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Background: The influence of physiological and methodological factors on recordings of brainstem auditory evoked potentials (BAEPs) is greater in children than in adults., Objective: To collect and evaluate BAEP data in normal children, and measure intra- and inter-laboratory variability., Methods: Seven hundred and fifty unselected BAEP recordings were collected and evaluated from children ranging from neonates to 14-year-olds by eight laboratories in Italy., Results: In newborns, three laboratories showed satisfactory concordance; wave I was more broadly distributed than wave V and IPL I-V. The evaluation of pooled BAEP data from the older children showed that laboratories with age-matched data gave overlapping results; those with unmatched-age data differed significantly. The sound intensities of the laboratories did not significantly affect absolute BAEP latencies or IPLs. Females had shorter latencies than males; the difference was not significant. A single exponential regression model was an adequate but not the best predictor of normal data., Conclusions: The pooled data were consistent with the physiological maturation of the brainstem acoustic pathway. The BAEPs was reliably normalised using the natural logarithm of age. The differences between Centres were related to sample size, measurement accuracy, and inclusion and selection criteria., Significance: The creation of multicentre common database from an unmatched data collection is feasible and reliable enough for clinical diagnosis and multicentre clinical research.

Purpose: To evaluate the long-term outcome of patients with pattern-sensitive epilepsy., Methods: We prospectively studied 35 patients (21 females and 14 males) with pattern-sensitive epilepsy (follow up > or = 5 years; mean 13.9; range 6.4 - 27.6). All cases had regular clinical examinations and serial electroencephalographic (EEG) recordings. Photosensitivity and pattern sensitivity were ascertained neurophysiologically in all cases. Outcome was evaluated according to the following variables: duration of photosensitivity, rate of remission (seizure-free period > or = 2 years), withdrawal of therapy, and recurrence after drug discontinuation., Results: The epilepsy was generalized in 18 cases (17 idiopathic, one symptomatic) and partial in 17 (13 idiopathic, four symptomatic). Sixteen patients (46%) had a family history of seizures. The mean age at the last examination was 21.4 years (range 11.2-35.5 years). Five patients (14%) had only reflex seizures. The most common type of spontaneous seizures was generalized (60%), whereas reflex seizures were more frequently partial (74%). Mean epilepsy duration was 8.7 +/- 6.3 years. Patients with only reflex seizures were instructed to avoid precipitating stimuli and were not treated with antiepileptic drugs. Treatment was gradually withdrawn in 10 out of 30 treated patients, with relapse in only two cases. At the end of follow up, 28 patients (80%) were seizure-free., Conclusion: The long-term outcome of patients with pattern-sensitive epilepsy indicates a good prognosis with a favorable course for both spontaneous and reflex seizures.

This study attempted to better define clinical and EEG features for differential diagnosis between epilepsy and migraine in children with occipital epileptiform EEG abnormalities. We studied 126 children (57 males, 69 females; age 4-18 years) suffering from epilepsy (63), migraine (43) or both (20). Patients were selected because of the presence of epileptiform abnormalities in the occipital regions on their EEG at rest. Differences among groups were statistically analyzed (Pearson chi square; ANOVA) for sex, age at onset of seizures and migrainous attacks, family history, ictal signs and symptoms, EEG at rest (unilateral vs bilateral distribution of epileptiform abnormalities), and EEG during Hyperventilation (HV) and Intermittent Photic Stimulation (IPS). Significant differences were found in family history, ictal signs and symptoms, EEG at rest and during activation tests. A family history of epilepsy, visual symptoms such as colored hallucinations and micro/macropsias, frequently associated with clinical signs in the visual system (eye deviation, nystagmus), unilateral EEG abnormalities, and abnormal response to IPS were closely related to diagnosis of epilepsy. On the other hand, a family history of migraine, visual symptoms such as amaurosis and scotomata, without evident clinical signs, bilateral EEG abnormalities, and no changes during IPS were significantly related to migraine. In conclusion, these clinical and EEG differences should be considered in the differential diagnosis between epilepsy and migraine in children with occipital epileptiform EEG abnormalities.

We report a 10-year-old girl with reflex seizures characterized by visual and acoustic hallucinations, induced by visual and acoustic stimulations. The EEG showed atypical spike-wave discharges on the left temporo-occipital area, markedly activated by visual and acoustic stimuli (intermittent light, pattern-reversal stimulation and monoaural right pure tone). The patient was treated with carbamazepine and seizure stopped within 7 months. After 10 months from the start of the therapy she developed signs of systemic lupus erythematosus.

After having reported continuous localized EEG discharge during slow sleep (CLEDS) in six children with congenital encephalopathy, we observed a similar EEG picture in six children free from both neuropsychological and neuroradiological defects. They suffered from partial idiopathic epilepsy; five presented a familial disposition towards febrile seizures. Continuous paroxysmal activity during sleep was observed from 4.8 yrs to 4.11 yrs (mean age: 4.9 yrs). Spontaneous remission of CLEDS was observed in three cases after 2-25 months, but one or more relapses occurred in two cases, and five children are still suffering from CLEDS. Seizures were controlled by drugs in all cases. Deterioration of intelligence level, although not severe, was observed in one case, after 24 months of CLEDS.

A 14-year-old right-handed girl suffering from absence seizures from age 6 began to have reflex seizures elicited by reading and watching television when she was 13. Neurophysiological studies showed pattern sensitivity and photo-sensitivity. VEPs, obtained with flash and pattern reversal stimulation, were normal. This atypical form of reading epilepsy suggests an interaction of pattern vision and cognitive functions as precipitating stimuli in reflex seizures.

Continuous generalized spike-and-wave complexes occurring during slow-sleep were first observed in some children by Patry et al. (1971). A general review of the reported cases was made by Tassinari et al. (1984). We have observed a new clinical-EEGraphic picture. Spikes and spike-and-wave complexes localized to one hemisphere were recorded during at least 85% non-REM sleep both in 3 quadriplegic and in 3 hemiplegic mentally retarded children, aged from 2 years and 10 months to 11 years (mean age: 5 years and 2 months). Cyclic organization of sleep was almost normal. Wake EEG showed an epileptic focus. Brain CT showed midline defect and brain atrophy in quadriplegic patients, and a wide temporal-parietal porencephalic cyst in hemiplegic patients. This EEGraphic pattern was associated with a more pronounced mental impairment: neuropsychological improvement was observed in 2 cases, when continuous sleep discharges disappeared. As aforesaid, this picture seems to be related either to hemispheric or to midline brain defects. In our cases, sleep phase organization could be examined, while continuous generalized discharges occurring during sleep do not allow such a study.

Altered cognitive functioning has often been reported in patients with epilepsy. In our study we looked for quantitative correlation between the recurrence of Subclinical Spike-and-Wave Discharges (SSWD) during EEG recording, the scores on the intelligence test (WISC) and the electro-clinical characteristics of 29 epileptic children with subclinical discharges of generalized spike-and-wave complexes. In our sample we found a below-normal mean IQ, with greater impairment on performance than on verbal tasks. No clear quantitative correlation was found between the weighted scores on the various subtests and the "time density" of the spike-and-wave complexes. These findings suggest that the SSWD interfere with cognitive development (mainly with visuo-spatial and sensorimotor coordination abilities) and selectively impair some of the functions involved in the cognitive processes.

We studied recurrence risks and predictive factors of relapse after antiepileptic drug (AED) discontinuation in a prospective analysis of 425 children with epilepsy who had not had a seizure for at least 2 years (follow-up after withdrawal 1.6-12 years, mean 8 years). Factors closely related by multivariate analysis to relapse were neurologic abnormalities, mental retardation, seizure type (infantile spasms, absence seizures), and appearance or persistence of EEG abnormalities during the course of the illness and before discontinuation. When multivariate analysis was performed to evaluate outcome of patients with a first relapse (isolated vs. multiple relapses), the variables closely related to a poor prognosis were etiologic factors, first relapse characterized by more than one seizure in a 24-h period, seizure-free period less than 4 years, unchanged seizure type at first relapse, more than one AED for seizure control, and abnormal EEG before the first relapse. In itself, resumption of therapy did not influence outcome. At the study cutoff point, 88% of patients with relapse were again seizure-free. We conclude that AEDs can safely be discontinued if predictive factors are considered to individualize the risk of relapse for each patient.

We have tried to ascertain whether the increased visual evoked potential (VEP) amplitude found in adult migraineurs is present also in children with migraine. We investigated 43 children, 26 male and 17 female, with a mean age of 11.4 years, 24 with common and 19 with classic migraine, and compared them with a control group of 20 children, 11 male and 9 female, with a mean age of 9.7 years. Flash and pattern reversal VEPs were recorded in both groups, and the study was carried out in the pain-free interval between attacks. The children with migraine showed a significant (p less than 0.01) increase in VEP amplitude on flash stimulation but not on pattern reversal. There were no differences between classic and common migraine. The abnormal responsiveness of the visual system seems to be related to variations in light intensity rather than to spatial contrasts.

The cognitive deficit often associated with epilepsy is attributable to the presence and interaction of several factors but whether recurrent subclinical spike-wave discharges interfere with cognitive development is not yet clear. In the present study, the presence of subclinical discharges proved to be significantly associated with lower than average Full-Scale Intelligence Quotient (IQ), Verbal IQ and Performance IQ scores (Wechsler Intelligence Scale for Children) in comparison with patients not presenting EEG abnormalities during test. These findings confirm the adverse effect both of generalized and focal EEG epileptiform abnormalities, even if unaccompanied by overt seizures.