The role of perfusion CT in identifying stroke mimics in the emergency room: a case of status epilepticus presenting with perfusion CT alterations

Emergency medicine physicians are often faced with the challenging task of differentiating true acute ischemic strokes from stroke mimics. We present a case that was initially diagnosed as acute stroke. However, perfusion CT and EEG eventually led to the final diagnosis of status epilepticus. This case further asserts the role of CT perfusion in the evaluation of patients with stroke mimics in the emergency room setting

The Effect of High and Low Antiepileptic Drug Dosage on Simulated Driving Performance in Person’s with Seizures: A Pilot Study

Background: Prior studies examining driving performance have not examined the effects of antiepileptic drugs (AED’s) or their dosages in persons with epilepsy. AED’s are the primary form of treatment to control seizures, but they are shown to affect cognition, attention, and vision, all which may impair driving. The purpose of this study was to describe the characteristics of high and low AED dosages on simulated driving performance in persons with seizures. Method: Patients (N = 11; mean age 42.1 ± 6.3; 55% female; 100% Caucasian) were recruited from the Epilepsy Monitoring Unit and had their driving assessed on a simulator. Results: No differences emerged in total or specific types of driving errors between high and low AED dosages. However, high AED drug dosage was significantly associated with errors of lane maintenance (r = .67, p \u3c .05) and gap acceptance (r = .66, p \u3c .05). The findings suggest that higher AED dosages may adversely affect driving performance, irrespective of having a diagnosis of epilepsy, conversion disorder, or other medical conditions. Conclusion: Future studies with larger samples are required to examine whether AED dosage or seizure focus alone can impair driving performance in persons with and without seizures

Lateralization of mesial temporal lobe epilepsy with chronic ambulatory electrocorticography

OBJECTIVE: Patients with suspected mesial temporal lobe (MTL) epilepsy typically undergo inpatient video-electroencephalography (EEG) monitoring with scalp and/or intracranial electrodes for 1 to 2 weeks to localize and lateralize the seizure focus or foci. Chronic ambulatory electrocorticography (ECoG) in patients with MTL epilepsy may provide additional information about seizure lateralization. This analysis describes data obtained from chronic ambulatory ECoG in patients with suspected bilateral MTL epilepsy in order to assess the time required to determine the seizure lateralization and whether this information could influence treatment decisions. METHODS: Ambulatory ECoG was reviewed in patients with suspected bilateral MTL epilepsy who were among a larger cohort with intractable epilepsy participating in a randomized controlled trial of responsive neurostimulation. Subjects were implanted with bilateral MTL leads and a cranially implanted neurostimulator programmed to detect abnormal interictal and ictal ECoG activity. ECoG data stored by the neurostimulator were reviewed to determine the lateralization of electrographic seizures and the interval of time until independent bilateral MTL electrographic seizures were recorded. RESULTS: Eighty-two subjects were implanted with bilateral MTL leads and followed for 4.7 years on average (median 4.9 years). Independent bilateral MTL electrographic seizures were recorded in 84%. The average time to record bilateral electrographic seizures in the ambulatory setting was 41.6 days (median 13 days, range 0-376 days). Sixteen percent had only unilateral electrographic seizures after an average of 4.6 years of recording. SIGNIFICANCE: About one third of the subjects implanted with bilateral MTL electrodes required >1 month of chronic ambulatory ECoG before the first contralateral MTL electrographic seizure was recorded. Some patients with suspected bilateral MTL seizures had only unilateral electrographic seizures. Chronic ambulatory ECoG in patients with suspected bilateral MTL seizures provides data in a naturalistic setting, may complement data from inpatient video-EEG monitoring, and can contribute to treatment decisions

Homicide during postictal psychosis

Postictal psychosis is characterized by a fluctuating combination of thought disorder, auditory and visual hallucinations, delusions, paranoia, affective change, and aggression including violent behavior. We present a case of homicide following a cluster of seizures. The patient's history and postictal behavior were his consistent with postictal psychosis. Contributing factors resulting in homicide may have included increased seizure frequency associated with a change in his AED regimen seizure frequency. The AED change to levetiracetam may also have increased impulsiveness with diminished mood regulation following discontinuation of carbamazepine. There is evidence that he had a cluster of seizures immediately prior to the murder which may have resulted in the postictal disinhibition of frontal lobe inhibitory systems. This homicide and other violent behaviors associated with postictal psychosis may be avoided with earlier recognition and treatment

An Intrinsic Geometric Framework for Simultaneous Non-Rigid Registration and Segmentation of Surfaces

International audienceIn clinical applications where structural asymmetries between homologous shapes have been correlated with pathology, the questions of definition and quantification of 'asymmetry' arise naturally. When not only the degree but the position of deformity is thought relevant, asymmetry localization must also be addressed. Asymmetries between paired shapes can and have been formulated in the literature in terms of (nonrigid) diffeomorphisms between the shapes. For the infinity of such maps possible for a given pair, we define optimality as the minimization of total distortion, where 'distortion' is in turn defined as deviation from isometry.We thus propose a novel variational formulation for segmenting asymmetric regions from surface pairs based on the minimization of a functional of both the deformation map and the segmentation boundary, which controls gradient discontinuity of the map. This minimization is achieved via a quasi-simultaneous evolution of the map and curve. Our formulation is inherently intrinsic and parameterization-independent.We present examples using both synthetic data and pairs of left and right hippocampal structures, hippocampus malformation being linked with such neurological disorders as epilepsy and schizophrenia

Motor Impairments in Transient Ischemic Attack Increase the Odds of a Subsequent Stroke: A Meta-Analysis

Background and purposeTransient ischemic attack (TIA) increases the risk for a subsequent stroke. Typical symptoms include motor weakness, gait disturbance, and loss of coordination. The association between the presence of motor impairments during a TIA and the chances of a subsequent stroke has not been examined. In the current meta-analysis, we examine whether the odds of a stroke are greater in TIA individuals who experience motor impairments as compared with those who do not experience motor impairments.MethodsWe conducted a systematic search of electronic databases as well as manual searches of the reference lists of retrieved articles. The meta-analysis included studies that reported an odds ratio relating motor impairments to a subsequent stroke, or the number of individuals with or without motor impairments who experienced a subsequent stroke. We examined these studies using rigorous meta-analysis techniques including random effects model, forest and funnel plots, I2, publication bias, and fail-safe analysis.ResultsTwenty-four studies with 15,129 participants from North America, Australia, Asia, and Europe qualified for inclusion. An odds ratio of 2.11 (95% CI, 1.67–2.65, p = 0.000) suggested that the chances of a subsequent stroke are increased by twofolds in individuals who experience motor impairments during a TIA compared with those individuals who have no motor impairments.ConclusionThe presence of motor impairments during TIA is a significantly high-risk clinical characteristic for a subsequent stroke. The current evidence for motor impairments following TIA relies exclusively on the clinical reports of unilateral motor weakness. A comprehensive examination of motor impairments in TIA will enhance TIA prognosis and restoration of residual motor impairments

Intracranial hypotension masquerading as nonconvulsive status epilepticus: report of 3 cases

Intracranial hypotension (IH) has been a known entity in neurocritical care since 1938. Even though many cases are spontaneous, the incidence of intracranial hypotension in the neurocritical care setting is increasing by virtue of the increased number of neurosurgical interventions. Whether spontaneous or secondary in etiology, diagnosis of IH usually requires the presence of orthostatic symptoms, including headaches and nausea with low opening CSF pressure. However, typical clinical features in the appropriate clinical context and imaging, even with normal CSF pressure, can indicate IH. In the neurocritical care setting, challenges for accurate semiology include altered sensorium and reduced levels of responsiveness for which many etiologies may exist, including metabolic dysfunction, traumatic brain injury, IH, or nonconvulsive status epilepticus (NCSE). The authors describe 3 patients whose clinical picture and electroencephalography (EEG) findings initially suggested NCSE but who did not respond to treatment with antiepileptic drugs alone. Neuroimaging suggested IH, and subsequent treatment of IH successfully improved the patient\u27s clinical status. To the authors\u27 knowledge this paper is the first in the literature that reports a correlation of IH with electrographic findings similar to NCSE as cause and effect. The authors\u27 hypothesis is that thalamocortical dysfunction causes EEG findings that appear to be similar to those in NCSE but that these conditions do not coexist. The EEG activity is not epileptogenic, and IH results in blocking network pathways producing thalamocortical dysfunction. The authors discuss the hypothesis and pathophysiology of these epileptiform changes in relation to IH