Clinical Neuroscience

[THE PERISYLVIAN EPILEPTIC NETWORK A unifying concept]

HALÁSZ Péter, KELEMEN Anna, CLEMENS Béla, SARACZ Judit, ROSDY Beáta, RÁSONYI György, SZŰCS Anna

JANUARY 20, 2005

Clinical Neuroscience - 2005;58(01-02)

[In this work the authors provide evidences for a unifying concept of the syndromes of benign focal childhood epilepsies, Landau-Kleffner syndrome, and electrical status epilepticus in sleep treating them as a spectrum of disorders with a common transient, age dependent, non lesional, genetically based epileptogenic abnormality, the nature of which is still not known. The electro-clinical features of these syndromes are congruent with the different degree involvement of the perisylvian cognitive network and with the involvement of the thalamo-cortical associative system of variable degree. These epilepsies are characterized by the abundance of regional epileptiform discharges in sharp contrast with the rare and in several cases lacking seizures. The nature and severity of interictal cognitive symptoms are closely related to localization within the network and amount of epileptic interictal discharges. Spike-wave discharges are attributed to an alternation of overexcitation (spikes) and overinhibition (waves). The recurrent overinhibition represented by the wave of the discharges may interfere with the continuous depolarization of the cells of a large population of neurons, which is a requirement of the overt seizures. The overinhibition also interfere with cognitive processes which are correlated with the continuous presence of the fast (gamma) activity, binding the required cortical areas. Hence the recurrent inhibition works against the existence of the binding fast frequency activity. This is the assumed reason for the co-existence of the relative lack of overt seizures and in the same time for the frequently observed epileptogenic cognitive deficit symptoms ("cognitive epilepsies"). The time course of these syndromes overlaps with important developmental milestones. The frequent epileptic discharges alters the evolution of the perisylvian network developing late after early childhood and is very vulnerable for any interference in this imprinting time for speech and other cognitive functions. This spectrum of disorders represents a type of age linked, mild to severe ‘epileptic encephalopathy’ limited to the perisylvian network, where the cognitive impairment is underlied by epileptic discharges interfering with cognitive development.]

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Clinical Neuroscience

[DIZZINESS - VERTIGO WARNING SYMPTOMS IN VERTEBROBASILAR ISCHEMIA PART II.]

FAZEKAS András

[Dizziness and vertigo - like headache - are the most common complaints which lead patients to visit the doctor. In spite of the headache - which may be primary (e.g. migraine) or symptomatic - dizziness and vertigo do not appear to be a separate nosologic entity but rather the symptoms of several neurological disorders. For differential diagnosis, interdisciplinary thinking and activity is needed because the vestibular, neurological and psychiatric disorders might have a common role in the development of symptoms and further overlapping can also occur. The vascular disorders of the vertebrobasilar system are discussed in detail in this review. The importance, occurrence and causes of vertigo as a warning symptom is in the focus. The author draws attention to life-threatening conditions with acute onset in cases of the posterior scale ischemia and emphasizes the importance of the correct and early diagnosis. The author tries to clear up the nihilistic aspect in treating of stroke and stresses the necessity of thrombolysis and interventional radiological procedures which may be the only chance for the recovery of the patients. The pharmacological prevention of recurrent vascular events is also important and obligatory for the clinicians.]

Clinical Neuroscience

[CHRONIC INFLAMMATORY POLYNEUROPATHIES]

BENICZKY Sándor, VÉCSEI László

[There is an increasing number of peripheral nerve disorders with inflammatory and immune mechanisms involved. The precise diagnosis is of utmost importance, since these patients can be successfully treated. Unfortunately, there is no specific marker for any disease of this group. The diagnosis therefore relies on the appropriate consideration of the clinical, neurophysiological and laboratory data, which requires in-depth knowledge of these diseases. In this paper we review the diagnostic criteria and treatment strategies for the major types of chronic inflammatory polyneuropathies.]

Clinical Neuroscience

[EXAMINATION OF NATURAL COAGULATION INHIBITOR PROTEINS IN THE ACUTE PHASE OF ISCHAEMIC ST]

OLÁH László, CSÉPÁNY Tünde, BERECZKY Zsuzsanna, KERÉNYI Adrienne, MISZ Mária, KAPPELMAYER János, CSIBA László

[Introduction - Decreased activity of natural anticoagulants (antithrombin-III, protein C, protein S) rarely causes cerebral ischaemia, however it can be found frequently in acute phase of ischaemic stroke. The authors’ aim was to investigate whether the decreased activity of natural anticoagulants is accompanied by worsening of symptoms in ischaemic stroke. Patients and method - Sixty-eight acute ischaemic stroke patients were investigated. Severity of symptoms were assessed and followed by the NIH Stroke Scale. Antithrombin- III, protein C, protein S activities, and concentration of C-reactive protein (CRP) were measured within 48 hours after onset of ischaemic stroke. Results - Progressing stroke was found in 29% of patients. Decreased activity of at least one natural anticoagulant proteins was present in 31% of patients. Progression of stroke symptoms occured in 76% of patients with decreased natural anticoagulant activity, while this proportion was only 9% in those with normal natural coagulation inhibitor protein activity (p<0.01). Progressing stroke was also more frequent in patients with elevated CRP value (60%) than in those with normal CRP level (11%; p<0.05). Decreased activity of natural anticoagulants was more frequent in patients with elevated CRP concentration compared with patients with normal CRP. Conclusion - The results demonstrate the importance of decreased activity of natural anticoagulants in acute phase of ischaemic stroke. This abnormality was present in about 1/3 of stroke patients. The decreased activity of natural coagulant inhibitor proteins may play an important role in development of progressing stroke thus indicating unfavourable outcome.]

Clinical Neuroscience

[EXPERIMENTAL DEMYELINATION CAUSED BY PRIMARY OLIGODENDROCYTE DYSTROPHY Regional distribution of the lesions in the nervous system of mice brain]

KOMOLY Sámuel

[Background and purpose - Heterogeneity of multiple sclerosis lesions has been recently indicated: In addition to T-cell-mediated or T-cell plus antibody-mediated autoimmune mechanisms (patterns I-II) two other patterns (III-IV) were described. Patterns III-IV are characterized by primary oligodendrocyte dystrophy, reminiscent of virus- or toxin-induced demyelination rather than autoimmunity. It was described more than 30 years ago that dietary application of a copper-chelating agent called cuprizone results in primary oligodendrocyte degeneration which is followed by demyelination. The aim of the present study was to examine the regional distribution of cuprizone induced oligodendrocyte dystrophy and demyelination in the nervous system of mice. Material a methods - Demyelination was induced in male weanling Swis-Webster mice by feeding them on a diet containing 0.6% (W/W) cuprizone bis(cyclohexanone)-oxalyldihydrazone (G. F. Smith Chemical, Columbus OH) for 8 weeks. Animals were sacrificed after 3, 7, 14, 27, 35, 56 days of cuprizone administration. Samples were taken from corpus callosum, anterior commissure, optic nerve, cervical spinal cord and sciatic nerve. Samples were examined by immunohistochemistry, in situ hybridization for myelin proteins and myelin protein mRNA-s, respectively. Conventional neuropathological stainings and electron microscopy was also performed. Results - Oligodendrocyte degeneration and demyelination followed a particular standard pattern in the central nervous system. Profound myelin loss developed in the superior cerebellar peduncle, anterior comissure and corpus callosum, whereas the optic nerves, velum medullare anterior and spinal cord showed little or no demyelination. Sciatic nerves were unaffected. No infiltration by lymphocytes or blood-brain barrier damage was observed during cuprizone treatment. Conclusion - Cuprizone induced oligodendrocyte damage and demyelination follows a particular standard pattern in the central nervous system of mice. Cuprizone induced demyelination might be considered as a model for human demyelinating disorders with primary oligodendrocyte dystrophy and apoptosis.]

Clinical Neuroscience

[CLINICAL FEATURES OF CORTICOBASAL DEGENERATION]

FARSANG Marianna, TAKÁTS Annamária, SZIRMAI Imre, KOVÁCS Tibor

[Corticobasal degeneration was described in 1968 by Rebeiz, Kolodny and Richardson, who characterized the disease as a syndrome of asymmetric akinesis and rigidity, dystonia of the upper limb, apraxia, myoclonus and dementia. Atrophy of the frontal and parietal lobe, neuronal loss, gliosis and achromatic neurones (and nowadays astrocytic plaques) are the characteristic pathological features of the disease. Corticobasal degeneration is a rare or a rarely recognized disease and it is frequently misdiagnosed as Parkinson’s disease. According to the Lang’s criteria, corticobasal degeneration can be diagnosed in the presence of rigidity and one cortical symptom (apraxia, cortical sensory loss, alien hand) or in a patient with rigidity, dystonia and focal reflex myoclonus. Exclusion criteria are early dementia (as in primary degenerative dementias), early vertical gaze problems (as in progressive supranuclear palsy), resting tremor and good, sustained therapeutic response to levodopa (as in Parkinson’s disease), severe autonomic problems (as in multiple system atrophy) and any pathology on imaging studies which might explain the clinical symptoms. It should be mentioned, that recently early dementia is recognized as an initial symptom of corticobasal degeneration. The authors present a case and review the literature to call attention to this disorder.]

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Simultaneous subdural, subarachnoideal and intracerebral haemorrhage after rupture of a peripheral middle cerebral artery aneurysm

BÉRES-MOLNÁR Anna Katalin, FOLYOVICH András, SZLOBODA Péter, SZENDREY-KISS Zsolt, BERECZKI Dániel, BAKOS Mária, VÁRALLYAY György, SZABÓ Huba, NYÁRI István

The cause of intracerebral, subarachnoid and subdural haemorrhage is different, and the simultaneous appearance in the same case is extremely rare. We describe the case of a patient with a ruptured aneurysm on the distal segment of the middle cerebral artery, with a concomitant subdural and intracerebral haemorrhage, and a subsequent secondary brainstem (Duret) haemorrhage. The 59-year-old woman had hypertension and diabetes in her medical history. She experienced anomic aphasia and left-sided headache starting one day before admission. She had no trauma. A few minutes after admission she suddenly became comatose, her breathing became superficial. Non-contrast CT revealed left sided fronto-parietal subdural and subarachnoid and intracerebral haemorrhage, and bleeding was also observed in the right pontine region. The patient had leucocytosis and hyperglycemia but normal hemostasis. After the subdural haemorrhage had been evacuated, the patient was transferred to intensive care unit. Sepsis developed. Echocardiography did not detect endocarditis. Neurological status, vigilance gradually improved. The rehabilitation process was interrupted by epileptic status. Control CT and CT angiography proved an aneurysm in the peripheral part of the left middle cerebral artery, which was later clipped. Histolo­gical examination excluded mycotic etiology of the aneu­rysm and “normal aneurysm wall” was described. The brain stem haemorrhage – Duret bleeding – was presumably caused by a sudden increase in intracranial pressure due to the supratentorial space occupying process and consequential trans-tentorial herniation. This case is a rarity, as the patient not only survived, but lives an active life with some residual symptoms.

Clinical Neuroscience

Valproic acid associated pleuropericardial effusion: case report

DEMIR Figen Ulku

Introduction - Valproic acid is an effective antiepileptic and mood stabilizer used in the treatment of many neurological and psychiatric disorders. Although there are frequently seen side effects, effusions between layers of pleural and pericardial membranes are rare to be seen. Case - Pleuropericardial effusion was detected in a 23 years old woman who was under valproic acid treatment because of epileptic seizure. After 1 year of valproic acid treatment, patient complained of dyspnea. As all the researches intended on etiology were usual, valproic acid has been thought to be responsible for the matter. Control examination after 1.5 months regarding the end of treatment revealed complete recovery of pleuropericardial effusion. Discussion - Pleural and pericardial effusions are rarely seen complications related to the use of valproic acid. It must also be kept in mind that valproic acid causes a potential for such side effects which can be blamed etiologically when the other possibilities for patients are excluded.

Clinical Neuroscience

Effects of valproate, carbamazepine and levetiracetam on Tp-e interval, Tp-e/QT and Tp-e/QTc ratio

YASAR Altun, ERDOGAN Yasar

Aim - To evaluate P-wave dispersion before and after antiepileptic drug (AED) treatment as well as to investigate the risk of ventricular repolarization using the Tpeak-Tend (Tp-e) interval and Tp-e/QT ratio in patients with epileptic disorder. Methods - A total of 63 patients receiving AED therapy and 35 healthy adults were included. ECG recordings were obtained before and 3 months after anti-epileptic treatment among patients with epilepsy. For both groups, Tp-e and Tp-e/QT ratio were measured using a 12-lead ECG device. Results - Tp-e interval, Tpe/QT and Tp-e/QTc ratios were found to be higher in the patient group than in the control group (p<0.05, for all), while QTmax ratio was significantly lower in the patient group. After 3 months of AED therapy, significant increases in QT max, QTc max, QTcd, Tp-e, Tp-e/QT, and Tp-e/QTc were found among the patients (p<0.05). When the arrhythmic effects of the drugs before and after treatment were compared, especially in the valproic acid group, there were significant increases in Tp-e interval, Tp-e/QT and Tp-e/QTc values after three months of treatment (p<0.05). Carbamazepine and levetiracetam groups were not statistically significant in terms of pre- and post-treatment values. Conclusions - It was concluded that an arrhythmogenic environment may be associated with the disease, and patients who received AED monotherapy may need to be followed up more closely for arrhythmia.

Clinical Neuroscience

[Zonisamide: one of the first-line antiepileptic drugs in focal epilepsy ]

JANSZKY József, HORVÁTH Réka, KOMOLY Sámuel

[Chronic administration of antiepileptic drugs without history of unprovoked epileptic seizures are not recommended for epilepsy prophylaxis. Conversely, if the patient suffered the first unprovoked seizure, then the presence of epileptiform discharges on the EEG, focal neurological signs, and the presence of epileptogenic lesion on the MRI are risk factors for a second seizure (such as for the development of epilepsy). Without these risk factors, the chance of a second seizure is about 25-30%, while the presence of these risk factors (for example signs of previous stroke, neurotrauma, or encephalitis on the MRI) can predict >70% seizure recurrence. Thus the International League Against Epilepsy (ILAE) re-defined the term ’epilepsy’ which can be diagnosed even after the first seizure, if the risk of seizure recurrence is high. According to this definition, we can start antiepileptic drug therapy after a single unprovoked seizure. There are four antiepileptic drugs which has the highest evidence (level „A”) as first-line initial monotherapy for treating newly diagnosed epilepsy. These are: carbamazepine, phenytoin, levetiracetam, and zonisamide (ZNS). The present review focuses on the ZNS. Beacuse ZNS can be administrated once a day, it is an optimal drug for maintaining patient’s compliance and for those patients who have a high risk for developing a non-compliance (for example teenagers and young adults). Due to the low interaction potential, ZNS treatment is safe and effective in treating epilepsy of elderly people. ZNS is an ideal drug in epilepsy accompanied by obesity, because ZNS has a weight loss effect, especially in obese patients.]

Clinical Neuroscience

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