Frontal lobe seizures.

BACKGROUND AND OBJECTIVE: Frontal lobe epilepsy is the second most common localization-related or focal epilepsy. Frontal lobe seizures are challenging to diagnose as the clinical manifestations are diverse due to the complexity and variability of the patterns of epileptic discharges, and the scalp electroencephalograph (EEG) can often be normal or misleading. This review focuses on the clinical and EEG features of seizures arising from the frontal lobe. REVIEW SUMMARY: The clinical manifestations in patients with frontal lobe epilepsy are varied. Frontal lobe seizures can be divided into perirolandic, supplementary sensorimotor area, dorsolateral, orbitofrontal, anterior frontopolar, opercular, and cingulate types. Seizures originating from the perirolandic and supplementary sensorimotor areas are clinically distinct, characterized by motor activity or asymmetric tonic posturing with preserved awareness. Seizures arising from dorsolateral, orbitofrontal, frontopolar, and cingulate areas are not as well characterized and have more variable clinical manifestations. Scalp EEG recording is sometimes helpful in localization but is usually normal or misleading in frontal lobe epilepsy. The treatment is similar to other localization-related or focal epilepsies. Medications are the first line of therapy, and surgery is considered for patients who fail to respond to medications. The surgical outcome in frontal lobe resections is less favorable than in anterior temporal lobectomies due to the challenge in locating the epileptogenic zone and the presence of functional areas (eloquent cortex) that can limit the resection. CONCLUSIONS: Frontal lobe seizures are characterized by diverse behavioral manifestations. Only a few well-described frontal lobe syndromes exist. The variety of clinical manifestations reflects both the varying sites of seizure origin and propagation routes that seizures may take. Although this review provides a framework for the understanding of these seizures, one should remain cautious in diagnosing seizure localization based on clinical or EEG description. Only a few patients have well-described syndromes and can be diagnosed with confidence. For most patients, new diagnostic methods and genetic testing may help improve our ability to diagnose and treat the conditions discussed in this study.

Seizure-related injury and death.

Epilepsy is associated with significantly increased morbidity and mortality from a variety of causes. Patients with epilepsy have approximately two to three times the risk of death from any cause compared with persons without epilepsy. Seizures may cause significant trauma, drowning, and accidental injury. Many of the deaths in persons with epilepsy are directly related to seizures, accidents and injuries arising from seizures, and the underlying condition resulting in seizures. This review focuses on recent data regarding seizure-related injury and mortality.

Progressive necrotizing myelopathy: part of the spectrum of neuromyelitis optica?

This case series reviews the clinical, radiographic and laboratory findings of five patients with progressive idiopathic myelopathy with evidence of cord necrosis who presented in our institution over a 5 year period ending in May 2005. Patients fulfilling the following criteria were included: (1) presentation with myelopathy without overt visual involvement at initial presentation; (2) demonstration with magnetic resonance imaging (MRI) of contiguously abnormal signal in the spinal cord spanning at least three vertebral segments without evidence of arteriovenous malformation or significant disk disease; (3) absence of systemic disease or neoplasm. All patients were women, identified themselves as African American and were older than 35 years. Pain was reported at initial presentation in four cases. The distinctive feature was a relapsing course with intervening variable improvement of function and progression to quadriplegia in less than 4 years. An increased IgG index and/or oligoclonal banding was detected in two patients. The leukocyte count in the cerebrospinal fluid (CSF) was elevated in all cases but in only one specimen did the count exceed 50 cells. None of the patients initially had clinical signs of an optic neuropathy but unilaterally prolonged visual evoked potentials were present in one individual who went on to developed optic neuritis 19 months after the first clinical presentation. Another patient developed optic neuritis 45 months after disease onset. Immunomodulatory and plasma exchange therapy were of some benefit at least early in the course but the disease progressed despite these interventions. Neuromyelitis optica (NMO)-IgG antibody, a serum or CSF marker described in individuals with classic NMO and optico-spinal multiple sclerosis (MS), was present in all cases. On the basis of shared clinical and imaging features in the cord, progressive necrotizing myelopathy observed in this case series exhibits key features of a limited form of NMO (Devic's disease) and opticospinal MS. The presence of NMO-IgG antibody marker suggests that progressive necrotizing myelopathy is part of a disease spectrum of which traditional NMO is a select presentation.

No influence of scopolamine hydrobromide on odor detection performance of rats.

Despite speculation that the muscarinic cholinergic antagonist, scopolamine, may influence the olfactory sensitivity of rats, there have been no definitive studies on this point to date. In this study, we examined the influence of a range of doses of scopolamine hydrobromine (namely, 0.10, 0.125, 0.15 and 0.20 mg/kg i.p.) on the odor detection performance of 15 adult male Long-Evans rats to ethyl acetate. Air-dilution olfactometry and a go/no-go operant signal detection task were employed. The drug conditions and a saline control were administered to each animal in an order counterbalanced by Latin squares, with 2 day intervals interspersed between tests. Scopolamine had no significant influence on odor detection performance per se, as measured by percent correct S+ and S- responses and a non-parametric signal detection measure of sensitivity. This is in contrast to the relatively large effects previously observed in the same test paradigm for such drugs as the D-1 agonist SKF 38393 and the D-2 agonist quinpirole. These data suggest that scopolamine has no meaningful influence on a well-practiced odor detection task.