Clinical Neuroscience

[Neurosurgical ways…]

CSÓKAY András

JANUARY 30, 2006

Clinical Neuroscience - 2006;59(01-02)

COMMENTS

0 comments

Further articles in this publication

Clinical Neuroscience

[COMPLEX TREMOR ANALYSIS FOR THE DIFFERENTIAL DIAGNOSIS OF ESSENTIAL TREMOR AND PARKINSON’S DISEASE]

FARKAS Zsuzsanna, CSILLIK Anita, PÁLVÖLGYI László, TAKÁCS Annamária, SZIRMAI Imre, KAMONDI Anita

[Objective - Tremor is the most common movement disorder which is most often either essential or caused by Parkinson’s disease. The differentiation of these disorders at the initial stage may be difficult. Objective assessment of the efficacy of tremor medications is only possible by instrumental measurements. The aim of this study was to determine whether the computer assisted tremor analysis system CATSYS 2000 can help in the differentiation of parkinsonian from essential tremor. Methods - The rhythmicity and maximal frequency of fast alternating hand and finger movements, simple reaction time and postural instability were recorded in healthy controls (n=18), patients with Parkinson’s disease (n=39) and essential tremor (n=37). Data were digitally converted and statistically analyzed. Results - Tremor intensity, median frequency and frequency distribution showed characteristic differences in the three groups. Performance in fast alternating movements of hands and fingers were significantly worse in both tremor groups compared to the healthy controls. Conclusions - The data also indicated that quantitative measurements of tremor parameters must be performed on both sides, because the presence of significant side differences support the diagnosis of Parkinson’s disease. The method presented can be used to objectively analyze tremor and performance in rhythmic movements. The results show that it helps to differentiate parkinsonian from essential tremor as well as to predict disease course and the effectiveness of therapy. Multivariate statistical analysis of tremor and movement performance also provides an opportunity to study the pathogenesis of human tremor.]

Clinical Neuroscience

[THE SIGNIFICANCE OF CHLAMYDIA PNEUMONIAE IN SELECTED NEUROLOGIC DISORDERS]

HORVÁTH Zoltán, VÉCSEI László

[Chlamydia pneumoniae has recently been implicated in the pathogenesis of several neurological diseases. As an intracellular parasite with its unusual life cycle it is able to circumvent the immune system and to persist in the organism. It has the ability to modify the function of the infected cell and supposedly induce autoimmune reactions. These properties can make it pathogenic in several chronic neurological diseases including multiple sclerosis, atherosclerosis, stroke, Alzheimer dementia and giant cell arteriitis. The evaluation of the available, often contradictory, data that are based on various different methods is not easy. The importance of the issue is enhanced by the potential need for antibiotic treatment.]

Clinical Neuroscience

[The potential role of spinal ketamine in multi-component antinociception]

JOÓ Gabriella

Clinical Neuroscience

[CONGRESS CALENDAR]

Clinical Neuroscience

[A NEURO-MECHANICAL TRANSDUCER MODEL FOR CONTROLLING JOINT ROTATIONS AND LIMB MOVEMENTS]

LACZKÓ József, KERRY Walton, RODOLFO Llinas

[Here we report on the development of an integrated general model for the control of limb movements. The model computes muscle forces and joint rotations as functions of activation signals from motoneuron pools. It models the relationship between neural signals, muscle forces and movement kinematics by taking into account how the discharge rates of motoneuron pools and the biomechanical characteristics of the musculoskeletal system affect the movement pattern that is produced. The lengths and inertial properties of limb segments, muscle attachment sites, the muscles’ force-length, force-frequency and force-velocity (of contraction) relationships, as well as a load parameter that simulates the effect of body weight are considered. There are a large number of possible ways to generate a planned joint rotation with muscle activation. We approach this “overcompleteness problem” by considering each joint to be controlled by a single flexor/extensor muscle pair and that only one of the two muscles is activated at a given time. Using this assumption, we have developed an inverse model that provides discharge rates of motoneuron pools that can produce an intended angular change in each joint. We studied the sensitivity of this inverse model to the muscle force-length relationship and to limb posture. The model could compute possible firing rates of motoneuron pools that would produce joint angle changes observed in rats during walking. It could also compare motoneuron activity patterns received for two different hypothetical force-length relations and show how the motoneuron pool activity would change if joints would be more flexed or extended during the entire movement.]

All articles in the issue

Related contents

Lege Artis Medicinae

[NON-INVASIVE CORONARY ANGIOGRAPHY BY MULTISLICE COMPUTED TOMOGRAPHY]

PRÉDA István, KERECSEN Gábor, MAUROVICH-HORVAT Pál

[This review summarizes the diagnostic spectrum, ways of application and methodological difficulties of multislice computed tomographic (MSCT) coronary angiography. The non-invasive assessment of cardiac and coronary anatomy is now possible with computed tomographic coronary angiography using the modern 16 to 64-slice technology. This technique finds its main use today in the screening of patients with moderate probability of having coronary artery disease (atypical chest pain). Its negative predictive value varies between 97% and 99%, thus, a negative result of this non-invasive outpatient procedure can reduce the possibility of coronary artery disease to the minimum. Other important diagnostic applications include the follow-up of patients with coronary artery bypass, accurate diagnosis of coronary artery anomalies, and the simultaneous examination of the heart and great vessels. The future development of the technique is directed to coronary plaque characterization, particularly the detection of vulnerable plaques. The radiation exposure is relatively low (7-13 mSv), comparable with that of invasive coronary angiography.]

Clinical Neuroscience

[Correction of the physiological artefacts at pre-surgical clinical functional MR]

KISS Máté, GÁL Andor Viktor, KOZÁK Lajos Rudolf, MARTOS János, NAGY Zoltán

[Introduction/aim of the study - Pre-surgical functional MRI (fMRI) is an important modality of examinations before brain surgery. There are several artefacts (e.g. motion, susceptibility) which may hinder the evaluation of fMRI data. Physiological artefacts (breathing, pulsation) also affect the sensitivity and specificity of anatomical localization. The aim of this study is to demonstrate the efficiency of physiological artefact identification and removal methods for presurgical evaluation. Materials and methods - Siemens Magnetom Verio 3T MRI scanner was used to collect data. The physiological parameters (breathing, pulse) were recorded with the MRI system’s built-in devices. Data from fourteen patients - with primary brain tumour - were evaluated with SPM12 utilizing the RETROICOR/RVHR tool to detect and decrease the effect of physiological artefacts. We compared the statistical maps obtained with and without the physiological correction using the Jaccard similarity coefficient, and ROI analyses. Results - Significant differences were found in the mean ROI values (p<0.0016) and the extensions of eloquent activations (p<0.0013), when using the physiological correction (RETORICOR/RVHR) based on convolution method. On the other hand, no significant differences were found between the ROIs’ standard deviations (F=0.28). The RETROICOR/ RVHR method helps to define the precise localisation of eloquent areas (p<0.009). The number of irrelevant (non-significant) voxels were increased (p<0.001). Conclusions - Minimising of physiological artefacts in fMRI data calculations, the (RETROICOR/RVHR) method based on convolution has been successfully adapted. This algorithm could be helpful before neurosurgical intervention. The activity pattern became more reliable. ]

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

[31th Congress of the Hungarian Pediatric Neurological, Neurosurgical, Pediatric and Adolescent Psychiatric Society]

NAGY Andrea

Lege Artis Medicinae

[Public health care prevention in Hungary: are we doing what we should?]

KISS István, DANKOVICS Gergely, BARNA István, DAIKI Tenno, KÉKES Ede

[Primary prevention means health protection and disease prevention in the population, whereas secondary prevention includes early diagnosis and treatment to prevent the progression of diseases and the development of complications. Both ways of prevention are present in public health programs, but primary prevention measures are usually less substantial. METHODS - The “Comprehensive Health Protection Screening Program of Hungary 2010-2020” was organised in 2010 as part of the National Cardiovascular Program. In this program, a mobile screening station (set up on a truck) tours the country and provides a complex health status and risk assessment at village fairs as well as at offices. RESULTS - In the past three years, this station provided complex screening for 65267 individuals and lifestyle counseling and health education for 132964 people at 528 locations, touring 58807 km. The aim of the Program is to provide a comprehensive overview of the health status of the Hungarian population, and to make it possible to measure and record the long-term changes of the health status of the Hungarian population. Another goal is to inform those being screened about their health status and to highlight the importance of health protection and disease prevention. On the basis of the results, in the past three years the Program has been able to achieve its targets, which provides a good basis for its continuation.]