Charles Akos Szabo

Hippocampal volumetry in children 6 years or younger: assessment of children with and without complex febrile seizures

PURPOSE To study the relationship of complex febrile seizures (CFS) in the evolution of mesial temporal sclerosis. METHODS We studied five children 22-68 (mean 44) months old with MRI volumetry 2 days-46 months after their first CFS, and compared total hippocampal volumes and right to left hippocampal volume ratios to those of 11 controls, 15-83 (mean 55) months old, who had MRI for complaints which turned out to be neurologically insignificant. RESULTS In control children, total hippocampal volumes increased linearly with age, while right to left hippocampal volume ratios tended to decrease with age. In children with CFS total hippocampal volumes tended to be smaller than in controls. Right to left ratios were greater than 1 in all five children with CFS compared to seven of 11 controls. Hippocampal asymmetry was noted in only one child, with the right to left volume ratio exceeding two standard deviations from the control mean. The MRI of this child also demonstrated a subarachnoid cyst in the left frontocentral region, ipsilateral to the smaller hippocampus. Visual inspection of the remaining patients revealed no definite structural cortical abnormalities. None of the children developed subsequent afebrile seizures during the brief follow-up period. CONCLUSIONS Hippocampal volumetry in controls revealed a linear increase in total hippocampal volumes and a statistically nonsignificant trend toward reduced right larger than left hippocampal ratios between 17 and 83 months old. The tendency for smaller total hippocampal volumes and larger right to left hippocampal volume ratios in children with CFS compared to controls could suggest a developmental abnormality, injury during CFS, or be age-related. The significant hippocampal asymmetry in a single child with CFS suggests that age may not be a factor in every case. Further studies are needed to collect control data in young children as well as prospectively follow children with CFS with serial imaging to better understand the relationship between CFS and the evolution of hippocampal atrophy.

Electromyography-based seizure detector: Preliminary results comparing a generalized tonic-clonic seizure detection algorithm to video-EEG recordings

Automatic detection of generalized tonic–clonic seizures (GTCS) will facilitate patient monitoring and early intervention to prevent comorbidities, recurrent seizures, or death. Brain Sentinel (San Antonio, Texas, USA) developed a seizure‐detection algorithm evaluating surface electromyography (sEMG) signals during GTCS. This study aims to validate the seizure‐detection algorithm using inpatient video–electroencephalography (EEG) monitoring.

Proposal: Different types of alteration and loss of consciousness in epilepsy

There are at least five types of alterations of consciousness that occur during epileptic seizures: auras with illusions or hallucinations, dyscognitive seizures, epileptic delirium, dialeptic seizures, and epileptic coma. Each of these types of alterations of consciousness has a specific semiology and a distinct pathophysiologic mechanism. In this proposal we emphasize the need to clearly define each of these alterations/loss of consciousness and to apply this terminology in semiologic descriptions and classifications of epileptic seizures. The proposal is a consensus opinion of experienced epileptologists, and it is hoped that it will lead to systematic studies that will allow a scientific characterization of the different types of alterations/loss of consciousness described in this article.

Cortical sulcal areas in baboons (Papio hamadryas spp.) with generalized interictal epileptic discharges on scalp EEG

Brain MRI studies in people with idiopathic generalized epilepsies demonstrate regional morphometric differences, though variable in magnitude and location. As the baboon provides an excellent electroclinical and neuroimaging model for photosensitive generalized epilepsy in humans, this study evaluated MRI volumetric and morphometric differences between baboons with interictal epileptic discharges (IEDs) on scalp EEG and baboons with normal EEG studies. Seventy-seven baboons underwent high-resolution brain MRI and scalp EEG studies. The scans were acquired using an 8-channel primate head coil (Siemens TRIO 3T scanner, Erlangen, Germany). After spatial normalization, sulcal measurements were obtained by object-based-morphology methods. One-hour scalp EEG studies were performed in animals sedated with ketamine. Thirty-eight (22F/16M) baboons had normal EEGs (IED-), while 39 (22F/17M) had generalized IEDs (IED+). The two groups were compared for age, total brain volume, and sulcal areas (Hotellings Trace) as well as between-subjects comparison of 11 individual sulcal areas (averaged between left and right hemispheres). There were no differences between IED- and IED+ groups with respect to age or total brain (gray or white matter) volume, and multivariate tests demonstrated a marginally significant decrease of sulcal areas in IED+ baboons (p=0.075). Tests of between-subjects effects showed statistically significant decreases in the intraparietal (p=0.002), central (p=0.03) and cingulate sulci (p=0.02), and marginal decreases involving the lunate (p=0.07) and superior temporal sulci (p=0.08). Differences in sulcal areas in IED+ baboons may reflect global developmental abnormalities, while decreases of areas of specific sulci reflect anatomical markers for potential generators or cortical nodes of the networks underlying spontaneous seizures and photosensitivity in the baboon.

Functional Hemispherectomy for Refractory Status Epilepticus in 2 Adults.

BACKGROUND Status epilepticus (SE) is a medical emergency, as deleterious long-term effects are well known. Medically induced burst suppression is often required if first-line and second-line treatments fail. Surgical intervention can be considered in some patients after prolonged treatment failure of medically induced coma. Multiple surgical options for terminating SE have been demonstrated in the literature, with only 2 reports including hemispherectomy in adults. CASE DESCRIPTION We present 2 cases of adults with refractory SE who failed more conservative medical/surgical treatment but responded to functional hemispherectomy. Pertinent electroencephalography and imaging findings are discussed. In addition, all previously published pediatric and adult cases are briefly reviewed. CONCLUSIONS Functional hemispherectomy can be considered in patients, including adults, with super-refractory SE and diffuse hemispheric onset. We report acceptable outcomes and quality of life in our 2 patients.

Subdural electrode recording of generalized photoepileptic responses

We evaluated the spatiotemporal distribution of photic driving (PDR), photoparoxysmal (PPR), and photoconvulsive (PCR) responses recorded by intracranial electrodes (ic-EEG) in a patient with generalized photosensitivity and right frontal lobe cortical dysplasia. Intermittent light stimulation (ILS) was performed thirteen times in nine days. Cortical responses to ILS recorded by ic-EEG were reviewed and classified as PDRs, PPRs, and PCRs. Photic driving responses were restricted to the occipital lobe at ILS frequencies below 9 Hz, spreading to the parietal and central regions at > 9 Hz. Photoparoxysmal responses commonly presented as focal, medial occipital, and parietal interictal epileptic discharges (IEDs), the latter propagating to the sensorimotor cortices. Generalized IEDs were also generated in the setting of PPRs. Photoconvulsive responses, characterized by repetitive bilateral upper extremity myoclonus sustained until the end of the stimulus, were associated with propagation of the medial parieto-occipital discharge to the primary sensorimotor and supplementary area cortices, while generalized myoclonic seizures were associated with a generalized spike-and-wave discharge with an interhemispheric posterior cingulate onset sparing the sensorimotor cortices. Both types of PCR could occur during the same stimulus. Regardless of the pathway, PCRs only occurred when PDRs involved the parietal cortices. While there may be more than one pathway underlying PCRs, parietal lobe association cortices appear to be critical to their generation.

Baboon Model of Genetic Generalized Epilepsy

Abstract The epileptic baboon, once studied because of its photosensitivity, has regained importance as a model for human genetic generalized epilepsy (GGE). Because of its electroclinical presentation, natural history, and response to antiepileptic medications, the genetic epilepsy closely resembles juvenile myoclonic epilepsy (JME). By combining intracranial EEG, structural, and functional MRI, it is evident that the occipital lobe plays a more central role in the baboon model of epilepsy, not only by mediating the photoepileptic response, but as a generator of ictal and interictal epileptic discharges. In contrast to earlier hypotheses suggesting that GGE in baboons and humans is due to an abnormal frontothalamic network, changes in cortical structure, whether developmental or seizure-induced, and in functional connectivity, indicate a more diffuse, multilobar disease. In this chapter, we will review EEG, neuroimaging findings, and histopathology in the epileptic baboon, exploring new directions of research into epileptogenesis, behavioral complications, and mortality associated with epilepsy, as well as novel therapies for GGE.

Complementary/alternative medicine for epilepsy

Epilepsy is a condition of recurrent seizures that are not caused by some other medical condition. Over 1.5 million people in the United States have been diagnosed with epilepsy, with about 150,000 new diagnoses each year. Antiepileptic drugs (AED) are the most common therapy used to treat epilepsy. There are a number of AED. The one chosen by the physician for a particular patient is based on several factors. These include the type of epilepsy the patient has, how likely the medicine is to work for that patient, and the side effects the medication may cause. Another thing to keep in mind is that many other medications, prescription and over the counter, may interfere with how well AED work. They may increase or decrease the amount of AED in the blood and brain, which in turn can lead to more seizures or side effects. More information about epilepsy can be found on the next page. In this issue of Neurology , investigators study the use of complementary or alternative therapies (CAM) by patients with epilepsy. “Complementary” and “alternative” are medications that are available over the counter without a prescription. They are not covered by medical insurance. Many have not been tested in scientific studies for how well they work or how safe they are. One goal of this study was to find out how often people with epilepsy use CAM. Other goals were to find out whether physicians knew whether their patients were using CAM and whether physicians even recognized more commonly used CAM. This study also gathered information about the effects of CAM use on seizure control and quality of life in patients with epilepsy. A 40-question survey was mailed to 3,100 …