spikes was evaluated to confirm the diagnosis of small FCD. METHODS: This study included 6 epilepsy patients with a single small lesion on MR imaging suggesting FCD within a single gyrus among 181 consecutive epilepsy patients admitted to our epilepsy monitoring unit over 27 months. Stereotypical interictal spikes were detected on simultaneous EEG and MEG recordings and the onset-related source of averaged spikes was estimated. RESULTS: All 6 patients had unique clinical characteristics as follows: leg sensori-motor seizures in 5 patients and eye version in 1 patient; a small MR imaging lesion suggesting FCD in the dorsal peri-rolandic region, which had been overlooked until our evaluation; and both EEG and MEG dipoles were estimated adjacent to the MR imaging lesion. CONCLUSIONS: Source localization of EEG and MEG spikes can confirm the diagnosis of FCD based on a single small MR imaging lesion, which was overlooked by previous examination of MR images. SIGNIFICANCE: Examination of MR images should be based on spike source localization as well as seizure semiology to identify subtle MR imaging abnormalities.
OBJECTIVE: Small focal cortical dysplasia (FCD) may be ambiguous or overlooked on magnetic resonance (MR) imaging. Source localization of EEG and magnetoencephalography (MEG) spikes was evaluated to confirm the diagnosis of small FCD. METHODS: This study included 6 epilepsypatients with a single small lesion on MR imaging suggesting FCD within a single gyrus among 181 consecutive epilepsypatients admitted to our epilepsy monitoring unit over 27 months. Stereotypical interictal spikes were detected on simultaneous EEG and MEG recordings and the onset-related source of averaged spikes was estimated. RESULTS: All 6 patients had unique clinical characteristics as follows: leg sensori-motor seizures in 5 patients and eye version in 1 patient; a small MR imaging lesion suggesting FCD in the dorsal peri-rolandic region, which had been overlooked until our evaluation; and both EEG and MEG dipoles were estimated adjacent to the MR imaging lesion. CONCLUSIONS: Source localization of EEG and MEG spikes can confirm the diagnosis of FCD based on a single small MR imaging lesion, which was overlooked by previous examination of MR images. SIGNIFICANCE: Examination of MR images should be based on spike source localization as well as seizure semiology to identify subtle MR imaging abnormalities.
Authors: Naoaki Tanaka; Christos Papadelis; Eleonora Tamilia; Michel AlHilani; Joseph R Madsen; Phillip L Pearl; Steven M Stufflebeam Journal: Pediatr Neurol Date: 2018-03-15 Impact factor: 3.372
Authors: Rupa Radhakrishnan; James L Leach; Francesco T Mangano; Michael J Gelfand; Leonid Rozhkov; Lili Miles; Hansel M Greiner Journal: Pediatr Radiol Date: 2016-04-25