Clinical Neuroscience

[Method for measuring the synchronization of EEG curves]

SZÉKELY József Iván1, SÁKI Péter1

APRIL 01, 1966

Clinical Neuroscience - 1966;19(04)

[Today, there are about half a dozen mathematical-statistical methods that allow a more precise and refined analysis of EEG curves than ever before. These methods, above all autocorrelation (Brazier and Casby, Brazier and Barlow), Fourier analysis (Dietsch, Hajtman and Dési) and the various averaging methods, are essentially analytical in nature. They break down the activity under study into its components according to given mathematical formulae and filter out the regular, the periodic and the average from the sea of random variations. We believe that an exhaustive and in-depth study of the electroencephalogram requires the use of all these methods, because each of them answers a different question and is based on a different mathematical principle. ]

AFFILIATIONS

  1. Budapesti Orvostudományi Egyetem Élettani Intézete és MTA Matematikai Kutató Intézet Biometriai Osztálya

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Further articles in this publication

Clinical Neuroscience

[Corticosteroid fractions in the human brain]

FAZEKAS I. Gyula, FAZEKAS Attila

[In cases of 1) pneumonia, 2) sudden death from cardiac arrest, 3) sudden death from cardiac arrest in an alcoholic state, and 4) vehicle hit-and-run hemorrhage or spinal cord rupture, extracts were obtained from 5 brain areas of 10 people aged 21-72 years 2-9 hours after death and subjected to paper chromatography in a Bush 5 system. The extracts were run with the following corticosteroids as standard : 1. tetrahydrocortisol, 2. tetrahydrocortisone, 3. cortisol (hydrocortisone), 4. cortisone, 5. corticosterone, 6. 11-dehydrocorticosterone - Brain areas studied : 1. bridge + rabbit brain, 2. cerebellum, 3. cerebellar peduncles, 4. cerebral cortex, 5. cerebral white matter. 1. a total of 11 steroid variants were detected, 6 of which were identical to the standards, the other 5 unidentified steroids were designated X, (Rf. 0.03), X2 (Rf. 0.06), X3 (Rf. 0.19), X4 (Rf. 0.66), X5 (Rf. 0.70). 2. These steroids were detected in different amounts and qualities in different brain areas depending on the deaths. 3. The highest amounts of cortisol (hydrocortisone) and corticosterone were detected. Other fractions were present in varying numbers and qualities in different brain areas. 4. Most of the fractions and the highest amounts were found in the brain areas of those who died of pneumonia. This was followed by the brain areas of those who died suddenly due to heart failure. In third place were the brain areas of those who died of cardiac paralysis in an alcoholic state and in fourth place, i.e. the fewest fractions and the smallest amount of fractions were found in the brain areas of those who died of an accident in an alcoholic state. 5. In agreement with the results of our previous animal studies, it was found that the number and amount of corticosteroid fractions in all areas of the human brain were significantly lower after alcohol compared to those in those who died of other causes. 6. No seemingly regular order in the total steroids in the brain areas of those who died of pneumonia could be established. 7. In those who died suddenly from heart failure and in the hemorrhagic case, most steroids were found in the area of the bridge + rabbit brain, second was the steroid content of the cerebellum, third was the brainstem, fourth was the cerebral cortex and fifth was the white matter of the cerebrum. Only in the case of rabbit brain laceration was the steroid content of the rabbit brain + bridge and cortex (presumably due to the lesions) lowest compared to the other three brain areas. 8. Further studies are needed to determine whether age, sex, and the time between death and examination (more than 10 hours) influence the amount, number and size of corticosteroid fractions in each brain area. ]

Clinical Neuroscience

[Methodology and place of gamma encephalography in neurological diagnosis]

PÁLVÖLGYI Richárd, HERNÁDY Tibor

[After a general physical introduction, the authors describe the methodology of gamma encephalography (GEG) with J131-labelled serum al bumin (RISA). After describing the advantages and disadvantages of the method, they discuss in detail the cases in which a reliable result can be expected from GEG. ]

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Evaluation of the effectiveness of transforaminal epidural steroid injection in far lateral lumbar disc herniations

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[Invasive investigations show that in two-thirds of patients the myocardial ischaemia persists without obstructive coronary disease and any other heart conditions (INOCA). The underlying cause may be microvascular dysfunction (CMD) with consecutive microvascular coronary disease (MVD) and microvascular or epicardial vasospastic angina (MVA). The modern practice of clinical cardiology while using the developed non-invasive cardiac imaging permits exact measuring of the coronary flow with its characteristic indices. All of these improve the diagnosing of CMD-induced myocardial ischemia and provide opportunity to determine primary MVD cases. Since the recognition and treatment of MVD is significantly underrep­resented in the Hungarian medical care, the primary stable microvascular angina (MVA) is described in detail below with its modern invasive and non-invasive differential diagnosis and treatment, concerning especially its frequency provoked by high blood pressure and female coronary heart diseases. There are highlighted all recommended diagnostic procedures available under domestic conditions.]

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[Second game, 37th move and Fourth game 78th move]

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[What has Go to do with making clinical decisions? One of the greatest intellectual challenges of bedside medicine is making decisions under uncertainty. Besides the psychological traps of traditionally intuitive and heuristic medical decision making, lack of information, scarce resources and characteristics of doctor-patient relationship contribute equally to this uncertainty. Formal, mathematical model based analysis of decisions used widely in developing clinical guidelines and in health technology assessment provides a good tool in theoretical terms to avoid pitfalls of intuitive decision making. Nevertheless it can be hardly used in individual situations and most physicians dislike it as well. This method, however, has its own limitations, especially while tailoring individual decisions, under inclusion of potential lack of input data used for calculations, or its large imprecision, and the low capability of the current mathematical models to represent the full complexity and variability of processes in complex systems. Nevertheless, clinical decision support systems can be helpful in the individual decision making of physicians if they are well integrated in the health information systems, and do not break down the physicians’ autonomy of making decisions. Classical decision support systems are knowledge based and rely on system of rules and problem specific algorithms. They are utilized widely from health administration to image processing. The current information revolution created the so-called artificial intelligence by machine learning methods, i.e. machines can learn indeed. This new generation of artificial intelligence is not based on particular system of rules but on neuronal networks teaching themselves by huge databases and general learning algorithms. This type of artificial intelligence outperforms humans already in certain fields like chess, Go, or aerial combat. Its development is full of challenges and threats, while it presents a technological breakthrough, which cannot be stopped and will transform our world. Its development and application has already started also in the healthcare. Health professionals must participate in this development to steer it into the right direction. Lee Sedol, 18-times Go world champion retired three years after his historical defeat from AlphaGo artificial intelligence, be­cause “Even if I become the No. 1, there is an entity that cannot be defeated”. It is our great luck that we do not need to compete or defeat it, we must ensure instead that it would be safe and trustworthy, and in collaboration with humans this entity would make healthcare more effective and efficient. ]

Clinical Neuroscience

A cross-sectional study on the quality of life in migraine and medication overuse headache in a Hungarian sample: understanding the effect of headache characteristics

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Previous studies using generic and disease specific instruments showed that both migraine and medication overuse headache are associated with lower health-related quality of life (HRQoL). The aim of our study was to assess HRQoL differences in migraineurs and in patients with MOH and to examine how headache characteristics such as years with headache, aura symptoms, triptan use, headache pain severity and headache frequency are related to HRQoL. In this cross-sectional study 334 participants were examined (248 were recruited from a tertiary headache centre and 86 via advertisements). The Comp­rehensive Headache-related Quality of life Questionnaire (CHQQ) was used to measure the participants’ HRQoL. Data showed normal distribution, therefore beside Chi-squared test parametric tests (e.g. independent samples t-test) were used with a two-tailed p<0.05 threshold. Linear regression models were used to determine the independent effects of sex, age, recruitment method, headache type (migraine vs. MOH) and headache characteristics (presence of aura symptoms, years with headache, headache pain severity, headache frequency and triptan use) separately for each domain and for the total score of CHQQ. Significance threshold was adopted to p0.0125 (0.05/4) to correct for multiple testing and avoid Type I error. Independent samples t-tests showed that patients with MOH had significantly lower scores on all CHQQ domains than migraineurs, except on the social subscale. Results of a series of regression analyses showed that triptan use was inversely related to all the domains of HRQoL after correction for multiple testing (p<0.0125). In addition, headache pain severity was associated with lower physical (p=0.001) and total scores (p=0.002) on CHQQ subscales. Based on the results, different headache characteristics (but not the headache type, namely migraine or MOH) were associated with lower levels of HRQoL in patients with headache. Determining which factors play significant role in the deterioration of HRQoL is important to adequately manage different patient populations and to guide public health policies regarding health service utilization and health-care costs.

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[Evaluation of clinical practices among academic nursing students]

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[Purpose: Establishing a balance between theoretical and practical training is essential in the training of college nursing students. The aim was to assess the students’ experiences of clinical practice and the problems they indicate in the component, which plays an important role in preparing the training for professional competencies. The study sample consisted of 3rd and 4th grade students (N=96) participating in nursing training at the Faculty of Health Sciences of Semmelweis University. The method of data collection was based on the completion of a quantitative online questionnaire, which also included qualitative elements in the form of three open-ended questions. Among the statements measured on the Likert scale, the balance of theory-practice, the role of participants in education, and the time spent on practical tasks received lower average ranks from both grades. Logistic regression is suitable for estimating the probability of a positive/negative impression of a practice as a combined effect of several explanatory variables. Compared to the results of a previous (2009) study, the problems with field clinical training remain unresolved.]