Roberto Llorens

Effectiveness of a Wii balance board-based system (eBaViR) for balance rehabilitation: a pilot randomized clinical trial in patients with acquired brain injury

BackgroundAcquired brain injury (ABI) is the main cause of death and disability among young adults. In most cases, survivors can experience balance instability, resulting in functional impairments that are associated with diminished health-related quality of life. Traditional rehabilitation therapy may be tedious. This can reduce motivation and adherence to the treatment and thus provide a limited benefit to patients with balance disorders. We present eBaViR (easy Balance Virtual Rehabilitation), a system based on the Nintendo® Wii Balance Board® (WBB), which has been designed by clinical therapists to improve standing balance in patients with ABI through motivational and adaptative exercises. We hypothesize that eBaViR, is feasible, safe and potentially effective in enhancing standing balance.MethodsIn this contribution, we present a randomized and controlled single blinded study to assess the influence of a WBB-based virtual rehabilitation system on balance rehabilitation with ABI hemiparetic patients. This study describes the eBaViR system and evaluates its effectiveness considering 20 one-hour-sessions of virtual reality rehabilitation (n = 9) versus standard rehabilitation (n = 8). Effectiveness was evaluated by means of traditional static and dynamic balance scales.ResultsThe final sample consisted of 11 men and 6 women. Mean ± SD age was 47.3 ± 17.8 and mean ± SD chronicity was 570.9 ± 313.2 days. Patients using eBaViR had a significant improvement in static balance (p = 0.011 in Berg Balance Scale and p = 0.011 in Anterior Reaches Test) compared to patients who underwent traditional therapy. Regarding dynamic balance, the results showed significant improvement over time in all these measures, but no significant group effect or group-by-time interaction was detected for any of them, which suggests that both groups improved in the same way. There were no serious adverse events during treatment in either group.ConclusionsThe results suggest that eBaViR represents a safe and effective alternative to traditional treatment to improve static balance in the ABI population. These results have encouraged us to reinforce the virtual treatment with new exercises, so an evolution of the system is currently being developed.

Effectiveness, usability, and cost-benefit of a virtual reality-based telerehabilitation program for balance recovery after stroke: a randomized controlled trial

OBJECTIVES First, to evaluate the clinical effectiveness of a virtual reality (VR)-based telerehabilitation program in the balance recovery of individuals with hemiparesis after stroke in comparison with an in-clinic program; second, to compare the subjective experiences; and third, to contrast the costs of both programs. DESIGN Single-blind, randomized, controlled trial. SETTING Neurorehabilitation unit. PARTICIPANTS Chronic outpatients with stroke (N=30) with residual hemiparesis. INTERVENTIONS Twenty 45-minute training sessions with the telerehabilitation system, conducted 3 times a week, in the clinic or in the home. MAIN OUTCOME MEASURES First, Berg Balance Scale for balance assessment. The Performance-Oriented Mobility Assessment balance and gait subscales, and the Brunel Balance Assessment were secondary outcome measures. Clinical assessments were conducted at baseline, 8 weeks (posttreatment), and 12 weeks (follow-up). Second, the System Usability Scale and the Intrinsic Motivation Inventory for subjective experiences. Third, cost (in dollars). RESULTS Significant improvement in both groups (in-clinic group [control] and a home-based telerehabilitation group) from the initial to the final assessment in the Berg Balance Scale (ηp(2)=.68; P=.001), in the balance (ηp(2)=.24; P=.006) and gait (ηp(2)=.57, P=.001) subscales of the Tinetti Performance-Oriented Mobility Assessment, and in the Brunel Balance Assessment (control: χ(2)=15.0; P=.002; experimental: χ(2)=21.9; P=.001). No significant differences were found between the groups in any balance scale or in the feedback questionnaires. With regard to subjective experiences, both groups considered the VR system similarly usable and motivating. The in-clinic intervention resulted in more expenses than did the telerehabilitation intervention (

Improvement in balance using a virtual reality-based stepping exercise: a randomized controlled trial involving individuals with chronic stroke:

654.72 per person). CONCLUSIONS First, VR-based telerehabilitation interventions can promote the reacquisition of locomotor skills associated with balance in the same way as do in-clinic interventions, both complemented with a conventional therapy program; second, the usability of and motivation to use the 2 interventions can be similar; and third, telerehabilitation interventions can involve savings that vary depending on each scenario.

Metal artifact reduction in dental CT images using polar mathematical morphology

Objective: To study the clinical effectiveness and the usability of a virtual reality-based intervention compared with conventional physical therapy in the balance recovery of individuals with chronic stroke. Design: Randomized controlled trial. Setting: Outpatient neurorehabilitation unit. Participants: A total of 20 individuals with chronic stroke. Interventions: The intervention consisted of 20 one-hour sessions, five sessions per week. The experimental group combined 30 minutes with the virtual reality-based intervention with 30 minutes of conventional training. The control group underwent one hour conventional therapy. Main measures: Balance performance was assessed at the beginning and at the end of the trial using the Berg Balance Scale, the balance and gait subscales of the Tinetti Performance-Oriented Mobility Assessment, the Brunel Balance Assessment, and the 10-m Walking Test. Subjective data of the virtual reality-based intervention were collected from the experimental group, with a feedback questionnaire at the end of the trial. Results: The results revealed a significant group-by-time interaction in the scores of the Berg Balance Scale (p < 0.05) and in the 10-m Walking Test (p < 0.05). Post-hoc analyses showed greater improvement in the experimental group: 3.8 ±2.6 vs. 1.8 ±1.4 in the Berg Balance Scale, –1.9 ±1.6 seconds vs. 0.0 ±2.3 seconds in the 10-m Walking Test, and also in the number of participants who increased level in the Brunel Balance Assessment (χ2 = 2.5, p < 0.01). Conclusions: Virtual reality interventions can be an effective resource to enhance the improvement of balance in individuals with chronic stroke.

Effect of a mixed reality-based intervention on arm, hand, and finger function on chronic stroke

Most dental implant planning systems use a 3D representation of the CT scan of the patient under study as it provides a more intuitive view of the human jaw. The presence of metallic objects in human jaws, such as amalgam or gold fillings, provokes several artifacts like streaking and beam hardening which makes the reconstruction process difficult. In order to reduce these artifacts, several methods have been proposed using the raw data, directly obtained from the tomographs, in different ways. However, in DICOM-based applications this information is not available, and thus the need of a new method that handles this task in the DICOM domain. The presented method performs a morphological filtering in the polar domain yielding output images less affected by artifacts (even in cases of multiple metallic objects) without causing significant smoothing of the anatomic structures, which allows a great improvement in the 3D reconstruction. The algorithm has been automated and compared to other image denoising methods with successful results.

Validation of a low-cost virtual reality system for training street-crossing. A comparative study in healthy, neglected and non-neglected stroke individuals

BackgroundVirtual and mixed reality systems have been suggested to promote motor recovery after stroke. Basing on the existing evidence on motor learning, we have developed a portable and low-cost mixed reality tabletop system that transforms a conventional table in a virtual environment for upper limb rehabilitation. The system allows intensive and customized training of a wide range of arm, hand, and finger movements and enables interaction with tangible objects, while providing audiovisual feedback of the participants’ performance in gamified tasks. This study evaluates the clinical effectiveness and the acceptance of an experimental intervention with the system in chronic stroke survivors.MethodsThirty individuals with stroke were included in a reversal (A-B-A) study. Phase A consisted of 30 sessions of conventional physical therapy. Phase B consisted of 30 training sessions with the experimental system. Both interventions involved flexion and extension of the elbow, wrist, and fingers, and grasping of different objects. Sessions were 45-min long and were administered three to five days a week. The body structures (Modified Ashworth Scale), functions (Motricity Index, Fugl-Meyer Assessment Scale), activities (Manual Function Test, Wolf Motor Function Test, Box and Blocks Test, Nine Hole Peg Test), and participation (Motor Activity Log) were assessed before and after each phase. Acceptance of the system was also assessed after phase B (System Usability Scale, Intrinsic Motivation Inventory).ResultsSignificant improvement was detected after the intervention with the system in the activity, both in arm function measured by the Wolf Motor Function Test (p < 0.01) and finger dexterity measured by the Box and Blocks Test (p < 0.01) and the Nine Hole Peg Test (p < 0.01); and participation (p < 0.01), which was maintained to the end of the study. The experimental system was reported as highly usable, enjoyable, and motivating.ConclusionsOur results support the clinical effectiveness of mixed reality interventions that satisfy the motor learning principles for upper limb rehabilitation in chronic stroke survivors. This characteristic, together with the low cost of the system, its portability, and its acceptance could promote the integration of these systems in the clinical practice as an alternative to more expensive systems, such as robotic instruments.

The Role of Virtual Motor Rehabilitation: A Quantitative Analysis Between Acute and Chronic Patients With Acquired Brain Injury

Unilateral spatial neglect is a common consequence of stroke that directly affects the performance of activities of daily living. This impairment is traditionally assessed with paper-and-pencil tests that can lack correspondence to real life and are easily compensated. Virtual reality can immerse patients in more ecological scenarios, thus providing therapists with new tools to assess and train the effects of this impairment in simulated real tasks. This paper presents the clinical validation and convergent validity of a low-cost virtual reality system for training street-crossing in stroke patients with and without neglect. The performance of neglect patients was significantly worse than the performance of non-neglect and healthy participants. In addition, several correlations between the scores in the system and in the traditional scales were detected.

Jaw tissues segmentation in dental 3D CT images using fuzzy-connectedness and morphological processing

Acquired brain injury (ABI) is one of the main problems of disability and death in the world. Its incidence and survival rate are increasing annually. Thus, the number of chronic ABI patients is gradually growing. Traditionally, rehabilitation programs are applied to postacute and acute patients, but recent publications determine that chronic patients may benefit from rehabilitation. Also, in the last few years, the potential of virtual rehabilitation (VR) systems has been demonstrated. However, until now, no previous studies have been carried out to compare the evolution of chronic patients with acute patients in a VR program. To perform this study, we developed a VR system for ABI patients. The system, vestibular virtual rehabilitation (V2R), was designed with clinical specialists. V2R has been tested with 21 people ranging in age from 18 to 80 years old that were classified in two groups: chronic patients and acute patients. The results demonstrate a similar recovery for chronic and acute patients during the intervention period. Also, the results showed that chronic patients stop their improvement when they finish their training. This conclusion encourages us to direct our developments toward VR systems that can be easily integrated at home, allowing chronic patients to have a permanent VR training program.

Posturography using the Wii Balance Board™: A feasibility study with healthy adults and adults post-stroke.

The success of oral surgery is subject to accurate advanced planning. In order to properly plan for dental surgery or a suitable implant placement, it is necessary an accurate segmentation of the jaw tissues: the teeth, the cortical bone, the trabecular core and over all, the inferior alveolar nerve. This manuscript presents a new automatic method that is based on fuzzy connectedness object extraction and mathematical morphology processing. The method uses computed tomography data to extract different views of the jaw: a pseudo-orthopantomographic view to estimate the path of the nerve and cross-sectional views to segment the jaw tissues. The method has been tested in a groundtruth set consisting of more than 9000 cross-sections from 20 different patients and has been evaluated using four similarity indicators (the Jaccard index, Dices coefficient, point-to-point and point-to-curve distances), achieving promising results in all of them (0.726±0.031, 0.840±0.019, 0.144±0.023 mm and 0.163±0.025 mm, respectively). The method has proven to be significantly automated and accurate, with errors around 5% (of the diameter of the nerve), and is easily integrable in current dental planning systems.

BioTrak: análisis de efectividad y satisfacción de un sistema de realidad virtual para la rehabilitación del equilibrio en pacientes con daño cerebral

BACKGROUND Posturography systems that incorporate force platforms are considered to assess balance and postural control with greater sensitivity and objectivity than conventional clinical tests. The Wii Balance Board (WBB) system has been shown to have similar performance characteristics as other force platforms, but with lower cost and size. OBJECTIVES To determine the validity and reliability of a freely available WBB-based posturography system that combined the WBB with several traditional balance assessments, and to assess the performance of a cohort of stroke individuals with respect to healthy individuals. METHODS Healthy subjects and individuals with stroke were recruited. Both groups were assessed using the WBB-based posturography system. Individuals with stroke were also assessed using a laboratory grade posturography system and a battery of clinical tests to determine the concurrent validity of the system. A group of subjects were assessed twice with the WBB-based system to determine its reliability. RESULTS A total of 144 healthy individuals and 53 individuals with stroke participated in the study. Concurrent validity with another posturography system was moderate to high. Correlations with clinical scales were consistent with previous research. The reliability of the system was excellent in almost all measures. In addition, the system successfully characterized individuals with stroke with respect to the healthy population. CONCLUSIONS The WBB-based posturography system exhibited excellent psychometric properties and sensitivity for identifying balance performance of individuals with stroke in comparison with healthy subjects, which supports feasibility of the system as a clinical tool.