Clinical Neuroscience

[Surgical treatment of epilepsy]


JUNE 10, 2004

Clinical Neuroscience - 2004;57(05-06)

[In this article the possibilities, indications, methods and results of surgery in epilepsy are summarized in general with the Hungarian experience emphasized. Surgery may provide effective treatment in about 5-10% of the epileptic population. Surgical solution nowadays became an essential treatment in medial temporal epilepsy, if hippocampal sclerosis or other lesion is present, in therapy resistent lesional extratemporal epilepsies and in catastrophic childhood epilepsies if the epileptic disorder is restricted to one hemisphere (Rasmussen syndrome, hemimegalencephaly, Sturge-Weber disease and posttraumatic or postencephalitic hemispherial epilepsies). The algorhythms of the presurgical evaluation and the current methods for study the pacemaker area, forbidden zones, and hemispherial functions are treated. The currently used type and techniques of surgery, such as lesionectomy, temporal lobe resections, hemispherotomy, callosotomy, multiple subpial transsections and their indications are described. The newest surgical approaches, as deep brain stimulation, vagal nerve stimulation, and irradiation techniques are also briefly touched. Lastly, we deal with prognostical factors of the surgical outcome, reasons of surgical failures and complications. In a brief chapter the importance of postsurgical rehabilitation is emphasized.]



Further articles in this publication

Clinical Neuroscience

[Diagnosis of epilepsy]


[0.5-1% of the population suffers from epilepsy, while another 5% undergoes diagnostic evaluations due to the possibility of epilepsy. In the case of suspected epileptic seizures we face the following questions: Is it an epileptic seizure? The main and most frequent differential- diagnostic problems are the psychogenic non-epileptic seizures ("pseudo-seizures") and the convulsive syncope, which is often caused by heart disorders. Is it epilepsy? After an unprovoked seizure, the information on recurrence risk is an important question. The reoccurrence is more possible if a known etiological factor is present or the EEG shows epileptiform discharges. After an isolated epileptic seizure, the EEG is specific to epilepsy in 30-50% of cases. The EEG should take place within 24 hours postictally. If the EEG shows no epileptiform potentials, a sleep-EEG is required. What is the cause of seizures? Hippocampal sclerosis, benign tumors, and malformations of the cortical development are the most frequent causes of the focal epilepsy. Three potentially life-threatening conditions may cause chronic epilepsy: vascular malformations, tumors, and neuroinfections. The diagnosis in theses cases can usually be achieved by MRI, therefore, MRI is obligatory in all epilepsies starting in adulthood. The presence of epileptogenic lesion has a prognostic significance in treatment. If the MRI shows a circumscribed lesion then the pharmacological treatment will likely to be unsuccessful, while surgery may result in seizure freedom. The new and quantitative MRI techniques, such as volumetry, T2-relaxometry, MR-spectroscopy, and functional MRI play a growing role in the epilepsy diagnosis.]

Clinical Neuroscience

[Questions of epileptogenesis and prevention in symptomatic epilepsies]

NIKL János

[Symptomatic epilepsies usually report themselves after a longer period of time after brain injury, after the so-called latent period. During this period progressive functional and structural changes occur which finally cause an increased excitatory condition. The process of epileptogenesis may be examined in animal models, such as in the kindling, status epilepticus, hypoxicischaemic models. Data gained from such sources support the hypothesis that the first injury results in a lower seizure threshold, but genetical and enviromental factors also contribute to the development of epilepsy and most probably further insults may be needed. The development of epilepsy can be traced back to several reasons. In spite of this, the latent period provides opportunity for the prevention of epilepsy or for the influence of epileptogenesis in such a manner that later treatment can become more succesful. Prevention should be an aim in clinical practice, as well. Medication used presently are more like to have anticonvulsive properties and their antiepileptogenic effect is questionable. Due to this fact, development of new drugs is necessary with new theoretical background. The most important influence on the incidence of epilepsy in recent years has been provided by the improvement in neonatal care. This highlights the fact that such optimal medical care should be provided in the acute period of brain injury which can terminate or lessen the risk of epilepsy.]

Clinical Neuroscience

[Antiepileptic drug treatment]


[Antiepileptic drug treatment is essential and provides excellent therapeutic effects in more than the two-third of the epileptic patients. The antiepileptic drugs influence the chronic hyperexcitability of the brain developed during the epileptogenesis. As an effect, it decreases the excitability and/or increases the inhibition of the pathological cells, which prevents the precipitation of the epileptic seizure (anticonvulsive effect). The anticonvulsive effect comes into operation by the influence of the transport of one ore more ion-channels. The anticonvulsive effect is only symptomatic and it doesn’t cure the disorder. The drug selection is based on the knowledge of the therapeutic markers and the effectiveness of the drug to be used. This can occure on the basis of the action of the drug or in syndromespecific way. The pharmacokinetic properties of the drugs determine how they can be used in the practice. The drug interactions can take place in several levels. Among them, the change of the metabolism is the most important. Acute dosedependent side effects, organ-specific chronic interactions and idiosyncratic reactions must be taken into consideration during the use of antiepileptic drugs. The patient's individual aspects must be considerably taken into account during the treatment. There are other medical areas that can benefit from the antiepileptic drugs. Among them, the most important diseases are: restless legs syndrome, neuropathic pain, trigeminal neuralgia, essential tremor, bulimia and bipolar disorders. There are other pharmacological (adrenocorticotropic hormone, immunoglobulins, neurosteroids) and dietary methods, which may be effective at certain epileptic syndromes. The principles of the pharmacotherapy have been changing continuously during the past decades and since. New drugs have been introduced into the marketing and new expectations are coming into the limelight concerning the treatment. As a consequence this will bring on the modification of antiepileptic drug therapeutic habits.]

Clinical Neuroscience

[Hungarian Epilepsy League]

Clinical Neuroscience

[Genetic background of epilepsies]


[In this article we review epilepsies with monogenic inheritance. Most of these diseases are caused by abnormal function of ligand- and voltage gated ion channels caused by a genetic defect, therefore belonging to the channelopathies. From the inherited epilepsies the genetics of the autosomal dominant partial epilepsies is clarified the best. Mutations of the nicotinic acetylcholine receptor subunits are found in familial nocturnal frontal lobe epilepsy, while defects in the voltage gated potassium channels (KCNQ2 and KCNQ3) have been identified in benign familial neonatal convulsions. Familial temporolateral epilepsy was associated with mutations of a tumor suppressor gene. From the generalized epilepsies, the syndrome of generalized epilepsy with febrile seizures plus (GEFS+) can be caused by mutations of the sodium channel subunits and of the GABAA receptor subunits. These important results would probably lead to new findings in the genetics of the more common forms of idiopathic generalized epilepsies, which have presumed polygenic origin. Although without definite conclusions, sodium channel and GABA receptor dysfunction is presumed. The accumulated knowledge about channelopathies enables insight to the cellular mechanism of epileptogenesis as well.]

All articles in the issue

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Clinical Neuroscience

[10 years, 600 monitoring sessions - our experience with the video EEG monitoring of children]


[Introduction- The only Hungarian video EEG laboratorywhere children of ages 0-18 can be continuously monitoredfor several days was opened 1 June 2001 at Department ofNeurology of Bethesda Children’s Hospital.Objectives- Summarizing our 10 years of experience withthe video EEG monitoring (VEM) of children and defining theplace of VEM in the treatment of childhood epilepsy inHungary.Patients and methods- We have processed data from 597monitoring sessions on 541 patients between June 1, 2001and 31 May, 2011 based on our database and the detailedsummaries of the procedures. Results- 509 patients were under the age of 18. The average length of the sessions was 3.1 days. We haveobserved habitual episodes or episodes in question in 477(80%) sessions. 241 (40%) sessions were requested with anepilepsy surgery indication, and 74 patients had 84 opera-tions. 356 (60%) were requested with a differential diagnosisindication, and 191 (53%) cases of epilepsy werediagnosed. We most commonly diagnosed symptomaticgeneralized epilepsy (57 cases). In 165 sessions the episodein question was not diagnosed as epilepsy. Among theparoxysmal episodes we have identified events ofpsychogenic origin, movement disorders, sleep disordersand behavioral disorders. Only 3% of the differential diag-nosis procedures brought no additional clinical information.Discussion- The diagnostic efficiency in our VEM laborato-ry is in accordance with the data found in the literature.Besides epilepsy surgery VEM is recommended if suspectedepileptic episodes occur and interictal epileptiform signs arenot present or are not in accordance with the symptoms, ifthere is no explanation for therapy resistance and if paroxys-mal episodes of non-epileptic origin are suspected but theycannot be identified based on the anamnesis. VEM is also helpful in diagnosing subtle seizures. The procedure hasnumerous additional benefits in patient care and in trainingthe parents and hospital staff. ]

Clinical Neuroscience

[Neuropsychological outcome following bilateral pallidotomy in patients with Parkinson's disease]


[Introduction - Although significant improvement of motor function following bilateral pallidotomy for the treatment of Parkinsons's disease has been proved, the cognitive sequalae have not been clearly defined. There are recurrent loops interconnecting specific areas of the frontal cortex and the basal ganglia, suggesting the continuity or complementary functioning between these areas. Patients and methods - Pre- and postoperative cognitive function was evaluated in 19 Parkinsonian patients who underwent bilateral pallidotomy in order to clarify its effects on cognitive function. All patients were evaluated one day before the procedure and 12+ months after surgery using neuropsychological tests (Raven Progressive Matrices and Bergen Facial Recognition Test). Proper performance in these tests requires reasoning, abstraction and spatial memory, involving strongly the frontal functions. These functions could be described in terms of the ”working memory” concept. Hand Mental Rotation Test was used as comparing task not involving frontal functions. Scores were analyzed by Student’s t-test. Results - Modest improvement was observed in these cognitive functions as assessed by Raven Progressive Matrices (p<0.0688) and a significant change in the complex parts of Bergen Facial Recognition Test (p<0.0547; p<0.0468) was also noticed, but no change was registered in mental rotation tasks. Conclusion - Present data revealed that bilateral pallidotomy is associated with modest and long-lasting improvement in tasks involving the ”working memory”.]

Clinical Neuroscience

[The application of RBANS (Repeatable Battery for the Assessment of Neuropsychological Status) in neurocognitive testing of patients suffering from schizophrenia and dementia]

JUHÁSZ Levente Zsolt, KEMÉNY Katalin, LINKA Emese, SÁNTHA Judit, BARTKÓ György

[Introduction - The purpose of our study was to find out whether the Hungarian adaptation of the RBANS (Repeatable Battery for the Assessment of Neuropsychological Status), a brief neurocognitive screening test, is appropriate for the differentation of healthy and non-healthy subject groups, or for the detection of differences between the cognitive performance of patient groups. Patients and method - The test battery was administrated to 38 healthy subjects, 69 schizophrenic patients, and 18 patients suffering from dementia (10 probable Alzheimer-type and eight vascular dementia). Results - There was a significant decrease of performance in all patient groups compared to the healthy group. In the schizophrenic group, the test indicated a deterioration of functioning in all cognitive areas. The patient group with Alzheimer-type dementia performed only slightly better than the schizophrenic group, because the fall of performance was not significant only one of the cognitive areas (in the visuo-spatial tasks) when compared to the healthy group. There was no difference between the performance of patients with vascular dementia and that of healthy subjects in direct memory, verbal and visuo-spatial tasks. The test results indicated an even deterioration of cognitive areas in patients with Alzheimer-type dementia. As for the vascular dementia group, the most vulnerable area proved to be that of attention, while their verbal functions were relatively spared. The deterioration in other cognitive functions shown by schizophrenic subjects was more moderate, but still significant. A comparison of the RBANS scores of the schizophrenic patients in our study and the result of an American study was also carried out. The global indeces showed no difference; only the pattern of the sub-scales was a little different. Conclusion - The Hungarian version of the RBANS seems appropriate for the differentiation of healthy and deteriorated cognitive performance in a Hungarian patient population.]

Clinical Neuroscience

[Prolonged EEG-monitoring]


[Prolonged EEG monitoring and video-EEG monitoring are basic methods on the level of epilepsy centers. These methods are able to make differences between epilepsy and non epileptic paroxysmal manifestations like psychogenic non epileptic seizures, parasomniac phenomena, narcolepsy. The application of the method, at least the video-EEG variant, needs team work, high level organisation, highly educated staff and high tech electrographic devices. Running the method even with these requirements is beneficial from the cost-benefit aspect as well.]

Clinical Neuroscience

[Deep brain stimulation for treatment refractory obsessive-compulsive disorder - a case report]

CSIGÓ Katalin, DÖME László, HARSÁNYI András, DEMETER Gyula, RACSMÁNY Mihály

[In the last 30 years it has been a great development in the understanding and therapy of obsessive-compulsive disorder. Adequate pharmaco- and cognitive-behavior therapies reduce the symptoms in 40-60% of patients, so a remarkable portion of patients still remains refractory to conventional treatment. Neurosurgery - with it’s reversible and irreversible techniques - brought a breakthrough in the therapy of treatment refractory patients. In the present case, we represent a 3 months follow-up of an obsessive-compulsive patient treated by deep brain stimulation. In our case, the stimulation target was the anterior limb of internal capsule. The clinical symptoms were measured by Y-BOCS. In addition various neuropsychological tests were used to monitor patient’s executive functions before and 3 months after the deep brain stimulation. We found that obsessive-compulsive symptoms improved after three months of the stimulation. The neuropsychological tests showed improvement in some executive functions (e.g. fluency, set-shifting, decision making). On the other hand our results revealed severe neurocognitive - mainly attention skill - deficits in a treatment refractory obsessive-compulsive patient.]