Citations
To investigate the effects of using motor imagery (MI) in combination with a virtual reality (VR) program on healthy volunteers and stroke patients. In addition, this study investigated whether task variability within the VR-guided MI programs would influence corticomotor excitability.
The present study included 15 stroke patients and 15 healthy right-handed volunteers who were presented with four different conditions in a random order: rest, MI alone, VR-guided MI, and VR-guided MI with task variability. The corticomotor excitability of each participant was assessed before, during, and after each condition by measuring changes in the various parameters of motor-evoked potentials (MEPs) of the extensor carpi radials (ECR). Changes in intracortical inhibition (ICI) and intracortical facilitation (ICF) were calculated after each condition as percentages of inhibition (%INH) and facilitation (%FAC) at rest.
In both groups, the increases in MEP amplitudes were greater during the two VR-guided MI conditions than during MI alone. Additionally, the reductions in ECR %INH in both groups were greater under the condition involving VR-guided MI with task variability than under that involving VR-guided MI with regular interval.
The corticomotor excitability elicited by MI using a VR avatar representation was greater than that elicited by MI with real body observations. Furthermore, the use of task variability in a VR program may enhance neural regeneration after stroke by reducing ICI. The present findings support the use of various VR programs as well as the concept of combining MI with VR programs for neurorehabilitation.
Citations
To improve lower extremity function and balance in elderly persons, we developed a novel, three-dimensional interactive augmented reality system (3D ARS). In this feasibility study, we assessed clinical and kinematic improvements, user participation, and the side effects of our system.
Eighteen participants (age, 56-76 years) capable of walking independently and standing on one leg were recruited. The participants received 3D ARS training during 10 sessions (30-minute duration each) for 4 weeks. Berg Balance Scale (BBS) and the Timed Up and Go (TUG) scores were obtained before and after the exercises. Outcome performance variables, including response time and success rate, and kinematic variables, such as hip and knee joint angle, were evaluated after each session.
Participants exhibited significant clinical improvements in lower extremity balance and mobility following the intervention, as shown by improved BBS and TUG scores (p<0.001). Consistent kinematic improvements in the maximum joint angles of the hip and knee were observed across sessions. Outcome performance variables, such as success rate and response time, improved gradually across sessions, for each exercise. The level of participant interest also increased across sessions (p<0.001). All participants completed the program without experiencing any adverse effects.
Substantial clinical and kinematic improvements were observed after applying a novel 3D ARS training program, suggesting that this system can enhance lower extremity function and facilitate assessments of lower extremity kinematic capacity.
Citations
To investigate whether virtual reality (VR) training will help the recovery of cognitive function in brain tumor patients.
Thirty-eight brain tumor patients (19 men and 19 women) with cognitive impairment recruited for this study were assigned to either VR group (n=19, IREX system) or control group (n=19). Both VR training (30 minutes a day for 3 times a week) and computer-based cognitive rehabilitation program (30 minutes a day for 2 times) for 4 weeks were given to the VR group. The control group was given only the computer-based cognitive rehabilitation program (30 minutes a day for 5 days a week) for 4 weeks. Computerized neuropsychological tests (CNTs), Korean version of Mini-Mental Status Examination (K-MMSE), and Korean version of Modified Barthel Index (K-MBI) were used to evaluate cognitive function and functional status.
The VR group showed improvements in the K-MMSE, visual and auditory continuous performance tests (CPTs), forward and backward digit span tests (DSTs), forward and backward visual span test (VSTs), visual and verbal learning tests, Trail Making Test type A (TMT-A), and K-MBI. The VR group showed significantly (p<0.05) better improvements than the control group in visual and auditory CPTs, backward DST and VST, and TMT-A after treatment.
VR training can have beneficial effects on cognitive improvement when it is combined with computer-assisted cognitive rehabilitation. Further randomized controlled studies with large samples according to brain tumor type and location are needed to investigate how VR training improves cognitive impairment.
Citations
To investigate the effectiveness of commercial gaming-based virtual reality (VR) therapy on the recovery of paretic upper extremity in subacute stroke patients.
Twenty patients with the first-onset subacute stroke were enrolled and randomly assigned to the case group (n=10) and the control group (n=10). Primary outcome was measured by the upper limb score through the Fugl-Meyer Assessment (FMA-UL) for the motor function of both upper extremities. Secondary outcomes were assessed for motor function of both upper extremities including manual function test (MFT), box and block test (BBT), grip strength, evaluated for activities of daily living (Korean version of Modified Barthel Index [K-MBI]), and cognitive functions (Korean version of the Mini-Mental State Examination [K-MMSE] and continuous performance test [CPT]). The case group received commercial gaming-based VR therapy using Wii (Nintendo, Tokyo, Japan), and the control group received conventional occupational therapy (OT) for 30 minutes a day during the period of 4 weeks. All patients were evaluated before and after the 4-week intervention.
There were no significant differences in the baseline between the two groups. After 4 weeks, both groups showed significant improvement in the FMA-UL, MFT, BBT, K-MBI, K-MMSE, and correct detection of auditory CPT. However, grip strength was improved significantly only in the case group. There were no significant intergroup differences before and after the treatment.
These findings suggested that the commercial gaming-based VR therapy was as effective as conventional OT on the recovery of upper extremity motor and daily living function in subacute stroke patients.
Citations
To investigate the effect of virtual reality (VR) and a tetra-ataxiometric posturography (Tetrax) program on stroke patients with impaired standing balance.
Thirty acute stroke patients with impaired standing balance were recruited and randomly assigned to a VR, Tetrax, or control group. All patients received conventional balance training as a baseline; and VR and Tetrax patients received VR or Tetrax treatment, in addition. The primary outcome measures to evaluate the overall standing balance were the Berg Balance Scale (BBS) and the falling index (FI). The secondary outcome measures were the stability index (SI) and the weight distribution index (WDI), which were used to evaluate the balance status according to specific body positions. The FI, SI, and WDI were measured using the Tetrax instrument.
The BBS and FI scores were improved in all groups, with no significant differences between groups. In open-eyed positions, the VR group showed significantly greater improvement in SI and WDI scores than the control group (p<0.017). In closed-eyed positions, the Tetrax group showed significantly greater improvement in SI and WDI scores than the control group (p<0.017).
The inclusion of VR and Tetrax programs did not lead to an overall benefit in balance. VR and Tetrax did, however, demonstrate a benefit in specific positions. A Tetrax program may benefit patients with abnormal proprioceptive function, whereas a VR program may benefit patients with normal sensory function.
Citations
To investigate the effect of virtual reality on the recovery of cognitive impairment in stroke patients.
Twenty-eight patients (11 males and 17 females, mean age 64.2) with cognitive impairment following stroke were recruited for this study. All patients were randomly assigned to one of two groups, the virtual reality (VR) group (n=15) or the control group (n=13). The VR group received both virtual reality training and computer-based cognitive rehabilitation, whereas the control group received only computer-based cognitive rehabilitation. To measure, activity of daily living cognitive and motor functions, the following assessment tools were used: computerized neuropsychological test and the Tower of London (TOL) test for cognitive function assessment, Korean-Modified Barthel index (K-MBI) for functional status evaluation, and the motricity index (MI) for motor function assessment. All recruited patients underwent these evaluations before rehabilitation and four weeks after rehabilitation.
The VR group showed significant improvement in the K-MMSE, visual and auditory continuous performance tests (CPT), forward digit span test (DST), forward and backward visual span tests (VST), visual and verbal learning tests, TOL, K-MBI, and MI scores, while the control group showed significant improvement in the K-MMSE, forward DST, visual and verbal learning tests, trail-making test-type A, TOL, K-MBI, and MI scores after rehabilitation. The changes in the visual CPT and backward VST in the VR group after rehabilitation were significantly higher than those in the control group.
Our findings suggest that virtual reality training combined with computer-based cognitive rehabilitation may be of additional benefit for treating cognitive impairment in stroke patients.
Citations
To investigate the effect of virtual reality training on unilateral spatial neglect in stroke patients.
Twenty-four stroke patients (14 males and 10 females, mean age=64.7) who had unilateral spatial neglect as a result of right hemisphere stroke were recruited. All patients were randomly assigned to either the virtual reality (VR) group (n=12) or the control group (n=12). The VR group received VR training, which stimulated the left side of their bodies. The control group received conventional neglect therapy such as visual scanning training. Both groups received therapy for 30 minutes a day, five days per week for three weeks. Outcome measurements included star cancellation test, line bisection test, Catherine Bergego scale (CBS), and the Korean version of modified Barthel index (K-MBI). These measurements were taken before and after treatment.
There were no significant differences in the baseline characteristics and initial values between the two groups. The changes in star cancellation test results and CBS in the VR group were significantly higher than those of the control group after treatment. The changes in line bisection test score and the K-MBI in the VR group were not statistically significant.
This study suggests that virtual reality training may be a beneficial therapeutic technique on unilateral spatial neglect in stroke patients.
Citations
Objective: To evaluate safely the driving ability of the handicapped with developed driving simulator in the virtual environment and to investigate clinical usefulness.
Method: A real car was remodeled for realism and equipped it with hand control device for driving of the handicapped. The subjects were 10 normal people with driving license and 15 patients with thoracic or lumbar spinal cord injury who had driving experience. 5 driving skills were measured (average speed, steering stability, centerline violation, traffic signal violation, and time taken in driving) in various road conditions. The normal participants manipulated the gas pedal and the brake by their foot while the patients did with their hands. After they finished to drive the whole course, they answered the questions ("How realistic the driving simulator seems to you" and "How much your fear reduced")
Results: 1) Four driving skills measured between two groups (normal vs. handicapped) were not significantly different (p>0.05). 2) In 4 kinds (start road, speed limit road, sharp curve road and left turn) of the road conditions, the average speed of the patients group was significantly different from the normal group (p<0.05). 3) Eleven patients (73%) reported that their driving fear was reduced and the score of "how realistic" question was 51.5% in average.
Conclusion: This developed driving simulator will be able to be used for one of the programs for evaluating and training the driving skill of the handicapped and need to enhance the reality of driving simulator. (J Korean Acad Rehab Med 2002; 26: 311-315)
Currently the evaluations of upper extremity motion have relied on a task-oriented approach to gain an accurate clinical picture of the functional capacities. As it is, an adequate and objective system to estimate upper extremity function is yet to be developed.
Authors used the virtual reality motion analysis system(VRMAS) which was developed by us for the purpose of investigating the kinematics of upper extremity motion during drinking a cup of water. Four healthy male adult subjects were recruited from the hospital personnels. After each subject sat down on a chair resting against the backrest in a neutral position, in front of a table he was instructed to drink the content of the cup from the table.
The data was analized and showed the following results. While drinking, the hand movements were smooth and linear. There were six distinct stages during drinking a cup of water; a reaching for the cup(stage 1), picking up the cup and carrying the cup to the mouth(stage 2), extending neck and drinking from the cup(stage 3), flexing neck(stage 4), replacing the cup to the table(stage 5), and returning to the start position(stage 6). During the stage 1 and 2, of all joint motions, the shoulder adduction and elbow flexion were most prominent. The stage 3 showed the most complex movements in shoulder flexion, forearm pronation, and wrist extension which were simultaneous. Remaining stages were the reversal of the first three stages. We could observe the ranges of motion of neck, shoulder, elbow, and wrist joint as well as the relationships of these joints at the same time.
In conclusion, VRMAS could be a very useful evaluation tool for the upper extremity motion and for obtaining the kinematic data from the upper extremity motion analysis.
Isotonic exercise occurs when the tension or torque generated by a muscle is constant throughout the movement. In practice it is very difficult to maintain the tension constant. Evaluation of isotonic exercise should include the works of concentric and eccentric contraction and the changes in tension and torque during joint motion. However, optimal evaluation tools for isotonic exercise has yet to be developed.
We authors, used virtual reality motion analysis system(VRMAS) which was codeveloped by us and EMG system(Cardwell Excel). Healthy male adult subjects(n=10) were recruited from hospital personnel. After dominant upper arm and trunk of each subject was fixed with velcro, he was instructed to repeat flexion and extension of his dominant elbow grasping dumbell (9 kg) in hand with maximal velocity as possible as can until the point of exhaustion. We measured the elbow angle, the angular velocity, torque, power, total work and the work of concentric and eccentric contraction during exercise.
The results were as follows: there were four distinct elbow flexor muscle contractions during flexion and extension of the elbow with the first and the second contractions during concentric contraction and the third and the fourth contractions during eccentric contraction. Between the peaks of contraction, motion was maintained due to the momentum that was generated. Of the ten subjects, seven had higher concentric work than eccentric work with the eccentric work being higher in the remaining three. But there was no statistic significance between the works of concentric contraction and eccentric contraction(p>0.05). The biggest work was observed in the fourth contraction, while the third contraction showed the least work(p<0.05).
In conclusion, there were four distinct muscle contractions during elbow isotonic exercise and the works of each muscle contraction were different. This result is contrary to the definition of isotonic exercise. This study also shows that the VRMAS could be a very useful evaluation tool for several types of isotonic exercise.