Quantification of Axial Abnormality Due to Cerebellar Ataxia with Inertial Measurements

Abstract

Cerebellar Ataxia (CA) leads to deficiencies in muscle movement and lack of coordination that is often manifested as gait and balance disabilities. Conventional CA clinical assessments are subjective, cumbersome and provide less insight into the functional capabilities of patients. This cross-sectional study investigates the use of wearable inertial sensors strategically positioned on the front-chest and upper-back locations during the Romberg and Trunk tests for objective assessment of human postural balance due to CA. The primary aim of this paper is to quantify the performance of postural stability of 34 patients diagnosed with CA and 22 healthy subjects as controls. Several forms of entropy descriptions were considered to uncover characteristics of movements intrinsic to CA. Indeed, correlation with clinical observation is vital in ascertaining the validity of the inertial measurements in addition to capturing unique features of movements not typically observed by the practicing clinician. Both of these aspects form an integral part of the underlying objective assessment scheme. Uncertainty in the velocity contained a significant level of information with respect to truncal instability and, based on an extensive clustering and discrimination analysis, fuzzy entropy was identified as an effective measure in characterising the underlying disability. Front-chest measurements demonstrated a strong correlation with clinical assessments while the upper-back measurements performed better in classifying the two cohorts, inferring that the standard clinical assessments are relatively influenced by the frontal observations. The Romberg test was confirmed to be an effective test of neurological diagnosis as well as a potential candidate for objective assessment resulting in a significant correlation with the clinical assessments. In contrast, the Trunk test is observed to be relatively less informative.

Objective Assessment of Cerebellar Ataxia: A Comprehensive and Refined Approach

“…Our overall aim is to construct superior tests for cerebellar disease for use by non-subspecialist clinicians; for deep phenotyping and identifying of biomarkers for possible CA treatment trials. In earlier studies [4][5][6][7][8][9][10][11] , we demonstrated that our instrumented devices were able to accurately emulate each of the individual bedside tests of cerebellar function and to go beyond this by grading impairment severity. The research outlined in this paper aimed to produce a composite score of CA (based on a reduced number of our instrumented tests).…”

“…The objective assessments of the nine neurological tests are grouped into the following 5 domains with a brief description of their execution protocol. A summary of features that proved pivotal in the diagnosis of CA in the related respective study 4,[6][7][8][9][10][11] has also been included for each test subsection in Table 2.…”

“…While wearable sensors are increasingly being explored as measurement tools for disability in neurological diseases like Parkinson's disease 12,13 and MS 14 , studies are still lacking in CA 15,16 with the potential of delivering a comprehensive, quantifiable, objective and meaningful measure of neurological function covering the 5 domains-speech, upper limb, lower limb, balance and gait. Our earlier studies [4][5][6][7][8][9][10][11] examined data from wearable sensors while subjects with CA and normal subjects (controls) performed one or more of the standard bedside tests for CA, pertaining to any one of the 5 domains. Our aim was to use the features extracted from this data to build statistical models that could accurately predict the presence and severity of CA as measured by the SARA and other similar scales.…”

“…In the present study we used the results obtained in the previous CA assessments in speech 4,6 , upper limb [7][8][9] , lower limb 7,8 , balance 10 and gait 11 domains. The aim was to investigate differences between controls and CA subjects.…”

Monitoring Movements of Ataxia Patient by Using UWB Technology

“…Currently, clinically it is difficult to find out the particular problem of the Ataxia patients and also more challenging work to monitoring the movements. The gesture imbalance in Ataxia people used the wearable detector to estimate their position [4]. With the help of UWB technology, detection of human walking activity and human body tracking are possible for actual implementation.…”