Instrumental and Non-Instrumental Measurements in Patients with Peripheral Vestibular Dysfunctions.

Vestibular dysfunction is a disturbance of the body's balance system. The control of balance and gait has a particular influence on the quality of life. Currently, assessing patients with these problems is mainly subjective. New assessment options using wearables may provide complementary and more objective information. Posturography makes it possible to determine the extent and type of posture dysfunction, which makes it possible to plan and monitor the effectiveness of physical rehabilitation therapy. This study evaluates the effectiveness of non-instrumental clinical tests and the instrumental mobile posturography MediPost device for patients with unilateral vestibular disorders. The study group included 40 patients. A subjective description of the symptoms was evaluated using a questionnaire about the intensity of dizziness using the Dizziness Handicap Inventory (DHI) and Vertigo Syndrome Scale-short form (VSS-sf). The clinical protocol contained clinical tests and MediPost measurements using a Modified Clinical Test of Sensory Interaction on Balance. All patients underwent vestibular rehabilitation therapy (VRT) for four weeks. The non-instrumental measurement results were statistically significant, and the best was in the Timed Up and Go test (TUG). In MediPost, condition 4 was the most valuable. This research demonstrated the possibilities of using an instrumental test (MediPost) as an alternative method to assess balance.

Innovative System for Evaluation and Rehabilitation of Human Imbalance.

<b>Introduction:</b> Mobile posturography is based on wearable inertial sensors; it allows to test static stability (static posturography) and gait disturbances. </br> </br> <b>Aim:</b> The aim of this work was to present the results of research on the innovative MEDIPOST system used for diagnosis and rehabilitation of balance disorders. </br> </br> <b>Material and methods:</b> Fourteen articles published in influenced foreign journals were presented and discussed. The deve-lopment and construction of the device was preceded by a literature review and methodological work. The Dizziness Handi-cap Inventory (DHI) questionnaire was translated and validated. The methodology of posturography with head movements with a frequency of 0.3 Hz was also developed in the group with chronic vestibular disorders. Simultaneous measurements were performed (static posturogrphy vs. MEDIPOST) in the CTSIB-M (Modified Clinical Test of Sensory Interaction in Balance) test in healthy subjects and patients with unilateral peripheral dysfunction.</br> </br> <b>Results:</b> In the posturography with head movements the improvement of sensitivity (67 to 74%) and specificity (65 to 71%) was noted. In the CTSIB-M test the intraclass correlation coefficients for both methods were 0.9. The greatest differences between examinations were observed for the mean angular velocity in the tests on the foam (trials no. 3 and 4), in particular on the foam with eyes closed (trial no. 4 - sensitivity 86.4%, specificity 87.7%). Two functional tests were analyzed: the Swap Seats test and the 360 degree turn test. In the former, the results are studied from 6 sensors - 86% of the true positives and 73% of the true negatives for the fall/ no-fall group classification. The second test differentiates people with vestibular impairment and healthy people. It can be analyzed with 1 (sensitivity 80%) and 6 sensors (sensitivity 86%, specificity 84%). Currently, the MEDIPOST device is in the development and certification phase.

Detection of balance disorders using rotations around vertical axis and an artificial neural network.

Vestibular impairments affect patients' movements and can result in difficulties with daily life activities. The main aim of this study is to answer the question whether a simple and short test such as rotation about a vertical axis can be an objective method of assessing balance dysfunction in patients with unilateral vestibular impairments. A 360˚ rotation test was performed using six MediPost devices. The analysis was performed in three ways: (1) the analytical approach based only on data from one sensor; (2) the analytical approach based on data from six sensors; (3) the artificial neural network (ANN) approach based on data from six sensors. For approaches 1 and 2 best results were obtained using maximum angular velocities (MAV) of rotation and rotation duration (RD), while approach 3 used 11 different features. The following sensitivities and specificities were achieved: for approach 1: MAV-80% and 60%, RD-69% and 74%; for approach 2: 61% and 85% and RD-74% and 56%; for approach 3: 88% and 84%. The ANN-based six-sensor approach revealed the best sensitivity and specificity among parameters studied, however one-sensor approach might be a simple screening test used e.g. for rehabilitation purposes.

Utility of the Novel MediPost Mobile Posturography Device in the Assessment of Patients with a Unilateral Vestibular Disorder.

Balance disorders are a growing problem worldwide. Thus, there is an increasing need to provide an inexpensive and feasible alternative to standard posturographic platforms (SP) used for the assessment of balance and to provide a possible solution for telemonitoring of patients. A novel mobile posturography (MP) MediPost device was developed to address these issues. This prospective study used a Modified Clinical Test of Sensory Interaction on Balance to evaluate healthy individuals and patients with a unilateral vestibular disorder through SP and MP simultaneously. The control group included 65 healthy volunteers, while the study group included 38 patients diagnosed with a unilateral vestibular deficit. The angular velocity values obtained from both methods were compared by intraclass correlation coefficients (ICC) and Bland−Altman plot analysis. Diagnostic capabilities were measured in terms of sensitivity and specificity. The ICC between the two methods for conditions 2−4 was indicative of excellent reliability, with the ICC > 0.9 (p < 0.001), except for Condition 1 (standing stance, eyes open) ICC = 0.685, p < 0.001, which is indicative of moderate reliability. ROC curve analysis of angular velocity for condition 4 represents the most accurate differentiating factor with AUC values of 0.939 for SP and 0.953 for MP. This condition also reported the highest sensitivity, specificity, PPV, and NPV values with 86.4%, 87.7%, 80%, and 90.5% for SP, and 92.1%, 84.6%, 77.8%, and 94.8% for MP, respectively. The newly developed MediPost device has high sensitivity and specificity in distinguishing between healthy individuals and patients with a unilateral vestibular deficit.

A comparison of head movements tests in force plate and accelerometer based posturography in patients with balance problems due to vestibular dysfunction.

This study compares HS posturography on inertial sensors (MediPost) with force platform posturography in patients with unilateral vestibular dysfunction. The study group included 38 patients (age 50.6; SD 11.6) with unilateral vestibular weakness (UV) and 65 healthy volunteers (48.7; SD 11.5). HS tests were performed simultaneously on the force plate and with MediPost sensor attached at L4. Four conditions applied: eyes open/closed, firm/foam. The tests were performed twice, with the head moving at the frequency of 0.3 Hz (HS 0.3) and 0.6 Hz (HS 0.6). Mean sway velocity was significantly lower for MediPost than force plate in 4th condition both in UV and healthy group. For HS 0.3 the differences between devices were marginal; the highest sensitivity (87%) and specificity (95%) were in 4th condition. For HS 0.6 MediPost revealed lower sensitivity than force plate although the surface parameter improved results. MediPost IMU device and force platform posturography revealed a similar ability to differentiate between patients with balance problems in course of vestibular pathology and healthy participants, despite the differences observed between measuring methods. In some tests surface parameter may be more appropriate than sway velocity in improving MediPost sensitivity.

Evaluation of Functionality of Warning System in Smart Protective Clothing for Firefighters.

Recent achievements in the field of miniaturization of electronics have led to a significant interest in its application into the protective clothing for firefighters in order to improve their safety and health. However, up to now there are not any requirements and standardized test methods enabling confirmation of safety of use and functionality of these systems in work environment. In the paper, an importance of evaluation of such smart wearable system in predicted utility conditions is highlighted. Three variants of the specially developed personal warning systems (PWSs) for integration with either health status or environmental sensors to be used in smart protective clothing for firefighters are presented, i.e., with LCD display, LED diodes and vibrating element. For the purpose of evaluation a new testing methodology was developed. The PWSs were evaluated on a basis of perception of warning signals by firefighters in simulated utility conditions including temperature, light, noise, fog and performed activities. In the case of marching, even 75% of signals generated by PWS with LCD display were not received. Physical activity did not influence on functionality of PWS with vibrating element. For the PWS with LED diodes, the signal was received statistically significantly quicker than in the case of other PWS and the mean value of voice response time was below 3 s.

Fully Automatic Fall Risk Assessment Based on a Fast Mobility Test.

This paper presents a fall risk assessment approach based on a fast mobility test, automatically evaluated using a low-cost, scalable system for the recording and analysis of body movement. This mobility test has never before been investigated as a sole source of data for fall risk assessment. It can be performed in a very limited space and needs only minimal additional equipment, yet provides large amounts of information, as the presented system can obtain much more data than traditional observation by capturing minute details regarding body movement. The readings are provided wirelessly by one to seven low-cost micro-electro-mechanical inertial measurement units attached to the subject's body segments. Combined with a body model, these allow segment rotations and translations to be computed and for body movements to be recreated in software. The subject can then be automatically classified by an artificial neural network based on selected values in the test, and those with an elevated risk of falls can be identified. Results obtained from a group of 40 subjects of various ages, both healthy volunteers and patients with vestibular system impairment, are presented to demonstrate the combined capabilities of the test and system. Labelling of subjects as fallers and non-fallers was performed using an objective and precise sensory organization test; it is an important novelty as this approach to subject labelling has never before been used in the design and evaluation of fall risk assessment systems. The findings show a true-positive ratio of 85% and true-negative ratio of 63% for classifying subjects as fallers or non-fallers using the introduced fast mobility test, which are noticeably better than those obtained for the long-established Timed Up and Go test.

Evaluation of the impact of atmospheric pressure in different seasons on blood pressure in patients with arterial hypertension.

OBJECTIVES: Atmospheric pressure is the most objective weather factor because regardless of if outdoors or indoors it affects all objects in the same way. The majority of previous studies have used the average daily values of atmospheric pressure in a bioclimatic analysis and have found no correlation with blood pressure changes. The main objective of our research was to assess the relationship between atmospheric pressure recorded with a frequency of 1 measurement per minute and the results of 24-h blood pressure monitoring in patients with treated hypertension in different seasons in the moderate climate of the City of Lódz (Poland). MATERIAL AND METHODS: The study group consisted of 1662 patients, divided into 2 equal groups (due to a lower and higher average value of atmospheric pressure). Comparisons between blood pressure values in the 2 groups were performed using the Mann-Whitney U test. RESULTS: We observed a significant difference in blood pressure recorded during the lower and higher range of atmospheric pressure: on the days of the spring months systolic (p = 0.043) and diastolic (p = 0.005) blood pressure, and at nights of the winter months systolic blood pressure (p = 0.013). CONCLUSIONS: A significant inverse relationship between atmospheric pressure and blood pressure during the spring days and, only for systolic blood pressure, during winter nights was observed. Int J Occup Med Environ Health 2016;29(5):783-792.

Real-time prediction of acute cardiovascular events using hardware-implemented Bayesian networks.

This paper presents a decision support system that aims to estimate a patient׳s general condition and detect situations which pose an immediate danger to the patient׳s health or life. The use of this system might be especially important in places such as accident and emergency departments or admission wards, where a small medical team has to take care of many patients in various general conditions. Particular stress is laid on cardiovascular and pulmonary conditions, including those leading to sudden cardiac arrest. The proposed system is a stand-alone microprocessor-based device that works in conjunction with a standard vital signs monitor, which provides input signals such as temperature, blood pressure, pulseoxymetry, ECG, and ICG. The signals are preprocessed and analysed by a set of artificial intelligence algorithms, the core of which is based on Bayesian networks. The paper focuses on the construction and evaluation of the Bayesian network, both its structure and numerical specification.

Correlation between the activity of the autonomic nervous system and endothelial function in patients with acute coronary syndrome.

INTRODUCTION: The endothelium and sympathetic nervous system play an important role in the pathogenesis of acute coronary syndrome (ACS). OBJECTIVES: The aim of our study was to evaluate correlations between noninvasive markers of the endothelial function and the sympathetic nervous system in patients with a recent ACS. PATIENTS AND METHODS: The study included 52 patients who experienced an ACS within the previous 3 to 6 months. Endothelial function was expressed as the reactive hyperemia index (RHI), and the activity of the sympathetic nervous system--as latency and amplitude of sympathetic skin response (SSR) potentials from the 4 limbs. Linear and partial correlations between the RHI and SSR were calculated. RESULTS: There were significant correlations between the RHI and the latency of the SSR in the upper limbs (r = 0.34, P = 0.02 for the right limb; and r = 0.34, P = 0.01 for the left limb). After eliminating the effects of age, sex, weight, and glomerular filtration rate, the partial correlation between the RHI and the latency of the SSR in the upper limbs remained statistically significant (r = 0.41, P = 0.004 for the right limb, and r = 0.42, P = 0.004 for the left limb). There was no correlation between the RHI and latency of the SSR during the stimulation of the lower limbs. CONCLUSIONS: Our study confirmed the correlations between the sympathetic autonomic nervous system and endothelium in patients with ACS. The correlation of the RHI with the latency of the SSR was observed only in the upper limbs.