Authors :
Presenting Author: Takamasa Mitsumatsu, MD – Department of Pediatrics, Nagoya University Graduate School of Medicine
Yuji Ito, MD.PhD – Department of Pediatrics, Nagoya University Graduate School of Medicine; Yuki Maki, MD.PhD – Department of Pediatrics, Nagoya University Graduate School of Medicine; Hiroyuki Yamamoto, MD.PhD – Department of Pediatrics, Nagoya University Graduate School of Medicine; Fumi Sawamura, MD – Department of Pediatrics, Nagoya University Graduate School of Medicine; Satoshi Maesawa, MD.PhD – Department of Neurosurgery, Nagoya University Graduate School of Medicine; Epifanio Bagarinao, PhD – Brain & Mind Research Center, Nagoya University; Tsu Yoshimura, MD – Department of Pediatrics, Nagoya University Graduate School of Medicine; Hajime Narita, MD – Department of Pediatrics, Nagoya University Graduate School of Medicine; Ryosuke Suzui, MD – Department of Pediatrics, Nagoya University Graduate School of Medicine; Sumire Kumai, MD – Department of Pediatrics, Nagoya University Graduate School of Medicine; Anna Shiraki, MD – Department of Pediatrics, Nagoya University Graduate School of Medicine; Tomohiko Nakata, MD.PhD – Department of Pediatrics, Nagoya University Graduate School of Medicine; Hiroyuki Kidokoro, MD.PhD – Department of Pediatrics, Nagoya University Graduate School of Medicine; Jun Natsume, MD.PhD – Department of Developmental Disability Medicine, Nagoya University Graduate School of Medicine
Rationale:
Acute encephalopathy is
characterized by impaired consciousness and often associated with seizures during the course of infectious diseases in children. Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) is a common type of the pediatric acute encephalopathies in Japan. We have previously reported that the incidence of epilepsy after AESD is as high as 23 percent. Epileptic spasms and startle focal seizures are common seizure types. In the present study, we evaluated epileptic focus and networks in patients with epilepsy after AESD using simultaneous EEG and fMRI (EEG-fMRI) to clarify the pathophysiology of the post-encephalopathic epilepsy.
Methods:
Two children with epilepsy after AESD underwent EEG-fMRI. Statistically significant blood oxygenation level-dependent (BOLD) responses related to interictal epileptiform discharges were analyzed by using an event-related design of four hemodynamic response functions with peaks at 3, 5, 7, and 9 seconds.
Results:
Case 1 developed focal seizures at 10 years old, one year after the onset of AESD. The daily focal seizures starting with abnormal sensation in one hand on each side, followed by weakness in the ipsilateral upper extremity, persisted. MRI showed atrophy of the left temporal and parietal lobes, and FDG-PET revealed hypometabolism in these areas. EEG-fMRI showed BOLD changes related to bilateral frontal and left temporal spikes and slow waves. Positive BOLD changes were observed in the bilateral frontal lobes, bilateral temporal lobes, and left parietal lobe. In deep brain structures, BOLD changes were observed in the bilateral thalami, caudate nuclei, and putamina. Case 2 developed epileptic spasms at two years old, one month after the onset of AESD. MRI showed mild diffuse cerebral atrophy, and FDG-PET revealed diffuse cortical hypometabolism. The seizures resolved by adrenocorticotropic hormone therapy but recurred. He underwent total corpus callosotomy (CC) at three years old. EEG-fMRIs were performed before and after the CC. EEG-fMRI before the CC showed BOLD changes related to the diffuse polyspikes and slow waves. Positive BOLD changes were observed in the bilateral frontal and temporal lobes. BOLD changes were also observed in the bilateral thalami, caudate nuclei, and putamina. EEG-fMRI after the CC showed BOLD changes related to the spikes and slow waves in the temporal and parietal regions of each of the left and right sides. Positive BOLD changes were localized to the part of bilateral frontal lobes and temporal lobes. In deep brain structures, BOLD changes remained in the brainstem only. After the CC, epileptic spasms have resolved, and neurodevelopmental improvement has been observed.Conclusions:
In the epilepsy after AESD, the presence of widespread epileptic networks from the cortices to deeper structures was suggested. CC is effective in disconnecting the epileptic networks of epileptic spasms in the post-encephalopathic epilepsy.
Funding: This work was supported by the Japan Agency for Medical Research and DevelopmentI(AMED).