Epilepsy syndrome-associated balance dysfunction assessed by static posturography

AbstractPurposeTo compare subclinical balance dysfunction in patients with various epilepsy syndromes with apparently healthy subjects.MethodsTwenty-seven patients with localization-related epilepsy (LRE), 19 with primary generalized epilepsy (PGE), who had no subjective complaints of impaired balance and no abnormal neurologic findings on examination, and 22 apparently healthy subjects, underwent static posturography using the Posture Scale Analyzer (PSA) system.ResultsSway index was higher in patients compared to healthy subjects in all tests, significant for single leg stance (p=0.005). Patients with PGE had a higher sway index compared to patients with LRE in six of the tests, also significant for single leg stance (p=0.027). This difference was not affected by the type of AED treatment or disease duration.ConclusionPosturography can improve balance function assessment in patients with epilepsy, demonstrate subclinical impairment in seemingly asymptomatic patients, and further characterize balance deficits in different epilepsy syndromes

Development of an Automatic Perturbator for Dynamic Posturographic Analysis

The subject of this paper is a novel pneumo-tronic system aimed at applying impulsive force perturbations to the human body in order to elicit postural reactions. The development of the prototype is based on the use of a specifically realized experimental test bench. An analytical model of the whole system, including its interaction with both the subject\u2019s body and with the operator, is briefly presented. The test bench is used to validate the model and to perform experimental trials. The results confirm the validity of the model but call for a more accurate selection of the system components and of the control logic, in order to achieve the desired performance for such a demanding application

Changes in balance function with chronic antiepileptic drug therapy: A twin and sibling study

Objective: To investigate cross-sectional and longitudinal differences in static and dynamic standing balance measures and lower limb muscle strength in patients who are treated chronically with antiepileptic drugs (AEDs). Methods: Twenty-six AED exposure-discordant same-gender twin and sibling pairs were studied. Clinical and laboratory balance examinations were conducted twice, separated by at least 1 year. The mean within-pair differences in balance measures were calculated cross-sectionally at baseline and follow-up, and longitudinally. Results: No significant mean within-pair difference was found at baseline in age (44 years), weight, and height (p > 0.05). Between study assessments, the median (interquartile range [IQR]) interval was 3.0 (2.1-4.3) years in users and 2.9 (2.0-4.4) years in nonusers. The median duration of AED therapy was 19 (11-21) years. At baseline and follow-up, cross-sectional sway measures from posturography (Chattecx Balance System) and clinical static balance tests showed poorer performance in users compared to nonusers on several test conditions (p = 0.002-0.032). At follow-up, the users took longer than nonusers to complete the Four-Square-Step Test (p = 0.005) and Five-Times-Sit-to-Stand Test (p = 0.018). A greater annual rate of deterioration in sway was found in users compared to nonusers using posturography on the anteroposterior tilting platform task with distraction (p = 0.032). In both groups, higher baseline sway predicted greater annual deterioration in sway in all platform conditions (ß = 0.3-0.5, p < 0.001-0.013). The annual change in measures did not differ between groups in the clinical balance and lower limb strength assessments. Significance: In this longitudinal twin and sibling study, chronic AED users had poorer standing balance compared to nonusers. Users showed greater deterioration in postural sway with one dynamic platform condition. AEDs may progressively impair balance mechanisms, although this requires further investigations. Repeated dynamic posturography could provide a basis for preventive trials for maintaining or improving balance

Pneumo-tronic Perturbator for the Study of Human Postural Responses

Abstract Author keywords Indexed keywords SciVal Topics Metrics Abstract This paper describes the design and operational principles of a device that imparts a well-controlled mechanical force or impulse, a so-called perturbation, to a pre-selected point on the surface of the human body. This perturbator will be integrated within a system aimed at measuring and evaluating human postural reaction in a clinically meaningful way. The ease of use and versatility of the device renders it suitable for manual operation but it can also be integrated in a robotized system. The hardware, control law and characterization of the perturbator are presented. Preliminary results indicate that the device is able to generate repeatable perturbations with characteristics appropriate to the intended application. Further improvements are discussed and proposed