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Abstract Poor postural balance is one of the major risk factors for falling in normal pressure hydrocephalus (NPH). Postural instability in the clinic is commonly assessed based upon force platform posturography. In this study we focused on the identification of changes in sway characteristics while standing quiet in patients with NPH before and after shunt implantation. Postural sway area and sway radius were analyzed in a group of 9 patients and 46 controls of both genders. Subject's spontaneous sway was recorded while standing quiet on a force platform for 30-60 s, with eyes open and then closed. Both analyzed sway descriptors identified between-group differences and also an effect of shunt implantation in the NPH group. Sway radius and sway area in patients exhibited very high values compared with those in the control group. Importantly, the effect of eyesight in patients was not observed before shunt implantation and reappeared after the surgical treatment. The study documents that static force platform posturography may be a reliable measure of postural control improvement due to shunt surgery.

The aim of this study was to determine the time between the first detection of postural control impairments and the evident manifestation of ataxia in preclinical SCA1 individuals. Twenty five preclinical SCA1 mutation carriers: 13 with estimated disease onset ≤ 6 years (SCA1 +) aged 27.8 ± 8.1 years; 12 with expected disease onset > 6 years (SCA1-) aged 26.6 ± 3.1 years and 26 age and sex matched healthy controls (HCs) underwent static posturography during 5 years of observation. The movements of the centre of feet pressure (COP) during quiet standing with eyes open (EO) and closed (EC) were quantified by calculating the mean radius (R), developed surface area (A) and mean COP movement velocity (V). Ataxia was evaluated by use of the Scale for Assessment and Rating of Ataxia (SARA).SCA1 + exhibited significantly worse quality of stance with EC vs. SCA1- (p < 0.05 for V) and HCs (p < 0.001) even 5 to 6 years before estimated disease onset. There were no statistically significant differences between SCA1- and HCs. A slow increase in Cohen's d effect size was observed for V EO up to the clinical manifestation of ataxia. V EO and A EC recorded in preclinical SCA1 individuals correlated slightly but statistically significantly with SARA (r = 0.47).The study confirms that static posturography detects COP sway changes in SCA1 preclinical gene carriers even 5 to 6 years before estimated disease onset. The quantitative evaluation of stance in preclinical SCA is a sensitive biomarker for the monitoring of the disease progression and may be useful in clinical trials., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

A method was developed for the computerized volumetric assessment of the intracranial cerebrospinal fluid (CSF) distribution. The study involved 62 patients differentiated into two groups: with CSF resorption disorders (normal pressure hydrocephalus - 30 patients) and without CSF resorption disorders (various types of brain atrophy - 32 patients). The goal of the study was to ascertain whether the assessment, depending on the linear discriminant analysis of volumetric brain features, could be an effective tool differentiating the two groups. Volumetric measurements were performed using VisNow software. For each patient, five features were determined and subjected to discriminant analysis: CSF volume in the subarachnoid space and basal cisterns (SV), CSF volume in the intracranial ventricular system (VV), brain volume (BV), total intracranial CSF volume (FV), and total intracranial volume (TV). Discriminant analysis enables the achievement of a high percentage of correct classification of patients to the appropriate group determined on the result of a lumbar infusion test. The discriminator, based on three features: BV, SV, and VV, showed a complete separation of the groups; irrespective of age. The squared Mahalanobis distance was 70.8. The results confirmed the applicability of the volumetric method. Discriminant analysis seems a useful tool leading to the acquisition of a computer-aided method for the differential diagnosis of CSF resorption disorders.

Rheumatoid arthritis (RA) and osteoarthritis (OA) are common rheumatic diseases and account for a significant percentage of disability. Posturography is a method that assesses postural stability and quantitatively evaluates postural sways. The objective of this study was to estimate posturographic trajectories applying pattern recognition algorithms. To this end, k-nearest neighbors (k-NN) classifier was used to differentiate between healthy subjects and patients with OA and RA. The following parameters of trajectories were computed: radius of sways, developed area, total length, and two directional components of sways: length of left-right and forward-backward motions. Posturographic tests were applied with eyes open and closed, and with biofeedback control. We found that in RA, the radius of sways, the trajectory area, and the biofeedback coordination were related to the patients' condition. The trajectory dynamics in OA patients were smaller compared to those in RA patients. The smallest misclassification errors were observed after feature selection in the biofeedback test compared with the eyes open and closed tests. We conclude that the estimation of posturographic trajectory with k-NN classifier could be helpful in monitoring the condition of RA patients.

Introduction: A variety of diagnostic methods in normal pressure hydrocephalus and brain atrophy, it testifies to the difficulties in contrast to both teams. Develop a safe diagnostic tool having comparable statistical accuracy of the infusion test results would be of great clinical significance. The chances of implementing such a procedure in clinical practice, it may be a combination of these syndromes in the functional assessment (Posturography) the assessment of morphological CNS (volumetric)., The Aim: To evaluate and summary of the results of two non-invasive diagnostic methods morphological (posturography) and functional (volumetric) with results that were obtained from tests infusion., Material and Methods: The evaluation of volumetric and posturographic research was conducted in 39 patients including 27 patients with brain atrophy (BA) and in 12 patients with hydrocephalus (NPH). Volumetric measurements were made using proprietary software VisNow. Posturographic measurements performed using manual posturograph Pro-Med., Results: Both the volume of CSF obtained by volumetric assessment, as well as the values of the analyzed parameters posturographic, highly correlate with the results of resistance resorption (R). The BA radius values sway with eyes open and closed R&#95;OZ R&#95;OO were consistent with test results infusion of 100% in the NPH radius values showed 75% compliance with the test results infusion. Volumetric parameters: the volume of CSF contained in the subarachnoid space and basal cisterns (SV) and the volume of CSF system intracranial ventricular (VV) were found in both patients NPH and BA 100% compatible resorption resistance (R)., Conclusions: Simultaneous use of two non-standard methods of non-invasive (posturographic and volumetric) in the diagnostic process is a proposal to recognize normal pressure hydrocephalus and brain atrophy non-invasive methods, while maintaining very high statistical significance.

Unlabelled: Clinical symptomatology of idiopathic normal pressure hydrocephalus, due to its overlap with dementias and neurodegenerative brain disorders, makes diagnosis challenging. As the neurological deficits are reversible there is a need for prompt and reliable noninvasive testing. The aim was to try to use and introduction into clinical practice of new non-invasive method--diffusion tensor imaging (DTI-Diffusion Tensor Imaging) discriminating patients classified as normal pressure hydrocephalus and patients diagnosed with brain atrophy., Material and Methods: Using magnetic resonance-diffusion tensor imaging, we examined white matter changes within the brains of patients diagnosed with idiopathic normal pressure hydrocephalus, cerebral atrophy and controls. Diffusion tensor brain images were obtained with 3Tesla and 1.5 Tesla MR-scanners. Fractional anisotropy brain maps were generated using a computer-automated method, and tract-based spatial statistics were then applied to compare the fractional anisotropy values in the clinical groups. The fractional anisotropy data were further investigated using region-of- interest analysis set within: fibre commissural the lateral ventricles (Fclv), forceps minor of corpus callosum (Fmin), cingulum (Cg), optic radiation (Orad), superior cerebellarpeduncle (Scp), substantia nigra (nucleus ruber) (Sn)., Results: Compared with the cerebral atrophy or control group, the FA values in the hydrocephalus group were significantly different in the posterior cingulate (Cg) and the forceps minor of the corpus callosum (Fmin)., Conclusion: The pattern of white matter tracts changes in select brain regions distinguishes it from cerebral atrophy and control brains. Our pilot study adds to the body of knowledge advancing the understanding of the white matter pathology of idiopathic normal- pressure hydrocephalus.

Differentiation between normal pressure hydrocephalus (NPH) and brain atrophy is difficult in clinical practice. The purpose of this paper was to apply two advanced statistical, pattern recognition methods: discriminant analysis (DA) and k-nearest neighbour (K-NN) for the classification of NPH and atrophy patients to approach computer aided differential diagnosis. The classification is based on a few measures of the center of foot pressure (COP) movements (radius, area, and length). The posturography method gives a measure of current postural stability by a quantitative evaluation of postural sways. Measurements have been performed in the standing upright position in two conditions: with eyes open (EO) and closed (EC). The study comprises 18 patients (mean age 64 ±13 years) diagnosed as normal pressure hydrocephalus and qualifying for shunt implantation. The patients were evaluated by static posturography twice: before and after surgery. The NPH patients were compared with 36 atrophy patients (mean age 64±13 years) and 47 healthy persons (mean age 60 ±7 years). There were two basic dissimilarities in the NPH patients before surgery in comparison with the other groups: very large sways and their independence from vision. Over 90% of the NPH cases both before and after surgery were correctly classified. There also were over 90% of correctly classified patients if we compared the before surgery NPH and atrophy patients. Further posturographic measurements and data collection are needed to verify these results.

Background and Purpose: This study aimed to quantitatively evaluate balance disturbances by means of static posturography in patients with enlargement of the ventricular system (Evans ratio > 0.3)., Material and Methods: Fifty-four patients were diagnosed and treated in our Department of Neurosurgery. Thirty-six of them were qualified as patients with brain atrophy and 18 others were identified as patients with normal pressure hydrocephalus (NPH). Average sway radius and developed area of the posturogram were evaluated with eyes open and closed. These parameters constituted a base to calculate vision indices related to radius and area as a result of division of the difference of a given parameter (radius or area) measured with eyes closed and open by its corresponding sum., Results: The sway range was significantly greater in patients with NPH in comparison to the control group. In NPH, there were no differences of sways observed with eyes open or closed - the vision indices were not statistically different from zero (vision index related to radius: -6.1 ± 18.9%, vision index related to area: -5.1 ± 34.7%). This may indicate no participation of sight in postural stability control. Values of the vision index related to radius (9.3 ± 19.4%) and to area (22.1 ± 28.2%) in the atrophy group significantly differed from zero, which indicated the participation of sight in postural stability control., Conclusions: Introduction of a new measure called the 'vision index' seems to be a promising clinical practice method of differentiation of hydrocephalus and brain atrophy.

Gait and body balance disturbances are important clinical problems in patients with normal pressure hydrocephalus (NPH). They affect patients' locomotion and lead to a higher risk of falls. The gait pattern may be described as durations of the single and double support and of a stance phase. The aim of the present study was to apply the pattern recognition methods for the evaluation of gait disturbances in patients with NPH before and after neurosurgical treatment (shunt implantation). The results indicate that the parameters measured with a Computer DynoGraphy (CDG) system may effectively differentiate changes of gait in patients with NPH.

Disturbances of gait and balance are important clinical problems in patients with normal pressure hydrocephalus. A considerable degree of locomotor disability and increased risk of falls are present in many cases. Accordingly, attempts to develop effective evaluation methods of gait and balance disturbances are made. Posturography and the Computer Dyno Graphy (CDG) system appear to be useful in diagnosis and evaluation of treatment in patients with normal pressure hydrocephalus. Both are non-invasive and repeatable methods that enable accurate evaluation of analyzed parameters at time intervals.

The aim of this paper was to characterize structural balance of the body in people with systemic vertigo after applying rehabilitation exercise, such as motor-visual coordination on a posturographic platform and balance exercise. Physiotherapeutic procedures were carried out in a group of 12 people, aged 25-60 years suffering from vertigo. The evaluation of body balance in the standing position was performed by means of recording of postural sways based on force-plate posturography. The examination was performed before and after the rehabilitation program. Standard tests were done, with eyes open, eyes closed, and with conscious visual control-biofeedback. Patients with vertigo underwent a month-long therapy, which included: exercise of motor-visual coordination on a posturographic platform and balance exercise, which consisted of repeated visual, vestibular, and somatosensory stimulation for conscious postural control. The rehabilitation program resulted in a decrease of the range of sways, improved visuomotor coordination and thus also improved balance.

Standard measures of sleep recordings give differing results depending on the gender and they constantly change with age. Sleep latency increases, delta sleep decreases, and sleep tend to be shorter in duration and fragmented in middle-aged and elderly adults. The deterioration of sleep is observed earlier in men. In the 1980s, new measures called the Latency of Eye Movement (LEM) and the Mean Latency of Eye Movement (M-LEM) were proposed. Previous studies have shown that untreated patients with endogenous depression had the LEM and M-LEM shortened and that both indices get prolonged during treatment with antidepressants. On the other side, alcoholics in the abstinence period have LEM and M-LEM twice as long as healthy controls. In this study we set out to compare LEM and M-LEM in healthy humans according to the gender and age. The subjects of the study were 80 healthy volunteers: 40 males and 40 females, who were divided into 4 groups: females and males, below and above 40 years of age. In contrast to standard measures, our study did not reveal any significant changes of LEM or M-LEM due to the gender or age.

Aims: In patients with acute myocardial infarction (MI), low serum triiodothyronine (T3) concentration is commonly associated with a severe clinical course. The aim of this prospective study was to investigate whether a severe clinical course in patients with low T3 is related to the magnitude of myocardial injury assessed by echocardiography., Methods and Results: Out of 635 patients with MI we enrolled 100 consecutive patients. They were divided in two subgroups: group A, 81 patients without clinical hard events (death, resuscitation following ventricular tachycardia/vertricular fibrillation, new MI) and group B, 19 patients in whom at least one of the above hard events occurred during hospital stay. Thyroid function tests were performed on day 1, 4 and 7, echocardiographic examinations measuring asynergic area (AA), and wall motion score index (WMSI) between day 1 and 5 (median 3). A negative correlation was found between plasma free triiodothyronine (FT3), concentration and AA (p<0.001), FT3 and WMSI (p<0.001) values at all time points. FT3 concentration was lower in group B than group A at all time points (p<0.001)., Conclusions: In patients with acute MI, low FT3 state is related to the extent of myocardial damage.

Somatosensory evoked potentials from median nerve (SEP-M) were examined bilaterally in 43 patients with a well delimited vascular foci in central somatosensory pathways. Scalp, far field, cervical, Erb potentials and conduction times were recorded in each patients. Five subgroups based on localization of foci (parietal cortex, corona radiata, internal capsule, thalamus and extensive subcortical--cortical hemispheric focus) were distinguished. The results from the unimpaired (n-38) and impaired (n-48) sides, focus subgroups and control healthy group were statistically compared. The attempt to establish a specific relationship between the SEP-M picture and site of the lesion gave a negative result. SEP-M changes were more pronounced in cases of very extensive axons run in a compact bundle (internal capsule). The SEP-M examination indicates only the degree of the central sensory system damage. Correlations between intensity SEP-M pathology and clinical sensory disturbances were found. SEP-M parameters on the unimpaired side differed significantly from those of the control group. Therefore the impaired side should not be used as a reference for evaluation of impaired side pathology. The diagnostic validity of far field potentials recordings in such investigations is stressed.

The computer analysis of the dynamics of volleys is proposed by means of the so-called pattern function (template), which describes the change of time-intervals between spikes inside volleys. The validation of the proposed method is based on the analysis of artificially generated volleys.

A program for automatic evaluation of EEG spectra, providing considerable reduction of data, was devised. Artefacts were eliminated in two steps: first, the longer duration eye movement artefacts were removed by a fast and simple 'moving integral' methods, then occasional spikes were identified by means of a detection function defined in the formalism of the autoregressive (AR) model. The evaluation of power spectra was performed by means of an FFT and autoregressive representation, which made possible the comparison of both methods. The spectra obtained by means of the AR model had much smaller statistical fluctuations and better resolution, enabling us to follow the time changes of the EEG pattern. Another advantage of the autoregressive approach was the parametric description of the signal. This last property appeared to be essential in distinguishing the changes in the EEG pattern. In a drug study the application of the coefficients of the AR model as input parameters in the discriminant analysis, instead of arbitrary chosen frequency bands, brought a significant improvement in distinguishing the effects of the medication. The favourable properties of the AR model are connected with the fact that the above approach fulfils the maximum entropy principle. This means that the method describes in a maximally consistent way the available information and is free from additional assumptions, which is not the case for the FFT estimate.

The analysis of the electrical activity (trains of spikes, volleys) of single neurons is proposed in form of a pattern function. From the pattern function and its variance it is possible to obtain full statistical description of volleys including the density distribution of spikes in the volley. An algorithm for finding the pattern function and the estimate of variance from a set of experimentally obtained volleys is given. Preliminary physiological conclusions for phrenic motoneurons are derived.

The authors present the principles of work of a computer system destined for evaluation of the results of routine electrophysiological examination of two muscles and four sensory nerves in alcohol-dependent subjects. The range of examinations and the programme based on discrimination analysis make possible, as shown in own investigations, an objective and complete evaluation of the state of the peripheral nervous system in these subjects. The programme is owned by the EMG laboratory of the Institute of Psychiatry and Neurology in Warsaw where it was introduced for clinical diagnosis, but it may be made available to other persons interested in these problems. An electromyograph with a stimulator with current exit averager and minicomputer, e.g. Commodore 64 with a printer are necessary.