Discordant electroencephalogram epileptiform activity and hemispherectomy in children with refractory epilepsy and encephaloclastic lesions: a case series.

This is a case series of six children with unilateral cerebral palsy and hemispheric encephaloclastic lesions who were evaluated for epilepsy surgery. Seizure onset was in the neonatal period in three children, at 17 months in two, and at 5 years in one. Their ictal and interictal electroencephalogram (EEG) abnormalities showed paradoxical lateralization to the incorrect/'normal' hemisphere or showed bilateral abnormalities. After cautious discussion regarding the discordant electroclinical profile and implications for outcome, they proceeded to a functional hemispherectomy (between ages 4-11y) with good outcomes (at 1-10y follow-up). Their clinical details, EEG findings, electrocorticography, neuroimaging, and histology are reported. Possible surgical candidacy should be evaluated early in children with refractory epilepsy, even those with complex profiles and discordant data from the different investigations. Contralateral or bilateral EEG abnormalities should not preclude consideration of hemispherectomy in children with refractory epilepsy, hemiparesis, and uniclastic lesions.

Novel COL4A2 variant in a large pedigree: Consequences and dilemmas.

Pathogenic COL4A2 variants cause abnormalities in collagen production and can have serious implications for a range of organ systems, most notably the brain. Herein, we describe a large family of first-degree relatives affected by a novel heterozygous variant in COL4A2 (c.3490G.A). A wide disease spectrum is described, from asymptomatic to symptomatic, including 2 children with porencephaly and co-existing juvenile idiopathic polyarthritis. During a subsequent pregnancy, antenatal testing identified a positive fetus. In view of the literature, we review management and genetic counselling dilemmas.

Further refinement of COL4A1 and COL4A2 related cortical malformations.

Mutations in COL4A1 have been reported in schizencephaly and porencephaly combined with microbleeds or calcifications, often associated with ocular and renal abnormalities, myopathy, elevated creatine kinase levels and haemolytic anaemia. In this study, we aimed to clarify the phenotypic spectrum of COL4A1/A2 mutations in the context of cortical malformations that include schizencephaly, polymicrogyria and/or heterotopia. METHODS: We screened for COL4A1/A2 mutations in 9 patients with schizencephaly and/or polymicrogyria suspected to be caused by vascular disruption and leading to a cerebral haemorrhagic ischaemic event. These included 6 cases with asymmetrical or unilateral schizencephaly and/or polymicrogyria and 3 cases with bilateral schizencephaly. RESULTS: One de novo missense COL4A1 mutation (c.3715 G > A, p.(Gly1239Arg)) and two COL4A2 mutations were found, respectively in one familial case (c.4129G > A, p.(Gly1377Arg)) and one sporadic patient (c.1776+1G > A). In three other cases, COL4A1 variants of unknown significance were identified. None of our patients demonstrated neuromuscular or hematological anomalies. Brain malformations included a combination of schizencephaly, mainly asymmetrical, with porencephaly or ventriculomegaly (3/3 mutated patients). We did not observe microbleeds or microcalcifications in any of our cases, hence we do not believe that they represent a distinctive feature of COL4A1/A2 mutations. CONCLUSIONS: Our study further emphasizes the need to search for both COL4A1 and COL4A2 mutations in children presenting with uni- or bilateral polymicrogyria with schizencephaly, even in the absence of intracranial microbleeds, calcification or associated systemic features.

A case of tubulinopathy presenting with porencephaly caused by a novel missense mutation in the TUBA1A gene.

BACKGROUND: Tubulinopathies include a wide spectrum of disorders ranging from abnormal ocular movement to severe brain malformations, and typically present as diffuse agyria or perisylvian pachygyria with microcephaly, agenesis of the corpus callosum, and cerebellar hypoplasia. They are caused by the dysfunction of tubulins encoded by tubulin-related genes, and the TUBA1A gene encoding alpha-1A tubulin is most frequently responsible for this clinical entity. Porencephaly is relatively rare among patients with the TUBA1A mutations. Mild case of tubulinopathy associated with porencephaly caused by a novel TUBA1A mutation. CASE REPORT: The patient, a 10-month-old girl, presented with gross motor delay at 4 months of age and convulsions at 7 months of age. Brain magnetic resonance imaging showed porencephaly, occipital polymicrogyria, hypoplasia of the corpus callosum, volume loss of the white matter, dysgenesis of anterior limbs of internal capsules, non-separative basal ganglia, cerebellar hypoplasia, and dysplastic brainstem. We identified a novel de novo heterozygous missense mutation in the TUBA1A gene, c.381C > A (p.Asp127Glu), by whole-exome sequencing. DISCUSSION: Microtubules composed of tubulins regulate not only neuronal migration but also cell division or axon guidance. Accordingly, tubulinopathy affects the cortical lamination, brain size, callosal formation, and white matter as seen in the present case. In contrast to the previously reported cases, the present case showed milder cortical dysgenesis with a rare manifestation of porencephaly. The genotype-phenotype correlation is still unclear, and this study expands the phenotypic range of tubulinopathy.

MEG May Reveal Hidden Population of Spikes in Epilepsy With Porencephalic Cyst/Encephalomalacia.

Porencephalic cyst/encephalomalacia is often associated with intractable epilepsy. A limited number of studies reported magnetoencephalography's (MEG's) potential to help construct treatment strategy for epilepsies associated with porencephalic cyst/encephalomalacia. The authors present here simultaneous electroencephalography (EEG) and MEG findings in three adult patients with pediatric-onset epilepsy due to porencephalic cyst/encephalomalacia. There were two types of spikes: one type was detected by MEG only (EEG-/MEG+), and the other detected by both EEG and MEG (EEG+/MEG+). Both types were seen in all three cases. The EEG-/MEG+ spikes all formed tight clusters; in contrast, the majority of EEG+/MEG+ spikes formed loose clusters. These data suggest that MEG may be helpful to better identify spike populations in epilepsy patients with porencephalic cyst/encephalomalacia. If hidden spike populations were to be found by MEG, this information would affect the interpretation of patient's pathophysiology and planning of intracranial electrode placement.