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S Kochen

Publications and source records attributed to S Kochen.

15 recordsLinked to original sources

Spike-and-wave complexes and seizure exacerbation caused by carbamazepine.

The purpose of this research is to analyse patients in whom carbamazepine (CBZ) therapy adversely affected electroencephalogram (EEG) recordings leading to seizure exacerbation and to identify risk factors for these events. From a total number of 2191 patients (p.) included in the Municipal Epilepsy Center (MEC) database, 77 patients with spike-and-wave (SW) discharges while on CBZ treatment have been selected. Patient population was divided in two groups: (i) patients who were already receiving CBZ at the time of their first visit to the MEC; and (ii) patients to whom CBZ was prescribed during follow-up at the MEC. CBZ was discontinued in all patients with confirmed evidence of an increase in seizure frequency, or with no improvement of epilepsy. During follow-up, EEG findings as well as all clinical changes were duly recorded. Group 1: Carbamazepine was discontinued in 17 patients (p.) as a result of paradoxical reactions. This condition occurs when an antiepileptic drug (AED) appears to exacerbate a type of seizure against which it is usually effective, or when it leads to the onset of new types of seizures. Three p. were withdrawn because of inappropriate drug selection. Group 2: CBZ was discontinued in six patients (p.) as a result of paradoxical reactions. The paradoxical reaction was more frequent in patients with frontal epilepsy and generalized SW discharges on the EEG (P=0.09) and patients with benign rolandic epilepsy (BRE) with diffuse interictal sharp and slow-wave discharges. In both groups, clinical and electrical changes returned to their initial status upon CBZ withdrawal. On the basis of this study, it may be concluded that EEGs might eventually help to screen high-risk patients. If EEG recordings become substantially worse, with more frequent and longer generalized SW bursts after initiation of CBZ therapy, patients should be carefully monitored in order to detect any sign of clinical impairment.

Adolescent↗

Clinical features and prognosis of nonepileptic seizures in a developing country.

PURPOSE: To determine the predictive value of clinical features and medical history in patients with nonepileptic seizures (NESs). METHODS: One hundred sixty-one consecutive ictal video-EEGs were reviewed, and 17 patients with 41 NESs identified. NES diagnosis was defined as paroxysmal behavioral changes suggestive of epileptic seizures recorded during video-EEC without any electrographic ictal activity. Clinical features, age, sex, coexisting epilepsy, associated psychiatric disorder, social and economic factors, delay in reaching the diagnosis of NES, previous treatment, and correlation with outcome on follow-up were examined. RESULTS: The study population included 70% female patients with a mean age of 33 years. Mean duration of NESs before diagnosis was 9 years. Forty-one percent had coexisting epilepsy. The most frequent NES clinical features were tonic-clonic mimicking movements and fear/anxiety/hyperventilation. The most common psychiatric diagnosis was conversion disorder and dependent and borderline personality disorder. Seventy-three percent of patients with pure NESs received antiepileptic drugs (AEDs), and 63.5% of this group received new AEDs. Fifty-nine percent of the patients received psychological/psychiatric therapy. At follow-up, 23.5% were free of NESs. CONCLUSIONS: All seizure-free patients had two good prognostic factors: having an independent lifestyle and the acceptance of the nonepileptic nature of the episodes. Video-EEG monitoring continues to be the diagnostic method to ensure accurate seizure classification. Establishing adequate health care programs to facilitate access to new technology in public hospitals as well as the implementation of continuous education programs for general practitioners and neurologists could eventually improve the diagnosis and treatment of patients with NESs.

Adolescent↗

[Mesial temporal sclerosis syndrome in adult patients].

Magnetic resonance imaging (MRI) has become an essential tool in the work-up of epilepsy. Since its appearance it has been possible to identify pathologies, such as hippocampal sclerosis (HS), that had previously only been detected by histopathological assays. The aim of this study was to analyze the clinical manifestations, EEG and the outcome of patients with HS as shown by MRI. We revised the clinical histories of 384 outpatients from the Epilepsy Center, Ramos Mejía Hospital, who had been studied by MRI. Thirty five of them (15.5%) had a diagnosis of HS, based on the structural changes observed on the images. Six patients were excluded because of incomplete clinical data. Therefore, we studied 29 patients including 15 men. The mean age was 32.7 +/- 10.2 years (range: 19-58). All of them had partial seizures. Ten subjects had had febrile convulsions (34.5%) in childhood. Neurological examination was normal in all subjects. Interictal EEG showed focal abnormalities that were coincident in their location with the MRI abnormalities in 16 patients (55.1%). Fourteen patients (48.3%) showed right side hippocampal lesions on MRI, thirteen on the left side (44.9%) and 2 bilateral HS (6.8%). Twenty-seven patients (93.1%) had intractable epilepsy. Anterior temporal lobectomy was performed in 3 subjects with good outcome. The identification of these patients who present certain clinical and MRI characteristics, provides an opportunity to define the mesial temporal sclerosis syndrome. This could benefit patients in their prognosis and for specific treatments.

Adult↗

Seizures of temporal lobe epilepsy: identification of subtypes by coherence analysis using stereo-electro-encephalography.

OBJECTIVES: Two subtypes of temporal lobe epilepsy (TLE) according to the structures initially involved during seizures are currently recognized: medial TLE (MTLE) and lateral (or neocortical) TLE (LTLE). A few reports have suggested that the classification of TLE subtypes might be larger according to variations in the interactions between medial structures and the neocortex. In this study, we analyzed these interactions using coherence analysis of stereo-encephalographic (SEEG) signals during spontaneous seizures. METHODS: Twenty-seven patients with drug-resistant TLE, diagnosed from ictal SEEG recordings obtained during pre-surgical evaluation, were studied. Orthogonally implanted depth electrodes with multiple leads according to Talairach's method were used to sample medial and neocortical structures. Coherence analysis of ictal discharges was performed between two SEEG bipolar signals from adjacent leads located either in medial structures (amygdala and hippocampus) or in neocortical regions of the temporal lobe. A new algorithm, which was designed to reduce the bias inherent in coherence estimation, was used to compute the coherence. RESULTS: We were able to classify TLE seizures (TLES) into 4 distinct categories: (1) 'medial' TLES, characterized by medial onset with later involvement of the neocortex in the form of a 'phasic' discharge. High ictal coherence values were observed between medial structures; (2) 'medial-lateral' TLES which started in medial structures with a fast low-voltage discharge (FLVD) which rapidly affects the neocortex (< or = 3 s). High coherence values were observed between medial and lateral structures; (3) 'lateral-medial' TLES, which are different from medial-lateral TLES in that the FLVD starts in the lateral neocortex and involves the amygdala and/or hippocampus almost immediately after; (4) 'lateral' TLES: characterized by a neocortical onset, a delayed involvement of medial structures (when present), and high coherence values between neocortical structures. CONCLUSIONS: These results demonstrate the existence of numerous interactions between medial limbic structures and the neocortex during TLE seizures. Such findings could have implications for surgical strategies and the prognosis of epilepsy surgery, particularly when limited resection is indicated.

Adolescent↗

A double-blind controlled clinical trial of oxcarbazepine versus phenytoin in adults with previously untreated epilepsy.

In the last 5 years oxcarbazepine (OXC) has been registered in many countries for use as first-line and add-on treatment for partial seizures with or without secondarily generalized seizures (PS) and generalized tonic-clonic seizures without partial onset (GTCS). Its use as monotherapy in adults with newly diagnosed epilepsy was investigated in this double-blind, randomized, parallel-group comparison with phenytoin (PHT). A total of 287 adult patients, with either PS or GTCS, were randomized. After retrospective baseline assessment, patients were randomized to OXC or PHT in a 1:1 ratio. The double-blind treatment phase was divided into two periods: a flexible titration period of 8 weeks, followed by 48 weeks of maintenance treatment. In the efficacy analyses, no statistically significant differences were found between the treatment groups. Seventy patients (59.3%) in the OXC group and 69 (58.0%) in the PHT group were seizure-free during the maintenance period. A total of 56 of the patients in the OXC group discontinued treatment prematurely (five because of tolerability reasons) compared to 61 in the PHT group (16 for tolerability reasons). The number of premature discontinuations due to adverse experiences showed a statistically significant difference in favour of OXC. There was no statistically significant difference between the groups with respect to the total number of premature discontinuations. This trial provides further support for the efficacy and safety of OXC as first-line treatment in adults with PS and GTCS. In addition, the results show that OXC has significant advantages over PHT in terms of tolerability.

Adolescent↗

[Status of cerebral cortical excitability in juvenile myoclonus epilepsy].

The myoclonic epilepsies constitute an heterogeneous group of entities characterized by primary generalized seizures, whose common critical manifestation is myoclonus. Within this group there is a subset of patients, identified by Janz in 1955 as "Impulsive petit mal" and later named "Janz juvenile myoclonic epilepsy" (JJME) by Delgado-Escueta. Its most important clinical features are myoclonus, expressed as mild to moderate jerks of neck, shoulders and arms. These jerks are more frequent when awakening; they can be caused by sleep deprivation and emotional stress, without consciousness impairment. Usually neurologic examinations and mental status are normal. Response to specific treatment is good, with disappearance of seizures in most patients. We attempted to assess the pathophysiologic mechanisms involved in this kind of epilepsy. The existence of differences or similarities with the findings described in the other forms of myoclonic epilepsy was specially considered. In 14 patients with JJME, we performed C reflex studies with negative results. The mean amplitude of somato sensitive evoked potential (SSEP) was around 5 microV (normal values: 2.5 microV) in its different components. Shibasaki et al. suggested that the amplitude increase could be related to a cortical excitability increase at the somatosensory and motor level, which is the probable site of the epileptogenic area. Within the patient group with myoclonic progressive epilepsy (EMP) and continuous partial epilepsy (CPE), SSPEs amplitude ranged from 8 microV to 40 microV. In our patient group, the increase in SSPEs amplitude was smaller than the one observed in the other two entities. However, it was significantly higher than the mean value for the normal population.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[The role of the temporal cortex in long-latency auditory evoked potentials].

There is no definite agreement on the localization of the PEAL generators. However, some authors have claimed that the temporal auditive cortex plays a role. Based on these assumptions we searched for the eventual changes developing in PEALs in patients who applied for temporal epilepsy, where the temporal cortex activity is somehow impaired. Altogether 19 patients were explored. The results were compared with 17 matched healthy controls and 4 patients with focal epilepsy who, at the time of the study, received the same treatment as the temporal epileptic subjects. In every case PEATs and PEALs were studied. One thousand Hz less than time monoaural stimulation, 50 db and 50 ms duration was employed for evoking PEALs. Recording was done with surface electrodes located at Cz, F3 and F4 coupled with an electrode placed at the contralateral mastoid; 500 ms sweep were averaged. Band-pass was set up between 1 and 125 Hz and latencies and amplitudes were studied for both types of evoked responses, PEATs and PEALs. No statistical difference was found between patients and both control groups when PEATs mean parameters were analyzed. For further PEALs results, patients were divided into 3 groups; a) Those with right temporal epilepsy (n = 6) (R); b) Those with left temporal epilepsy (n = 7) (L); c) Those in whom the affected side could not be determined (n = 7) (N). In R it was observed, when stimulating the left ear, a delay in the arrival of P1 (F4 mea 87 +/- 10.4 ms) and N1 (F4 mean 122.33 +/- 6.1 ms; Cz mean 170.75 +/- 18.8 ms) waves.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Self-help epilepsy groups: an evaluation of effect on depression and schizophrenia.

The general prevalence of depression and schizophrenia was determined in a random outpatient population (n = 67) of refractory epileptic patients by Minnesota Multiphasic Personality inventory (MMPI) and Beck Depression Inventory (BDI). Of those patients 25% showed scores of moderate or severe depression. Self-help group intervention modifies significantly (p < 0.001) general mean depression rates, especially dystimia. Male and female differences emerged in our study for previous prevalence and pattern of recovery.

Adult↗

[Partial non convulsive epileptic status as initial presentation of limbic encephalitis].

INTRODUCTION: Limbic encephalitis is an unusual presentation of paraneoplastic syndrome, which includes among its symptoms seizures. CLINICAL CASE: We report a case with a rare presentation of limbic encephalitis as initial symptom of small cell lung carcinoma. A 69 year-old woman presented with partial non convulsive status epilepticus and neuropsychiatric disturbances. Chest radiography and computed tomography showed mediastinal lymphadenopathy and lung nodules. Subsequently, small cell lung carcinoma was diagnosed by lymph node biopsy. The cerebrospinal fluid study was normal. The electroencephalography and magnetic resonance imaging (MRI) findings had distinctive features compatible with temporo-limbic dysfunction. The anti-Hu antibodies were negative. The neuropsychiatric symptoms improved significantly after systemic chemotherapy and adjuvant radiotherapy. A serial follow-up MRI of the head showed no evidence of intracranial metastasis three months after the diagnosis of cancer. Limbic encephalitis may be an initial manifestation of lung cancer. Paraneoplastic limbic encephalitis is considered a remote effect of cancer commonly associated with anti-neuronal antibodies (anti-Hu) and small cell lung carcinoma. CONCLUSIONS: Status epilepticus could be an early sign of limbic encephalitis. The absence of anti-Hu antibodies does not rule out the presence of an underlying small cell lung carcinoma in patients with a clinical diagnosis of limbic encephalitis. Greater awareness for diagnosis and early treatment of the primary tumor offers the best chance for improvement in patients with lung cancer presenting with limbic encephalitis.

Aged↗

[Esquizofreniform psychosis after epilepsy surgery. A case of forced normalization fenomena].

The present case report is about the development of a eschizophreniform psychosis after epilepsy surgery (anterior temporal lobectomy). This adverse event was the novo, in a patient without a history of previous psychosis. This case have been studied pre and post-surgery, and have been used the DSM IV diagnosis criteria. The patient developed a subacute alucinatory-delusion syndrome, while seizures disappeared. This inverse relationship is an example of alternative psychosis or forced normalization after surgery treatment. This clinic example may us think about the controversial relationship between temporal epilepsy and psychosis.

Adult↗