Clinical Neuroscience

[EEG-based cerebral networks in 14 neurological disorders]

DÖMÖTÖR Johanna, CLEMENS Béla, CSÉPÁNY Tünde, EMRI Miklós, FOGARASI András, HOLLÓDY Katalin, PUSKÁS Szilvia, FEKETE Klára, KOVÁCS Attila, FEKETE István

MAY 30, 2017

Clinical Neuroscience - 2017;70(05-06)

DOI: https://doi.org/10.18071/isz.70.0159

[Background - Brain networks have not been systematically investigated yet in most neurological disorders. Purpose - To investigate EEG functional connectivity (EEGfC) networks in 14 neurological disorders. Patients - Potentially eligible patients were collected from clinical and EEG databases. All the available clinical data and EEG records were critically revised. All the patients who suffered of a single neurological disorder (out of the 14) and had a good quality EEG recording entered the study. Confoundig factors as comorbidity and CNS-active drug effects were eliminated as far as possible. EEG analysis - Three minutes of resting-state, waking EEG activity were selected for analysis. Current source density (CSD) values were computed for 2394 cortical voxels by Low Resolution Electromagnetic Tomography (LORETA). Thereafter, Pearson correlation coefficients were computed between all pairs of 23 cortical regions of interest (ROI) in each hemisphere (LORETA Source Correlation, LSC software). Computation was carried out for conventional EEG broad bands and very narrow bands (1 Hz bandwidth) between 1 and 25 Hz as well. Correlation coefficients of each group were statistically compared to our normative EEG (LSC) database by two-talied t-tests. Bonferroni-corrected p<0.05 values were accepted as statistically significant, and were graphically displayed as topographical networks. Results and conclusion - Group-specific networks were demonstrated. However, non-specific networks, charasteristic for most groups, were detected as well. Common finding were: decreased connectivity in the alpha band and increased connectivity in the delta, theta bands and upper-beta band. Decreased alpha-band connectivity presumably reflected primary lesional effects and on the other hand, non-specific vulnerability of “rich club connections”. Increased connectivity in the slow bands presumably indicated adaptive-compensatory activity of brain homeostasis. ]

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[Prevention of invasive meningococcal infection, recognition and first treatment of the disease in primary care]

KOVÁCS Ákos, KULCSÁR Andrea, KALABAY László, TORZSA Péter

[Neisseria meningitidis, the meningococcus, is a Gram-negative diplococcal bacterium that is only found naturally in humans. The meningococcus is part of the normal microbiota of the human nasopharynx and is commonly carried in healthy individuals. In some cases systemic invasion occurs, which can lead to meningitis and/or septicemia. Invasive disease caused by Neisseria meningitidis is potentially devastating, with a high case fatality rate and high rates of significant sequelae among survivors after septicaemia or meningitis. Between 2006-2015 every year between 34 and 70 were the numbers of the registered invasive disease because of Neisseria meningitis, the morbidity rate was 0.2-0.7⁰⁄₀₀₀₀. Half of the diseases (50.7%) were caused by B serotype N. meningitidis, 23.2% were C serotype. In this article the authors summarise what you must do and must not do as primary care physician when suddenly meeting a young patients suspected of having meningococcus infection. ]

Clinical Neuroscience

[Experience with natalizumab-treatment at Semmelweis University]

GOMBOS Barbara, ILJICSOV Anna, BARSI Péter, HEGEDÛS Katalin, SIMÓ Magdolna

[Multiple sclerosis is an autoimmune demyelinating disorder of the central nervous system. During the last two decades, numerous disease modifying drugs have been introduced for the treatment of the relapsing-remitting form of the disease. Since 2010, natalizumab (NTZ) treatment has been used as a second-line therapy for patients with breakthrough disease. In comparison to conventional immunomodulant drugs, NTZ has a more specific effect in that it prevents the entry of immune cells into the central nervous system without interfering with systemic immune response. The efficacy and the safety of NTZ have been confirmed by several studies. The most severe side-effect of NTZ is progressive multifocal leukoencephalopathy, which has been associated with an increased incidence in patients with anti-JCV antibody positivity, and in those who have been undergoing NTZ treatment for over two years and who have received prior immunosuppressive therapy. In the present study, our experience with natalizumab treatment of 37 patients at the Department of Neurology of Semmelweis University during the last 6 years is presented. We have observed a significant decrease of disease activity in our patients; in many cases the disease has become inactive both clinically (36/37) and radiologically (34/37). The patients’ quality of life has improved significantly during the treatment. In accordance with the literature, we confirm that NTZ is a highly effective treatment in a carefully selected patient group, and can be administered without significant inconvenience to the patient. ]

Clinical Neuroscience

The role of the insula in the parieto-frontomedial epileptic network. Clues from successful surgical treatment

BALOGH Attila, AIMEN Anwar, KELEMEN Anna, ERÕSS Loránd, FABÓ Dániel

We present a case of MRI negative SMA seizure with the seizure onset zone in the secondary leg area on the superior bank of the Sylvian fissure, localized with multiscale electro-clinical and neuroradiological examinations. The 34-year-old female patient’s intractable epilepsy started at age 14. She had diffuse pain aura in her left leg followed by tonic posturing with fully preserved consciousness suggesting parieto-fronto-medial seizure propagation. Her daily nocturnal SMA seizures became drug-resistant. Multiple 3T MRI images and neuropsychological evaluations were normal. Interictal PET detected a right parietal and insular FDG hypometabolism. The seizure onset zone and the symptomatogenic zone were localized by invasive electrophysiology. The insular deep electrode showed the propagation of ictal activity with an onset in the secondary sensory leg area through the insula to the fronto-medial surface. Eighteen spontaneous seizures, electrical cortical stimulation and cortical mapping confirmed the designated area of the resection, which was later proved macroscopically abnormal during surgery. The histological and immunohistological workup confirmed focal cortical dysplasia (IIb type). Postoperative postprocessing morphometry of the preoperative MRI study confirmed the lesion in the right inferior parietal lobe. The patient remained seizure free after surgery for more than 4 years, and medication free for the last two years. Our results concluded that the insula has a „relay” or „node” function in the parieto-opercular-fronto-medial epileptic network. The insular functional connectivity predisposed frontal propagation of the epileptic activity in the connectome of her epilepsy. The three-way insular structural connectivity has determining function on the seizure propagation.

Clinical Neuroscience

Case report of a woman with anti amphiphysin positive stiff person syndrome

MANHALTER Nóra, GYÖRFI Orsolya, BOROS Erzsébet, BOKOR Magdolna, FAZEKAS Ferenc, DÉNES Zoltán, FABÓ Dániel, KAMONDI Anita, ERÕSS Loránd

Stiff person syndrome is a rare neuroimmunological disease, characterized by severe, involuntary stiffness with superimposed painful muscle spasms, which are worsened by external stimuli. The classical form is associated with high levels of antibodies against glutamic acid decarboxylase. One of the variant forms is associated with antibodies against amphiphysin. This entity is a paraneoplastic syndrome, caused primarily by breast cancer, secondarily by lung cancer. Symptomatic therapy of anti amphiphysin positive stiff person syndrome includes treatment with benzodiazepines and baclofen (including intrathecal baclofen therapy). The effect of immunological therapies is controversial. Treatment of the underlying cancer may be very effective. In this report, we describe a 68 year old female presenting with an unusally rapidly developing anti amphiphysin positive stiff person syndrome, which was associated with breast cancer. Her painful spasms abolished after intrathecal baclofen treatment was initiated. Her condition improved spontaneously and significantly after cancer treatment, which enabled to start her complex rehabilitation and the simultaneous dose reduction of the intrathecal baclofen. The bedridden patient improved to using a rollator walker and the baclofen pump could be removed 18 monthes after breast surgery. This highlights the importance of cancer screening and treatment in anti amphiphysin positive stiff person syndrome cases.

Clinical Neuroscience

[Relationship between the number of hours of sunshine and the number of (violent) suicides in Hungary]

BOZSONYI Károly, ZONDA Tamás, FÜLÖP Andrea, BÁLINT Lajos

[Aim - Studying the impact of the sunshine on the numbers of suicides. The number of suicides is highest in the late spring and early summer months, while it is lowest in the cold, gloomy winter. Although the exact causes are still un-known, there are some theories about this phenomenon. A number of studies conducted in recent years have conclud-ed that the rise in suicide rate during the warm months might be due to an increased exposure to sunlight, especially in the cases of the violent method. We studied the validity of this hypothesis on a large Hungarian database. Methods and subjects - We analyzed the number of monthly hours of sunshine and the number of suicides by sex and by violent vs. non-violent method over a 360-month period. Our sample consisted of 127 877 committed suicides between 1971 and 2000. The parabolic trend of seasonality had to be removed from the suicide time series, then regression analysis was conducted on the seasonally adjusted data. Results - Our analysis revealed that in Hungary there was no statistically significant direct relationship between the number of hours of sunshine and the number of suicides. Moreover, there was no correlation between the hours of sunshine and the number of violent suicides either. Conclusion - If the above claim were confirmed in subsequent research, it would mean that our current therapeutic regime should be reconsidered during the spring-summer seasons.]

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