Clinical Neuroscience

[BIOMECHANICS OF INTRACRANIAL ANEURYSMS]

FARKAS István, NYÁRY István, RAFFAI Gábor, ZILAHY G, MONOS Emil

NOVEMBER 30, 2006

Clinical Neuroscience - 2006;59(11-12)

[Introduction - Viscoelastic parameters of circumferential and meridional strips of ruptured and silent aneurysms were investigated (considered clinical and histological data either) in order to advance the prediction of risk of aneurysm rupture. Method - In our clinical practice, aneurysms managed by microsurgery aneurysm clipping were removed. Meridional and circumferential strips were cut. Strips were investigated by an uniaxial biomechanical instrument: distending force was recorded as the length of the strips was increased in steps. Normal stress-relaxation patterns were detected. The shape of strain curves well overlapped with the Standard Linear Solid Model curve, as had been expected. The viscosity, serial and parallel elastic moduli of the model were then computed. Results - Linear correlation was demonstrated amongst peek distending force detected and aneurysm strip thickness. Steric inhomogenity was detected at the meridional and circumferential strips. Strain-stress behaviour of ruptured and silent aneurysm specimen showed significant difference. Values of strips originated from patients suffered from hypertension as well as strips originated from aneurysms had been histologically found inflamed were higher. Discussion - Results of these observations are going to be used to set three dimensional computer model in cooperation with IT team of Budapest University of Technology and Economics to advance rupture risk prediction.]

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Clinical Neuroscience

[THORACIC MENINGOCELE]

FEKETE Tamás Fülöp, VERES Róbert, NYÁRY István

[Herniation of the meninges through a defect of the spinal canal is a spinal meningocele, and is usually located dorsally in the lumbosacral region. Meningoceles are usually part of a complex developmental disorder, or of a systemic disease, or it can be iatrogenic, as well. We report a very rare case of a true anterior thoracic meningocele.]

Clinical Neuroscience

[MOVEMENT-RELATED BETA RESPONSES IN ESSENTIAL TREMOR AND PARKINSON’S DISEASE]

GERTRÚD Tamás, PÁLVÖLGYI László, TAKÁTS Annamária, SZIRMAI Imre, KAMONDI Anita

[Objective - To investigate the pathomechanism of essential (ET) and parkinsonian tremor (PT) by studying the correlation between tremor severity and movement-related beta rhythm changes of the human electroencephalogram. Patients and methods - We recorded the electroencephalogram of 10 patients with essential tremor, 10 with Parkinsonian tremor and 10 controls. In a preliminary session we determined the side with lower and higher tremor intensity (T+, T++ respectively), using accelerometry. Subjects pressed an on-off switch in a self-paced manner with left and right thumb. After digitalization of the EEG from Cz, C3, C4 electrodes, the movement reactive beta frequency (MRBF), its minimum/maximum peak power values and their latencies triggered to movement offset were determined. Results - The time course and amplitude of movement related beta desynchronization (ERD) were similar in each group regardless of tremor intensity. In ET tremor severity did not influence post-movement beta synchronization (PMBS) amplitude (PMBSET+=100.98±48.874%, PMBSET++=135.1±92.87%; p=0.231), however it was significantly delayed after the movement of the more tremulous hand (latPMBSET+=1.26±0.566 s, latPMBSET++= 1.57±0.565 s, p=0.003). In the PT group on the side of pronounced tremor the amplitude of PMBS decreased but it was not delayed, compared to the less affected hand (PMBSPT+=115.19±72.131%, PMBSPT++= 77.84±53.101%, p=0.0028; latPMBSPT+=1.4±0.74 s, latPMBSPT++=1.25±0.797 s, p=0.191). In controls the power and latency of PMBS was similar on both sides. Conclusions - The results suggest that neuronal mechanisms underlying PMBS generation are differently affected by ET and PT. Investigation of PMBS might be used for the differential diagnosis of essential tremor and Parkinson's disease.]

Clinical Neuroscience

[THE ROLE OF TREMOROMETRY IN PREDICTING THE OUTCOME OF ABLATIVE SURGERIES]

KOVÁCS Norbert, BALÁS István, ILLÉS Zsolt, KELLÉNYI Lóránt, NAGY Ferenc

[Ablative neurosurgical interventions are widely used for the treatment of advanced Parkinson's disease. However, in some cases, the achieved result is temporary and repeat operation is necessary to obtain a permanent effect. By analyzing 30 ablative surgeries using comparative accelerometry, we looked for a biological marker predicting the efficiency. In 27 cases where clinical symptoms were permanently improved, a significant increase in rest tremor frequency was observed in addition to reduction in tremor intensity. In contrast, in those three cases where the clinical effect of the surgery was only temporary, the frequency of tremor remained unchanged despite of the transitory decrease in intensity. We thus hypothesize that postoperative change in frequency of tremor but not the intensity may predict the outcome of ablative treatments.]

Clinical Neuroscience

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Clinical Neuroscience

[LONG-TERM APPLICATION OF THE MULTIPLE SCLEROSIS FUNCTIONAL COMPOSITE IN DEBRECEN]

MEZEI Zsolt, BERECZKI Dániel, CSIBA László, CSÉPÁNY Tünde

[Introducion - The multiple sclerosis functional composite (MSFC) has been recommended by the National Multiple Sclerosis Society as a new clinical outcome measure. It is based on measurements in three clinical dimensions: leg function/ambulation (timed 25-foot walk), arm function (9 hole peg test) and cognitive function (paced auditory serial addition test). Scores on component measures are converted to standard scores (Z-scores), that reflect patient performance. This method has not yet been introduced into routine clinical practice. Patients and methods - Since March 2000 over the five years period the MSFC calculation was applied to 17 patients with relapsing-remitting multiple sclerosis (age mean: 37.4±10.8 years, duration of the disease: 5.5±4.9 years, EDSS: 2.7±1.4) seen at the neuroimmunological outpatient clinic to evaluate its usefulness and its correlation with the traditionally applied expanded disability status scale (EDSS). Thirteen patients received immunomodulatory treatment (interferon beta and glatiramer acetate), one patient received immunosuppressant therapy (azathioprine), and there was a patient, to whom developed secondary - progressive phase and we changed the interferon treatment to mitoxantrone. MSFC and EDSS were measured at 3., 6., 9, 12., 18 and 60 months of follow-up. Results - The prospective study confirmed a strong correlation between EDSS and MSFC in multiple sclerosis. The MSFC was more sensitive to clinical changes than EDSS. Our results after 18 months of follow up are already published. After five years arm/hand function and leg function/ambulation were the most sensitive mesures for disease progression. In contrast with the literature we did not experience correlation with cognitive changes. Consequences - We demonstrated strong correlation between MSFC and EDSS after a longer period. MSFC is a simple method, suitable for follow-up of multiple sclerosis patients in everyday clinical practice.]

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Clinical Neuroscience

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