Clinical Neuroscience

[New chapter in visual evoked potential studies - Clinical application of the multifocal vep method ]

JANÁKY Márta, PÁLFFY Andrea, BENEDEK Krisztina, BENEDEK György

DECEMBER 10, 2004

Clinical Neuroscience - 2004;57(11-12)

[The multifocal visual evoked potentials are the evoked responses over the visual cortex in response to the stimulation of circumscribed small areas in the central 30 degree region of the retina. The recording of multifocal visual evoked potentials was made possible by the computer algorhythm elaborated by Sutter in 1991. Multifocal electroretinograpy, developed upon the same theoretical principles, is already an routine clinical examination method for the topographic analysis of functional damages in the central part of the retina and for the differential diagnostics in neuro-ophthalmology. The multifocal visual evoked potential, however, has not been introduced into the clinical practice, although it displays the function of ganglion cells in a given region of the retina in a more detailed way than the sensitivity threshold in the perimetry. This examination makes the objective verification of defects possible in the visual pathway, too. In our department the recording of multifocal visual evoked potentials was started in 2002. In this paper we present the basics of this method and also deal with the problems concerning its application and its status in the history of visual evoked potentials.]

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[Dizziness - vertigo Warning symptoms in vertebrobasilar ischemia - Part I. ]

FAZEKAS András

[Dizziness and vertigo - like headache - are the most common complaints which leads 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.]

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[Immunomodulatory treatment in multiple sclerosis ]

CSÉPÁNY Tünde, BERECZKI Dániel

[During the past decade, several disease-modifying agents have been established and have become available for the treatment of multiple sclerosis. The disease-modifying agents could be grouped into immunomodulatory and immunosuppressive therapies altering the long-term course of multiple sclerosis. Therapy is now available for relapsing-remitting, secondary progressive and progressive-relapsing multiple sclerosis. Different disease-modifying agents became also available for the treatment of relapsing-remitting multiple sclerosis in Hungary which makes the therapeutic decision difficult. This overview might help to give an answer for different questions in the management of multiple sclerosis: Which agent to choose? When to initiate the therapy? Which dose to apply? Are the drugs safe? How long to treat the patients with immunomodulatory drugs? We give a review from the literature to assess the efficacy of disease-modifying therapies and to compare the data from phase three trials of interferon β1b, two preparations of interferon β1a or glatiramer acetate for the treatment of multiple sclerosis. We analyzed the efficacy and safety of these agents on physical, inflammatory and cognitive measures of disease activity. Comparison of study results indicated similar effects of immunomodulatory agents on relapse-related and inflammatory measures in relapsing multiple sclerosis. Interferon β1a slowed the progression of disability in relapsing multiple sclerosis. One interferon β1a preparation (intramuscularly injected) demonstrated efficacy in slowing progression of cognitive dysfunction. The interferons reduced relapses at early phase of secondary progressive multiple sclerosis, but their efficacy have not yet been proven in the later phase of secondary progressive multiple sclerosis without relapses. Mitoxantrone demonstrated efficacy in slowing the progression of disability in secondary progressive multiple sclerosis. All of the disease modifying agents are safe and tolerable, if the indication is correct and the patients are strictly controlled.]

Clinical Neuroscience

[The impact of neuroleptic medication on seizure threshold and duration in electroconvulsive therapy]

GAZDAG Gábor, BARNA István, IVÁNYI Zsolt, TOLNA Judit

[Introduction - In most patients diagnosed with psychotic depression or schizophrenia and treated with electroconvulsive therapy, parallelly administered antipsychotic medication cannot be stopped. Antipsychotic drugs can influence both seizure threshold and seizure activity in different ways. Patients and method - The present study processes the data of 77 patients treated parallelly with electroconvulsive therapy and antipsychotic drugs. Oral doses of the antipsychotic medication administered the day before the electroconvulsive therapy, stimulus intensity, seizure durations, and impedance were analysed from session to session. Results - One group of antipsychotics (haloperidol, fluphenazine, risperidone, sulpirid) was not found to influence seizure activity: there was no significant difference in EEG and EMG registered seizure duration or in stimulus intensity between the treated and non-treated group. However, significant difference was found between the next treated and non-treated groups in 40% of the sessions in case of olanzapine, in 50% of the sessions in case of clozapine and in 57% of the sessions in case of zuclopenthixol in EEG or EMG registered seizure duration as well as in stimulus intensity. In the third group (quetiapine) there was a significant difference in each session (2nd session: EMG, p=0.02; 5th session: EEG, p=0.05, EMG, p=0.04). Most of the antipsychotics (olanzapine, clozapine, zuclopenthixol) have been shown to possess epileptogenic properties; only quetiapine reduces seizure activity. Conclusion - In the clinical use of olanzapine, clozapine and zuclopenthixol seems epileptogenic, whereas in the case of quetiapine seizure reducing properties must be taken into account. Together with the consideration of the accompanying somatic and neurologic disturbances and with the concomitant medications this can influence the treatment of choice.]

Clinical Neuroscience

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[Introduction - Dementia is a decline of intellectual abilities. The etiology of dementia syndrome is diverse. The authors describe three patients with early-onset dementia. Case reports - The first patient was a 44 years old male with mild gait, body ataxia, memory loss, slowness and apathy. Investigations proved AIDS dementia syndrome. In the second case of a 37 years old female patient, herpes simplex encephalitis was suspected due to sudden onset of speech arrest and to brain MRI and CSF findings. Her symptoms improved during antiviral treatment but later progressive dementia developed. CSF serological tests proved the presence of neurolues-dementia paralytica. The third patient was a 38-years-old female. Neurological examination was performed because of progressive memory loss, changed behaviour and impaired attention. Neuropsychological test showed severe dementia. Metachromatic leukodystrophy was proven by decreased arylsulfatase activity. Conclusions - It is not easy to recognize the early symptoms of dementia. In these cases, besides detailed history, neurological examination and neuropsychological tests, brain MRI and cerebral spinal fluid serological tests were indispensable for a correct diagnosis, especially in the young patients.]

Clinical Neuroscience

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[Introduction - Anaplastic astrocytomas and glioblastomas are the most frequent and most malignant hemispherial tumours. Unfortunately, astrocytic tumours are of infiltrative character and radical removal is not possible. Recurrent malignant gliomas are rarely suitable for reoperation. In most of the cases of recurrent gliomas chemotherapy is the last choice. Patients and method - Seventy-five consecutive patients with recurrent malignant astrocytomas and glioblastomas had been treated at our institute with per os temozolomide for five days every month. The patients received two to 16 courses of chemotherapy. The toxicity, quality of life, response to chemotherapy and survival data were analysed. Results - Out of 75 patients four were excluded following the first treatment due to myelotoxicity, and allergic reactions. Among the patients treated with temozolomide in seven cases complete response, 17 partial response, 14 progressive disease were observed. In 33 cases the disease stabilized and out of them in 27% a significant neurological improvement was detected. The time to progression was 6.8 months and the median survival time 8.75 months for patients with glioblastoma and with malignant astrocytoma or malignant mixed oligoastrocytoma 9.45 and 11.15 months, respectively. The overall survival for patients with originally lower grade glioma was 70.32 and for patients with glioblastoma multiforme 17.43 months. Conclusions - Temozolomide chemotherapy in patients with recurrent malignant astrocytoma and glioblastoma proved to be efficacious and similar good results were achieved as with a nitrosourea based combined chemotherapy. Even in those patients who received previous chemotherapy temozolomide is well tolerated and a relatively long time to progression was achieved in cases of recurrent malignant gliomas. In a few number of patients where BCNU had been previously failed with temozolomide stable disease was achieved. Temozolomide seems to be a promising drug in the chemotherapy of malignant gliomas and can be applied as a second line chemotherapy, as well.]

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Clinical Neuroscience

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Clinical Neuroscience

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Clinical Neuroscience

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