Seizures in Children

Abstract

1. Philippe Major, MD* 2. Elizabeth A. Thiele, MD, PhD* 1. *Department of Neurology, Massachusetts General Hospital, Boston, Mass After completing this article, readers should be able to: 1. Formulate an appropriate diagnostic plan for a child who has seizures. 2. Discuss the management of epilepsy. The initial article on seizures in childhood (October 2007) focused on the diagnosis and classification of seizures in children. This second article reviews investigational tools and management. The evaluation of a child who has a seizure disorder must be tailored to the findings on history and physical examination. The electroencephalogram (EEG) is the primary electrophysiologic tool; brain neuroimaging is the primary modality for evaluating neuroanatomic and functional features. The EEG can help confirm the clinical diagnosis of epilepsy, classify the type of epilepsy, localize the epileptic focus, and help determine if treatment can be discontinued safely. In general, 21 electrodes placed on specific locations on the patient's scalp measure voltage fluctuations of superficial neurons in relation to time. Figure 1 shows the position and labeling of the scalp electrodes; Figures 2through ⇓⇓⇓6 show examples of typical EEG tracings. Generalized epileptic syndromes are characterized by discharges recorded simultaneously at each electrode; partial epilepsy syndromes show localized spikes or slowing in the epileptogenic region. Epilepsy is a clinical diagnosis that cannot be made on the basis of abnormal EEG findings. In fact, EEG abnormalities can be found in 5% of children who have no history of seizures. Figure 1. Scalp electrode positions for EEG. By convention, electrodes labeled with an even number are placed over the right hemisphere, and odd-numbered electrodes are placed over the left hemisphere. Fp=frontopolar, F=frontal, T=temporal, C=central, P=parietal, O=occipital, z=midline Figure 2. Normal EEG tracing showing a reactive posterior alpha (9-Hz) rhythm in an 8-year-old boy who has no history of seizures. The slow waves observed in the frontal areas are associated with eye movements. Figure 3. EEG tracing showing frequent independent left and right …