Hemispherotomy in an infant with hemimegalencephaly and Ohtahara syndrome

We represent the case of a premature twin neonate born from uncomplicated pregnancy who developed seizures at the age of 24 h. Two-dimensional ultrasound and magnetic resonance imaging revealed left-sided hemimegalencephaly. Further extensive diagnostic evaluation revealed a diagnosis of Ohtahara syndrome. Resistance of the seizures to antiepileptic therapy led to hemispherotomy that was performed at the age of 10 months. Our patient is now a 4-year-old child, walking, eating without a nasogastric tube, still with right hemiparesis and lateral strabismus but without seizures.

Late adult-onset epilepsy in a patient with hemimegalencephaly

Hemimegalencephaly is a malformation of cortical development that normally manifests in childhood with seizures and cognitive impairment. We present a case of hemimegalencephaly in a 55-year-old developmentally-normal woman who developed focal impaired awareness seizures with bilateral tonic-clonic spread. Her interictal EEG showed left-sided multifocal spikes, and ictal EEG showed seizures starting in the left hemisphere. Imaging showed hemimegalencephaly. This case may represent the oldest age for a first seizure in a patient with hemimegalencephaly.

Virmid: accurate detection of somatic mutations with sample impurity inference

Detection of somatic variation using sequence from disease-control matched data sets is a critical first step. In many cases including cancer, however, it is hard to isolate pure disease tissue, and the impurity hinders accurate mutation analysis by disrupting overall allele frequencies. Here, we propose a new method, Virmid, that explicitly determines the level of impurity in the sample, and uses it for improved detection of somatic variation. Extensive tests on simulated and real sequencing data from breast cancer and hemimegalencephaly demonstrate the power of our model. A software implementation of our method is available at http://sourceforge.net/projects/virmid/.