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Introduction: To determine the occurrence of neuroradiological abnormalities and to perform genotype-phenotype correlations in severe myoclonic epilepsy of infancy (SMEI, Dravet syndrome)., Patients and Methods: Alpha-subunit type A of voltage-gated sodium channel (SCN1A) mutational screening was performed by denaturing high-performance liquid chromatography (DHPLC) and multiplex ligation probe amplification (MLPA). MRI inclusion criteria were: last examination obtained after the age of 4 years on 1.5-T systems; hippocampal cuts acquired perpendicular to the long axis of the hippocampus; qualitative assessment was performed on T(1)-weighted, T(2)-weighted, proton density, and 1-3 mm thick coronal FLAIR images., Results: We collected 58 SMEI patients in whom last MRI was performed at or later than 4 years of age. SCN1A mutations occurred in 35 (60%) cases. Thirteen (22.4%) out of 58 patients showed abnormal MRIs. Eight patients showed cortical brain atrophy of which 3 associated to ventricles abnormalities, 1 to cerebellar atrophy, 1 to white matter hyperintensity; 3 patients had ventricles enlargement only; 1 patient showed hippocampal sclerosis (HS); 1 had focal cortical dysplasia. Genotype-phenotype analysis indicated that abnormal MRIs occurred more frequently in patients without SCN1A mutations (9/23; 39.1%) compared to those carrying SCN1A mutations (4/35; 11.4%) (p=0.02)., Conclusion: Different brain abnormalities may occur in SMEI. Only one case with HS was observed; thus, our study does not support the association between prolonged febrile seizures and HS in SMEI. Abnormal MRIs were significantly more frequent in patients without SCN1A mutations. Prospective MRI studies will assess the etiological role of the changes observed in these patients.

Mental retardation, facial dysmorphisms, seizures, and brain abnormalities are features of 6q terminal deletions. We have ascertained five patients with 6q subtelomere deletions (four de novo, one as a result of an unbalanced translocation) and determined the size of the deletion ranging from 3 to 13 Mb. Our patients showed a recognizable phenotype including mental retardation, characteristic facial appearance, and a distinctive clinico-neuroradiological picture. Focal epilepsy with consistent electroencephalographic features and with certain brain anomalies on neuroimaging studies should suggest 6q terminal deletion. The awareness of the distinctive clinical picture will help in the diagnosis of this chromosomal abnormality.

A previously unreported epileptic condition characterised by onset before 6 months of age, nearly continuous electroencephalographic seizures involving multiple independent areas originating in both hemispheres, no identifiable cause, and poor outcome has been described by Coppola et al. We report three cases presenting the same clinical and EEG pictures. They show a peculiar epileptic condition unlike the other early epileptogenic encephalopathies, so they may represent a new infantile epileptic syndrome.

Ten cases of epilepsy with continuous spike waves in slow-wave sleep (CSWS) were evaluated using single photon emission computed tomography (SPECT); in eight patients the EEG paroxysmal abnormalities showed a predominant localization. SPECT carried out using 99mTc-HMPAO allows study of cerebral blood flow (CBF); the examination was performed during phases of drowsiness and the results compared to the EEG data. In four cases SPECT revealed areas of low CBF in sites corresponding to those of the prevalent EEG discharges; in two cases the areas of hypoperfusion did not correspond to those indicated by the EEG; lastly, in four cases SPECT results were negative. The areas of hypoperfusion were predominantly located in the frontal, temporal, and parietal regions. Furthermore, the percentage of positive SPECT results was significantly higher (five cases out of six) in the group in which the CSWS phase was prolonged for at least 1 year, compared to the group in which this phase lasted less than 1 year. Thus, in this type of epilepsy, SPECT reveals focal cortical areas of decreased CBF which correlated generally to the predominant sites of EEG abnormalities. A longer duration of the CSWS phase seems to be associated with a more significant cortical disorder, documented by the presence of areas of hypoperfusion.

We have observed in two different families two pairs of male siblings born from normal, non-consanguineous parents having the same syndrome, characterized by severe cerebral white matter hypoplasia, agenesis or extreme hypoplasia of the corpus callosum, mental retardation, failure to thrive and minor midline facial abnormalities. This seems to be a previously unreported genetic syndrome.

Chronic "neurogenic" hypernatremia is the consequence of defective thirst mechanism either alone or in combination with impaired osmoregulation of ADH release. Both the specific receptors and the structures involved in hormonal secretion are localised in the hypothalamic area. "Neurogenic" hypernatremia can be secondary to a hypothalamic lesion of different type (neoplastic, vascular, malformative) or rarely it can be idiopathic. We present three cases: two females 4 and 5 months old, affected by cerebral malformations involving midline structures of the brain (III ventricule, corpus callosum etc.) and a male 4 years old with a idiopathic form. We discuss the relationship between the origin of the cerebral malformations and the ontogeny of the structures involved in the control of the osmolarity. Moreover we have observed that the hypernatremia in associated with hyperlipemia: the pathogenetic hypothesis explaining this abnormality are discussed.

Neurological and psychic side effects of anticonvulsivant drugs in pediatric age are separately considered. Neurological side effects are classified according to different ages: in the neonatal period sedation is preeminent, later psychomotor deterioration or cerebellar and/or extrapyramidal signs may occur. Less frequently antiepileptic drugs are responsible of worsening of seizures up to a toxic encephalopathy. Psychic side effects are more variable and unpredicatable. The same drugs can cause both psychomotor excitement or psychic slowness. In a few instances psychotic syndromes can be observed. Very important are chronic side effects on intellectual activities, especially in children. Finally some factors which can affect the interpretation of the side effects have to be considered: pharmacokinetic data individual reactivity, methodology of evaluation of clinical symptoms, especially psychic ones.