Periodic Reporting for period 1 - CP-RehOP (Responding or not responding to training; prediction of balance rehabilitation outcome from structural and functional brain networks in Cerebral Palsy.)
Reporting period: 2016-03-01 to 2018-02-28
Since the success of well-targeted treatment depends on this basic knowledge, a novel experiment was performed that provides fundamental insights in both areas. The current project, therefore, entailed a virtual reality training paradigm to train balance in children with CP. Balance is tested comprehensively in these children, before and after training, using both clinical scales as biomechanical measures. Additionally, brain imaging scans have been performed before and after training.
Therefore, the objectives of the current project were;
1. Determine the best practice diagnostic tool for balance control in Cerebral Palsy.
2. Define the functional and structural brain networks involved in balance control in Cerebral Palsy.
3. Identify the underlying neural causes of responsiveness, and the prediction of individual responsiveness based on medical brain images.
The first aim of the CP-RehOP project was to determine the best diagnostic tool for imbalance in CP. Therefore, we have assessed both clinical and biomechanical measures in children with CP – data collection ongoing. Often used clinical scales were assessed including the Pediatric Balance Scale, ‘balance’ and ‘running speed and agility’ subtest of Bruininks-Oseretsky Test of Motor Proficiency, and 3) Trunk Control Measurement Scale. Additionally, biomechanical measures have been assessed while walking on the GRAIL-system (Motek, Amsterdam), which consists of an instrumented dual-belt treadmill, with motion-capture and synchronized VR. From these measurements, biomechanical measures of balance during perturbed and unperturbed walking were extracted, including spatiotemporal gait parameters of the legs (e.g. step width, step time variability) and kinematics of the arms (as these are related to gait instability in CP), Margins of Stability, Gait Sensitivity Norm, and Foot Placement Estimator. Additionally, on the GRAIL the Sensory Organization Test was evaluated to assess the individual’s ability to use visual, proprioceptive and vestibular cues to maintain postural stability in stance, using posturography. As such, this project can for the first time assess the relationship between clinical tests and experimental balance measures in CP, thus, provide an answer to how to diagnose balance control in this population.
To investigate the second and third aim, diffusion tensor imaging and resting state functional magnetic resonance imaging scans were acquired in the same group of children with CP – data collection ongoing. Given the wide range of affected brain areas in CP, a whole-brain and graph-theoretical approach is used to determine specific neural biomarkers of impaired balance control. From the neural biomarkers identified in these neuroimaging scans, underlying neural causes of non-responsiveness to balance training can be identified for the first time in CP. These results provide important new insights into the possible reason of the inconsistent results concerning the efficacy of balance training paradigms in CP. Additionally, the combination of behavioral and neurological assessments allows for the prediction of individual responsiveness of a patient based on medical brain images.
Finally, literature suggests that improvements after VR training observed in CP are associated to changes in the reorganization of neural networks. However, this has not been investigated for balance in CP. To the best of our knowledge, in CP only two pilot studies have investigated functional neuroplastic changes after training. These two pilots investigated the adaptations in cortical activation after treadmill training, using magnetoencephalography and fMRI, in only in 4 and 3 children with CP, respectively. In CP-RehOP, diffusion tensor imaging and resting state functional magnetic resonance imaging scans are acquired in the same group of children with CP before and after VR training. These scans allow for the first time the assessment of training-induced brain structural and functional neuroplasticity.