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1.  MEF2C Haploinsufficiency features consistent hyperkinesis, variable epilepsy, and has a role in dorsal and ventral neuronal developmental pathways 
Neurogenetics  2013;14(2):99-111.
MEF2C haploinsufficiency syndrome is an emerging neurodevelopmental disorder associated with intellectual disability, autistic features, epilepsy, and abnormal movements. We report 16 new patients with MEF2C haploinsufficiency, including the oldest reported patient with MEF2C deletion at 5q14.3. We detail the neurobehavioral phenotype, epilepsy, and abnormal movements, and compare our subjects with those previously reported in the literature. We also investigate Mef2c expression in the developing mouse forebrain. A spectrum of neurofunctional deficits emerges, with hyperkinesis a consistent finding. Epilepsy varied from absent to severe, and included intractable myoclonic seizures and infantile spasms. Subjects with partial MEF2C deletion were statistically less likely to have epilepsy. Finally, we confirm that Mef2c is present both in dorsal primary neuroblasts and ventral gamma-aminobutyric acid(GABA)ergic interneurons in the forebrain of the developing mouse. Given interactions with several key neurodevelopmental genes such as ARX, FMR1, MECP2, and TBR1, it appears that MEF2C plays a role in several developmental stages of both dorsal and ventral neuronal cell types.
doi:10.1007/s10048-013-0356-y
PMCID: PMC3773516  PMID: 23389741
MEF2C haploinsufficiency; Intellectual disability; Autism; Infant-onset myoclonic epilepsy; Infantile spasms; Hyperkinesis; Deletion 5q14.3
2.  Focal cortical dysplasia is more common in boys than girls 
Epilepsy & behavior : E&B  2013;27(1):121-123.
Genetics and environment likely contribute to the development of medically intractable epilepsy, however, in most patients the specific combination of etiologies remains unknown. Here we undertook a multicenter retrospective cohort study of sex distribution in pediatric patients undergoing epilepsy surgery, and carried out a secondary analysis of the same population subdivided by histopathologic diagnosis. In the multicenter cohort of intractable epilepsy patients undergoing surgery regardless of etiology (n=206), 63% were boys, which is significantly more boys than expected for the general population (Fisher exact two-tailed p=0.017). Subgroup analysis found that of the 90 patients with a histopathologic diagnosis of focal cortical dysplasia, 72% were boys, giving an odds ratio (OR) of 2.5 (95% CI, 1.34 to 4.62) for male sex. None of the other etiologies had a male sex predominance. Future studies could examine the biological relevance and potential genetic and pathophysiological mechanisms of this observation.
doi:10.1016/j.yebeh.2012.12.035
PMCID: PMC3930197  PMID: 23416281
focal cortical dysplasia; pediatric epilepsy; epilepsy surgery; gender; sex
3.  Leaving tissue associated with infrequent intracranial EEG seizure onsets is compatible with post-operative seizure freedom 
Journal of pediatric epilepsy  2012;1(4):211-219.
Identify seizure onset electrodes that need to be resected for seizure freedom in children undergoing intracranial electroencephalography recording for treatment of medically refractory epilepsy. All children undergoing intracranial electroencephalography subdural grid electrode placement at the Children’s Hospital of Philadelphia from 2002-2008 were asked to enroll. We utilized intraoperative pictures to determine the location of the electrodes and define the resection cavity. A total of 15 patients had surgical fields that allowed for complete identification of the electrodes over the area of resection. Eight of 15 patients were seizure free after a follow up of 1.7 to 8 yr. Only one seizure-free patient had complete resection of all seizure onset associated tissue. Seizure free patients had resection of 64.1% of the seizure onset electrode associated tissue, compared to 35.2% in the not seizure free patients (p=0.05). Resection of tissue associated with infrequent seizure onsets did not appear to be important for seizure freedom. Resecting ≥ 90% of the electrodes from the predominant seizure contacts predicted post-operative seizure freedom (p=0.007). The best predictor of seizure freedom was resecting ≥ 90% of tissue involved in majority of a patient’s seizures. Resection of tissue under infrequent seizure onset electrodes was not necessary for seizure freedom.
doi:10.3233/PEP-12033
PMCID: PMC3930198  PMID: 24563805
Epilepsy; epilepsy surgery; cortical dysplasia; neocortical epilepsy; intracranial electroencephalography
4.  Interictal EEG spikes identify the region of seizure onset in some, but not all pediatric epilepsy patients 
Epilepsia  2009;51(4):592-601.
Purpose
The role of sharps and spikes, interictal epileptiform discharges (IEDs), in guiding epilepsy surgery in children remains controversial, particularly with intracranial EEG (IEEG). While ictal recording is the mainstay of localizing epileptic networks for surgical resection, current practice dictates removing regions generating frequent IEDs if they are near the ictal onset zone. Indeed, past studies suggest an inconsistent relationship between IED and seizure onset location, though these studies were based upon relatively short EEG epochs.
Methods
We employ a previously validated, computerized spike detector, to measure and localize IED activity over prolonged, representative segments of IEEG recorded from 19 children with intractable, mostly extra temporal lobe epilepsy. Approximately 8 hours of IEEG, randomly selected thirty-minute segments of continuous interictal IEEG per patient were analyzed over all intracranial electrode contacts.
Results
When spike frequency was averaged over the 16-time segments, electrodes with the highest mean spike frequency were found to be within the seizure onset region in 11 of 19 patients. There was significant variability between individual 30-minute segments in these patients, indicating that large statistical samples of interictal activity were required for improved localization. Low voltage fast EEG at seizure onset was the only clinical factor predicting IED localization to the seizure onset region.
Conclusions
Our data suggest that automated IED detection over multiple representative samples of IEEG may be of utility in planning epilepsy surgery for children with intractable epilepsy. Further research is required to better determine which patients may benefit from this technique a priori.
doi:10.1111/j.1528-1167.2009.02306.x
PMCID: PMC2907216  PMID: 19780794
Spike density; intracranial EEG; Seizure onset; Pediatric Epilepsy

Results 1-4 (4)