Complex partial seizures in children: ictal manifestations and their relation to clinical course.

We analyzed complex partial seizures in 38 children aged 0 to 13 years, using simultaneous EEG-VTR recording. In infants, seizure duration was longer, automatisms were less purposeful and more common in the oral area, and convulsive movements were frequently seen and more extensive in comparison with older children. In ictal EEG, spiky components frequently appeared in infants. Parietal or occipital ictal foci were more often associated with mental or physical abnormalities than were frontal or central foci. Extensive convulsive movements were inversely proportional to seizure prognosis in older children. Interictal paroxysmal discharges were observed less frequently in infants.

Developmental changes of pattern reversal visual evoked potentials.

Analysis of developmental changes in pattern reversal visual evoked potentials (PVEPs) was performed on 141 normal children ranging in age from 1 month to 19 years 4 months. The stimulus was a black and white checkerboard pattern on a television screen, and the check edge subtended 50 min of retinal arc. The major positive peak (P2) was observed in all subjects, and the incidence of other peaks tended to increase with age. The P2 latency decreased rapidly during the first six months of life and reached a constant value after the age of 2 years. The P2 latency with monocular stimulation was significantly longer than that with binocular stimulation in most age groups. Developmental changes of the N1-P2 or P2-N2 amplitudes were unclear, and the standard deviation of the amplitude in each age was too large for clinical application. The P2 latency with binocular stimulation was shorter for females than for males only at the age of 8-11 years.

Auditory brainstem response: a comparative study of ipsilateral versus contralateral recording in neurological disorders of children.

The auditory brain stem response (ABR) was studied in 103 normal and 90 neurologically abnormal children. The ABR was recorded simultaneously in Cz to the mastoid both ipsilateral and contralateral to the stimulated ear. A comparison between the ipsilateral and contralateral recording demonstrated that contralateral recording resulted in a small increase in the latency of peak V, whereas peak III showed a small latency reduction in the large majority of normal and neurologically abnormal children despite relatively large intersubject variability. There were some cases (cerebral palsy, infantile spasms) which demonstrated abnormal ABR only on contralateral recordings. Since most averaging systems have two channels, it is desirable to record the ABR simultaneously on bilateral recordings.

Seizure prognosis and EEG evolution in complex partial seizures of childhood onset.

We studied the clinical course and seizure prognosis of 126 children with complex partial seizures regularly followed up for more than 4 years in our clinic. Clinical and EEG features of 63 seizure-free patients were compared with those of 63 patients with persistent seizures. The features contributing to poor prognosis were 1) mental retardation, 2) a history of status epilepticus and 3) abnormal basic rhythm in EEG. CT abnormality, a history of febrile convulsions (FC), the clustering of seizures and association with other types of seizures did not influence prognosis. We divided the patients into four groups according to the evolutionary pattern of seizure discharges: Group A, 55 (43.7%) patients with spike focus always fixed in the same region; Group B, 20 (15.9%) patients with wandering foci; Group C, 10 (7.4%) patients with multifocal spikes; and group D, 41 (32.5%) patients with no focal discharges. There was no difference in seizure prognosis among these four groups, but the patients with a focus in the anterior temporal region in Group A evidenced the worst prognosis.

Benign complex partial epilepsies in infancy.

Nine infants with benign complex partial seizures, diagnosed by simultaneous electroencephalogram and video recordings, are described. At mostly 3-10 months of age, these infants demonstrated clusters of seizures which consisted of motion arrest, decreased responsiveness, staring or blank eyes mostly with simple automatisms, and mild convulsive movements associated with focal paroxysmal discharges. The seizures were controlled easily with carbamazepine or phenobarbital and all patients remained seizure-free for more than 3 years. Four patients had family histories of benign types of infantile convulsions. Interictal electroencephalogram and psychomotor development were normal in all patients.

Development of the beta activities in children: an EEG-topographical analysis.

We investigated the characteristics of beta activities during drowsiness and very light sleep in 61 children using topographical analysis. The average power of beta activities was posterior-dominant in infancy, and it became frontal-dominant as the age increased. These topographical changes occurred earlier in the low frequency bands than the high frequency bands. The total power of the high frequency bands was larger in infants, and with increasing age that of the low frequency bands predominated. The developmental changes of the beta activities considered to be induced by drugs were similar to those of children without drugs.

MRI findings in patients with symptomatic localization-related epilepsies beginning in infancy and early childhood.

We studied MRI findings in patients with symptomatic localization-related epilepsy (S-LRE) beginning in infancy and early childhood and their relation to some clinical features. MRI findings were investigated in 183 patients with S-LRE beginning before 6 years of age. S-LRE was defined as an epileptic syndrome manifesting with only partial seizures at least for a certain period during the clinical course, having specific neuroimaging abnormalities considered to be related to epileptic seizures, moderate or severe mental retardation, or cerebral palsy. The timing of injury was divided into the following four groups; prenatal, perinatal, postnatal and unknown. It was presumed prenatal in 56 patients (31%), perinatal in 25 (14%), postnatal in 32 (18%) and unknown in 70 (38%). The median age at the onset of partial seizures was 24 months in the congenital (prenatal and unknown) group, 39 months in the perinatal group and 25 months in the postnatal group. The onset of partial seizures was later in the perinatal group than in the congenital group. There were no significant differences in the other clinical characteristics among groups except for more frequent association of cerebral palsy in the perinatal group than in the congenital group. Our study suggests that congenital (prenatal and unknown group) disorders may be most common in patients with S-LRE beginning in infancy and early childhood. The onset of partial seizures occurred later in the perinatal group.

[A case of unilateral moyamoya disease presenting with hemichorea].

We reported a 12-year-old boy with unilateral moyamoya disease whose initial and predominant manifestation was hemichorea. Neurological examinations revealed chorea in his left upper extremity and muscle hypotonia in his left upper and lower extremities. Cranial MRI showed moyamoya vessels only in the right basal ganglia and infarction in the white matter of the right frontal lobe. Right carotid angiography revealed stenosis in the distal part of internal carotid artery, and in the proximal part of anterior and middle cerebral arteries with moyamoya vessels. Left carotid angiography showed normal findings. He was diagnosed as a suspected case of moyamoya disease (unilateral moyamoya disease) according to the diagnostic criteria proposed by the Research Committee on Moyamoya Disease of the Ministry of Health and Welfare of Japan. His chorea responded to haloperidol but encephalo-duro-arterio-synangiosis on the right side improved all symptoms. Chorea occurs in some patients with moyamoya disease. Hypofunction of the striatal indirect pathway is suggested as the cause of chorea. In this case an ischemic lesion in the right striatum may have caused hypofunction of the pathway and developed chorea and hypotonia.

[Suspected germ cell tumor in bilateral basal ganglia with progressive dystonia].

We report an 11-year-old boy with left pyramidal signs followed by progressive dystonia, mental deterioration, bradykinesia and bradyarthria. Evaluation included a CT scan which showed bilateral lesions in the basal ganglia, and an elevated serum B-HCG. Those findings suggested a germ cell tumor. The patient was treated with radiation therapy with improvement in neurologic deficits, decreased size of the lesions on CT and a decline in serum B-HCG. The clinical response to radiation treatment is compatible with a germ cell tumor.

[Long-term follow-up of absence epilepsy].

This study dealt with 58 patients with absence, of whom 46 patients had started with absence and 12 with generalized tonic-clonic seizures (GTCs). Only those patients followed up for more than five years were included, and 30 patients (51.7%) were over eighteen years of age (up to 33). All patients received the present standard medication with ethosuximide and valproate in this study. In each case the diagnosis was confirmed by clinical observation and the typical EEG pattern. A seizure-free interval of at least 1 year was defined as seizure cessation for absence, and a seizure-free interval of at least 2 years for GTCs. Thirty-eight out of 43 patients (88.4%) with absence at onset (group A) and 18 out of 22 (81.8%) older than 18 years became seizure free. Only 8 of 15 (53.3%) patients with initial GTCs (group B) and 5 of 8 (62.5%) over 18 years became seizure free. In all, about 80% of the patients with absence seizures became seizure free as did those who were followed beyond 18 years of age. Out of 15 patients with initial GTCs, 8 of 10 (80%) patients who developed absence seizures later (group B-1) became seizure free, whereas none of 5 patients who had absence and GTC at the same time (group B-2) did. The social status was mainly favorable, even if seizures were uncontrolled. Adequate predictable factors for the development of GTCs were lacking, but the clinical courses in patients of group B-1 resembled those of group A and were rather benign.

Partial seizures evolving to infantile spasms.

We describe the clinical and electroencephalographic (EEG) manifestations of four patients with simultaneous EEG-video-telemetry recording (VTR) documented partial seizures evolving to infantile spasms. Clinical manifestations of the partial seizures included cessation of activity, staring, automatisms, increased limb tone, and laughter. In each case, partial seizures were followed by a cluster of infantile spasms. Infantile spasms preceded by partial seizures have not been previously documented.

Magnetic resonance imaging in complex partial seizures.

Magnetic resonance imaging (MRI) and computed tomography (CT) were performed on 45 patients with intractable complex partial seizures. MRI was performed with a superconducting whole-body scanner operating at 0.5 tesla (T) and 1.5 T. In patients with temporal lobe epilepsy, 8 of 24 patients had abnormal CT, but 16 of 24 patients showed abnormal MRI. 1.5 T MRI detected more abnormality than 0.5 T MRI when CT was normal. In patients with frontal lobe epilepsy, 5 of 7 patients had normal CT and MRI. In 2 other patients, MRI demonstrated an arachnoid cyst and increased signal intensity area on the T2-weighted images which were not detected by CT. In patients with occipital lobe epilepsy, 5 of 6 patients show abnormal CT and MRI. In patients with tuberous sclerosis, MRI revealed some increased signal intensity areas on the T2-weighted images in the occipital and temporal lobe, which were not detected by CT. Most surface EEG foci corresponded with the side of MRI abnormality. These data indicate that MRI is more informative than CT in complex partial seizures. MRI is the imaging technique of choice in the diagnosis of complex partial seizures.

Decrease of N-acetylaspartate after ACTH therapy in patients with infantile spasms.

Apparent brain atrophy has been frequently observed at CT and MRI after ACTH therapy in patients with infantile spasms. There are several hypotheses to explain ACTH-induced brain shrinkage: 1) a catabolic effect of ACTH on brain tissue, 2) a mineralocorticoid effect resulting in a loss of water and 3) an increase in cerebrospinal fluid (CSF) pressure compressing the brain. An average of 0.21 +/- 0.03 mg/kg of ACTH was administered to nine patients over a period of 14 to 17 days. Water content and concentrations of N-acetylaspartate (NAA), creatine and phosphocreatine (Cr + PCr), and choline (Cho) were measured before, immediately after, and several months after the ACTH therapy by using in-vivo 1H magnetic resonance spectroscopy (MRS). Only NAA concentration exhibited a significant change during the study (6.6 +/- 1.5 mmol/kg, 5.4 +/- 1.1, and 7.0 +/- 1.5, p = 0.017). There was no significant change in Cr + PCr, in Cho, or in water content. These data suggest catabolic effects of ACTH on brain tissue, such as cell loss, decrease in NAA synthesis in mitochondria, and leakage of NAA from cell membrane.

Epilepsies of neonatal onset: seizure type and evolution.

Most neonatal seizures are occasional seizures and not true epilepsy. This study investigates seizure types of true neonatal epilepsies and their evolution with development. Seventy-five children with epilepsies of onset within 1 month of life, who were examined between 1970 and 1995, and whose seizure types could be confirmed with ictal EEG recordings, were studied. The patients were followed up for a minimum of 3 years and the evolution of epileptic syndromes was investigated. Sixty-three (84%) of 75 patients had partial seizures, while nine had generalized seizures, and only three had both generalized and partial seizures. Twenty-three of 24 neonates with benign familial or non-familial neonatal convulsions presented with partial seizures; these syndromes should not necessarily be categorized into generalized epilepsy as they are in the present International Classification. Age-dependent changes were a common feature of symptomatic neonatal epilepsies. Eighteen (41%) of 44 patients with symptomatic epilepsies of neonatal onset developed West syndrome in infancy. Fifteen (83%) of these 18 patients presented with symptomatic localization-related epilepsy in the neonatal period. In seven of these 15 patients, West syndrome was followed by localization-related epilepsy. Symptomatic localization-related epilepsy with transient West syndrome in infancy is another type of age-dependent epileptic syndrome.

Transplacental effect of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) on brain dopaminergic neurons in the mouse. An immunohistochemical study.

Immunohistochemical studies of monoamine neurons were performed to evaluate toxic effects of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) on young adult mice and compare them with those of their offspring. Mice, 9-11 weeks old (C57BL/6J), injected subcutaneously with a large dose of MPTP (17 mg/kg per day) during pregnancy on Day 9 and 12 of gestation (G9 and G12) miscarried and were examined at 13 weeks of age. Conversely, mice treated during pregnancy with sequential low dose of MPTP (2.8 mg/kg per day at G9-G17 for 8 days) successfully delivered their babies and were examined at the age of 15 weeks. Baby mice were examined at 1 and 6 weeks of age. The tyrosine hydroxylase-, aromatic L-amino acid decarboxylase- and dopamine (DA)-immunoreactive density of caudoputamen was reduced in 13-week-old mice treated with high dose of MPTP but not in the 15-week-old mothers exposed to a low dose of MPTP as compared to their respective controls. The DA-immunoreactive density of the caudoputamen was the only staining that was reduced in both 1- and 6-week-old baby mice. In conclusion, these results demonstrate that MPTP injected to pregnant mice causes a DA depletion in the striatum of their offspring indicating a transplacental effect of MPTP. The findings also indicate that fetal brain is more susceptible to MPTP toxicity than the brain of young pregnant mice.