The withdrawal of antiepileptic medication

Discontinuation of anti-epileptic drugs in patients who have been seizure-free for several years is an important decision due to their toxicity, the long-term use of these drugs may have adverse effects on systemic and/or neurologic functions. The point is how to predict from among the patients those who will achieve remission, and when, and those who will continue to have recurrent seizures despite all treatment. To achieve this goal an index to predict the recurrence risk was developed. Therapy must be reduced slowly and, on polytherapy, only one drug at a time.     

Ambulatory monitoring of A/EEG in the preoperative assessment of partial epilepsy

INTRODUCTION: Electroencephalography, together with new neuroimaging techniques is still the main diagnostic tool for pre-operative assessment of epilepsy. The electrical episodes, both ictal and intercritical, are random paroxystic phenomena with regard to presentation, so the conventional EEG is sometimes of limited value. Therefore, in recent years, long duration EEG monitoring techniques have been favoured, with or without simultaneous recording of clinical behaviour, permitting recording for an indefinite period. Amongst these techniques, monitoring using cassette recording (A/EEG) if of specific interest since it permits the study of outpatients. OBJECTIVE: The main aim of surgical treatment of epilepsy is to abolish or reduce the number of crises. Therefore it is essential to localize the epileptogenic area as precisely as possible. The A/EEG has made a major contribution to the procedure of pre-operative assessment because of the considerable information it gives regarding the recording and character of the crises. MATERIAL AND METHODS: During the past three years, preoperative assessment has been carried out in our hospital on 44 patients with drug-resistant partial epilepsy. A total of 103 long duration cassette recordings (A/EEG) were done. Of these, 58 were done with surface electrodes and individualized set-up depending on the EEG findings, 8 with semi-invasive (sphenoid) electrodes, and 37 recordings used implanted sub-dural electrode strips. RESULTS: Combined study of the results obtained with these techniques permitted localization of the lesive-epileptogenic complex in 42 of these patients. We present the results obtained and conclude that A/EEG monitoring is useful in the pre-operative assessment of epilepsy.     

Is partial epilepsy progressive? Ten-year follow-up of EEG and neuropsychological changes in adults with partial seizures

PURPOSE: This study was undertaken to determine what changes, if any, occur in the electroencephalogram (EEG) and in neuropsychological test findings of adults with medically intractable complex partial epilepsy over a 10-year period. METHODS: We studied 35 adults, with a mean age of 32 years (range, 16-59 years) at time of initial testing. We compared the distribution of epileptiform patterns documented on the initial pair of waking and sleeping EEGs to those observed on another pair obtained 10 years later. During this same 10-year period, we also examined changes in the Wechsler Adult Intelligence Scale (WAIS) and on the tests from the Neuropsychological Battery for Epilepsy. RESULTS: The EEGs of 28 (80%) of patients at the tenth year were identical to those seen initially. Five (14%) of patients demonstrated EEGs after 10 years with either no discharges or only unilateral discharges, where bilateral discharges were seen a decade earlier. Only two (6%) of patients had EEGs at the tenth year that showed bilateral discharges where only unilateral discharges were seen originally. We found no general change in intelligence or neuropsychological functioning after 10 years, although a few subtle losses were noted on several neuropsychological measures. CONCLUSIONS: For most adults with medically intractable complex partial epilepsy, the EEG and neuropsychological test scores remain reasonably stable over a decade.     

Etiology in complex partial epilepsy. II. Correlation between EEG topography and neuroimaging

Neuro-imaging studies (NI) in patients with complex partial seizures (CPC) demonstrate the epileptogenicity of a more or less localized underlying lesion. Correlation with the topography of the EEG focus permits affirmation of the origin. We analyze anomalies on NI and on the EEG of 151 patients with CPC. The EEG was abnormal in 128 and showed a unilateral epileptic focus in 117. NI was focal and unilateral in 72 of the 102 abnormal cases. Topographic correlation was 78.5%. This close correlation in our series makes us consider the localized lesions to be the probable aetiological factor.     

Preoperative EEG in medically intractable epilepsy

The aim of the preoperative neurophysiological investigations is to identify the primary epileptogenic focus and its relation to functional cortical areas. The investigations include interictal and ictal extracranial (scalp) electroencephalography (EEG) and invasive methods (depth, subdural, foramen ovale electrodes and peroperative electrocorticography). If an epileptic focus is located in the anterior part of the temporal lobe by the use of scalp EEG, this is normally regarded as sufficient for an anterior lobectomy. However, because of poor spatial resolution by scalp EEG, it is difficult to separate mesial from lateral foci, identify the exact extent of posterior temporal or extra-temporal foci, identify the primary focus in patients with bilateral abnormalities and identify cases with minor scalp EEG-changes. As invasive EEG shows higher spatial resolution and gives an opportunity to evaluate functional areas, invasive EEG has significant advantages in these patients. Use of invasive EEG bears a slightly increased risk and discomfort to the patient, but is necessary in the presurgical evaluation of some patients suffering from medically intractable epilepsy.     

Spectral characteristics of sleep EEG in chronic insomnia

To determine whether the spectral characteristics of the sleep electroencephalogram (EEG) of insomniacs differ from that of healthy subjects, we compared in each of the first four non-rapid eye movement (NREM) and rapid eye movement (REM) episodes: (a) the time courses of absolute power, averaged over the subjects in each group, for the delta, theta, alpha, sigma and beta frequency bands; (b) the relationship between these time courses; and (c) the overnight trend of integrated power in each frequency band. The results show that NREM power, for all frequencies below the beta range, has slower rise rates and reaches lower levels in the insomniac group, whereas beta power is significantly increased. In REM, insomniacs show lower levels in the delta and theta bands, whereas power in the faster frequency bands is significantly increased. Thus, the pathophysiology of insomnia is characterized not only by the generally acknowledged slow wave deficiency, but also by an excessive hyperarousal of the central nervous system throughout the night, affecting both REM and NREM sleep. This hyperarousal is interpreted in terms of the neuronal group theory of sleep which provides a possible explanation for the discrepancies observed between subjective impressions and objective measures of sleep. Also, it is suggested that the progressive hyperpolarization of the thalamocortical neurons as sleep deepens is slower in the patient population and that this may explain the observed slow wave deficiency. The homeostatic control of slow wave activity, on the other hand, would appear to be intact in the patient population.     

Benign partial epilepsy with affective symptoms: hyperkinetic behavior during interictal periods

We report a 4-year-old boy with benign partial epilepsy (BPE) with affective symptoms associated with hyperkinetic behavior during interictal periods. He had had hypermobility and restlessness since about age 3. At 4 years, 6 months, he developed episodes consisting of an expression of terror without complete loss of consciousness. Although we first suspected an acute psychic problem, the ictal EEG was abnormal. After carbamazepine (CBZ) therapy, the frequency of the attacks decreased dramatically and the hyperkinetic behavior gradually diminished.     

First-episode schizophrenia. Early intervention and medication discontinuation in the context of course and treatment

BACKGROUND: The concept that early intervention with antipsychotic medications improves the long-term course of schizophrenia is discussed. METHOD: This report reviews the literature concerning early intervention with antipsychotic medications for people with first episodes, and how it affects long-term morbidity. It also studies the effects of discontinuing antipsychotic medications on relapse for people with first episodes. RESULTS: Early intervention with antipsychotic medications appears to decrease the long-term morbidity of schizophrenia. CONCLUSIONS: Early intervention with antipsychotic medications should be encouraged for people experiencing their first episode of schizophrenia. This report proposes that studying the various phases of subject response to treatment can be helpful in elucidating when antipsychotic medications should be tapered or withdrawn.     

Antiepileptic drug-related cognitive complaints in seizure-free children with epilepsy before and after drug discontinuation

The cognitive complaints reported by children and their parents, as subjectively associated with antiepileptic drug (AED) treatment, were evaluated in seizure-free children before and after drug discontinuation. The aim of the design was to isolate the cognitive side effects of AEDs from other factors, such as the effect of seizures. Our inventory explored the following areas: "alertness," "concentration," "activation/ tiredness," "memory," "drowsiness," "depression," "aggressiveness," and "hyperactivity," using a 5-point Likert scaling procedure. One hundred two eligible patients were selected, each matched with a healthy control and assessed when still on antiepileptic medication. All children were seizure free for at least 1 year. The medication was then discontinued gradually over a 3-month period. Four months after the children were completely medication free, a second assessment was carried out, but only in the 83 children who remained seizure free and in their matched controls. The results of the reports made by the children themselves did not show differences with the matched controls, and only showed improvement after drug discontinuation for complaints about "tiredness." Parents of the children with epilepsy reported significant improvement in all areas related to "alertness and activation" after discontinuation of the drugs. The finding that only a limited number of children have cognitive complaints, both when still on AEDs and after discontinuation, may be in line with the reports that the major factor contributing to quality of life is whether patients are seizure free or still have seizures. All patients in this study were seizure free for a period >1 year, which may have caused the favorable pattern of response in our patient group.     

Familial partial epilepsy with variable foci: a new partial epilepsy syndrome with suggestion of linkage to chromosome 2

Traditional T2-based imaging techniques are geared toward imaging long-T2 species. Traditional techniques are, therefore, not optimal in clinical situations where the information of interest lies in the short-T2 species. T2-selective RF excitation (TELEX) is a technique for obtaining a T2-based contrast that highlights short-T2 values while suppressing long-T2 values-opposite to traditional T2 contrast. Previously, TELEX has been demonstrated qualitatively to highlight only very short-T2 values (T2 approximately 0.001 s). When applied to longer T2 values (T2 > or = 0.01 s), TELEX becomes sensitive to deltaB0 non-uniformities. This restricts its application to problems in which the T2 of interest is very short. In this study, TELEX is characterized quantitatively. Furthermore, a bandwidth broadening scheme is developed that reduces the deltaB0 sensitivity of TELEX. This permits the technique to be applied to longer T2 values. The capabilities and limitations of a practical implementation of TELEX are discussed.     

Grouped crises and status epilepticus in complex partial epilepsy

INTRODUCTION: In complex partial crises (CPC) some characteristics of the way in which they occur may be helpful in localizing the focus of origin in the cerebral cortex. Thus, the appearance of any kind of status epilepticus will not predominate depending on the origin of the epileptic focus, but the complex partial state will be rare when the origin is temporal and more frequent when the origin is frontal. The appearance of CPC in a cluster form is, on the other hand, characteristic of crises originating in the frontal lobe. MATERIAL AND METHODS: We review the clinical history of 151 epileptics with CPC, evaluating the way in which the crises appear, together with other clinical data. We define the start of the crisis in a specific lobe, when this was the site of maximum voltage of the epileptic anomaly or of maximum phase opposition. RESULTS: 10% of the patients showed grouping of their CPC; in the remainder the appearance was isolated, 15% showed status epilepticus at some point in their illness. We found a statistical difference when relating this to the anomalous topography of the EEG; between 15% and 42% more patients with status epilepticus were counted when the topography of the anomaly in the EEG was extratemporal. There was also between 37.2% and 76.4% more patients with cluster crises in the cases with an extratemporal focus.     

Psychopathology in pediatric complex partial and primary generalized epilepsy

Structured psychiatric interviews were administered to 60 children with complex partial seizure disorder (CPS), 40 children with primary generalized epilepsy with absences (PGE), and 48 control children, aged 5 to 16 years. Significantly more patients with epilepsy had psychiatric diagnoses compared with the control children. There were no statistically significant differences, however, in the number of patients with CPS and PGE with psychiatric diagnoses. Other than a schizophrenia-like psychosis found only in the patients with CPS, the two groups of patients had similar psychiatric diagnoses. The presence of psychopathology was related to significantly lower IQ scores and socioeconomic status, but not to seizure-related factors. These findings suggest that the psychopathology of children with CPS and PGE reflects different subtle neuropsychological deficits.     

Adjunctive therapy in epilepsy with new antiepileptic drugs: is it of any value?

A total of 97 patients were recruited into a prospective, follow-up study after they were prescribed an adjunctive antiepileptic drug. The patients were followed up over a 6-month period. The interview included questions on Quality of Life, side-effects, adverse events and seizure frequency and severity. We operationally defined patients 'satisfaction' as (i) still on new drug; (ii) experiencing no side-effects (iii) experiencing no adverse events and (iv) had a greater than 50% reduction in seizures. A total of 13 patients (17%) reported being 'satisfied' according to our operational definition.     

Frontal lobe epilepsy in infancy: is there a benign partial frontal lobe epilepsy?

INTRODUCTION: Only the organic and cryptogenic forms of frontal lobe epilepsy have been admitted by the ILAE, but according to several reports in the literature, it probably exists also an idiopathic form, at present not well recognized. OBJECTIVE: To study the differences between the organic and the cryptogenic forms of frontal epilepsy in our patients, that might indicate the presence of idiopathic cases within the presumed cryptogenic group. MATERIAL AND METHODS: All patients diagnosed of frontal lobe epilepsy, EEG registered, at the neuropediatric clinic of our hospital during 1993-1996, were selected: 30 patients under 14 years of age that were classified as organic (10 cases) or cryptogenic (20 cases) according to CT or MRI findings. The Mann-Whitney test and the Fisher exact test were performed for statistical analysis. Five patients with peculiar neurocognitive symptoms, epilepsy-related, are described in detail. RESULTS: Significative differences between the organic and cryptogenic forms of frontal lobe epilepsy were not found except for the tendency of cryptogenic EEG foci to spread beyond the frontal lobe, to generalize and to be associated with foci of other localizations. Epileptic status, either convulsive or not convulsive, were a frequent complication in both groups. CONCLUSIONS: The identification of an idiopathic form of frontal lobe epilepsy is difficult by its low prevalence as compared to the cryptogenic and organic forms, by the tendency of frontal seizures to become epileptic status, which predicts an intractable epilepsy, and by the clinical characteristics essential to frontal discharges: heterogeneity, frequent impairment of consciousness and specially the neurocognitive semiology, including dementia, that occurs as a critic or paracritic phenomenon, and that sometimes may develop or be accentuated by antiepileptic medication.     

Magnetoencephalography in partial epilepsy: clinical yield and localization accuracy

The goals of this study were to determine (1) the yield of magnetoencephalography (MEG) according to epilepsy type, (2) if MEG spike sources colocalize with focal epileptogenic pathology, and (3) if MEG can identify the epileptogenic zone when scalp ictal electroencephalogram (EEG) or magnetic resonance imaging (MRI) fail to localize it. Twenty-two patients with mesial temporal (10 patients), neocortical temporal (3 patients), and extratemporal lobe epilepsy (9 patients) were studied. A 37-channel biomagnetometer was used for simultaneously recording MEG with EEG. During the typical 2-3-hour MEG recording session, interictal epileptiform activity was observed in 16 of 22 patients. MEG localization yield was greater in patients with neocortical epilepsy (92%) than in those with mesial temporal lobe epilepsy (50%). In 5 of 6 patients with focal epileptogenic pathology, MEG spike sources were colocalized with the lesions. In 11 of 12 patients with nonlocalizing (ambiguous abnormalities or normal) MRI, MEG spike sources were localized in the region of the epileptogenic zone as ultimately defined by all clinical and EEG information (including intracranial EEG). In conclusion, MEG can reliably localize sources of spike discharges in patients with temporal and extratemporal lobe epilepsy. MEG sometimes provides noninvasive localization data that are not otherwise available with MRI or conventional scalp ictal EEG.     

Antiepileptic drugs and atypical evolution of idiopathic partial epilepsy

INTRODUCTION: Effectivity and application as well as possible complications and side effects of extracorporeal shock wave lithotripsy of plantar heel spurs should be evaluated. METHOD: We applied extracorporeal shock wave lithotripsy (ECSL) to treat plantar fasciitis in 54 patients (period from: 3/1/1993 to 3/1/1996). 20 persons were treated with Lithostar plus (group 1) and ultrasound focussing and 34 patients (group 2) were treated by a Lithostar and X-ray focussing. RESULTS: After 6 weeks 14 (70%) of group 1 and 27 (79.4%) of group 2 were free of pain. After 36.9 months 8 (40%) of group 1 and 23 (67.6%) of group 2 were still painfree. We could not recognize any severe complications after 36.9 months. CONCLUSION: ECSL is an effective and noninvasive method of treatment. It is not the method of choice for the first treatment of plantar fasciitis but is an alternative option for operation.     

Multiple sclerosis as a cause of partial complex epilepsy

INTRODUCTION: Although the epileptic seizures (ES) have been described on patients with multiple sclerosis (MS), the causal relationship is not clear. Seizure's prevalence in this illness is low and their apparition concerning the MS course is variable, but more common after MS diagnosis. The predominant crises are generalized or partial with secondary generalization; the partial complex seizures have rarely referred. CLINICAL CASES AND CONCLUSIONS: We presented two patients with ES in the MS course. In the first case is arrived to MS diagnosis upon appearing the crisis, having presented two previous cerebral lesions in another level. In both cases demyelinating lesion was located in the temporal lobe, agreeing with EEG anomaly and seizures type.     

MFT in complex partial epilepsy: spatio-temporal estimates of interictal activity

Following exposure of CHO-K1 cells to 137Cs irradiation at doses up to 20Gy, a delay in G2 was observed to occur in cells permitted to divide normally, while cells induced to become giants by means of cytochalasin B demonstrated a minimal delay in the transition 2C-8C suggesting that the inhibition of cytokinesis results in modification of one or more cell cycle checkpoints. We postulate that this may occur as a consequence of damage tolerance, or by a feedback loop resulting from the reorganisation of the cytoskeleton that precludes cytokinesis.