A Hand-Held Device Presenting Haptic Directional Cues for the Visually Impaired.

Haptic information is essential in everyday activities, especially for visually impaired people in terms of real-world navigation. Since human haptic sensory processing is nonlinear, asymmetric vibrations have been widely studied to create a pulling sensation for the delivery of directional haptic cues. However, the design of an input control signal that generates asymmetric vibrations has not yet been parameterised. In particular, it is unclear how to quantify the asymmetry of the output vibrations to create a better pulling sensation. To better understand the design of an input control signal that generates haptic directional cues, we evaluated the effect of the pulling sensations corresponding to the three adjustable parameters (i.e., delay time, ramp-down step length, and cut-off voltage) in a commonly applied step-ramp input signal. The results of a displacement measurement and a psychophysical experiment demonstrate that when the quantified asymmetry ratio is in a range of 0.3430-0.3508 with an optimised cut-off voltage for our hand-held device, the haptic directional cues are better perceived by participants. Additionally, the results also showed a superior performance in haptic delivery by shear forces than normal forces.

A pilot single-blind multicentre randomized controlled trial to evaluate the potential benefits of computer-assisted arm rehabilitation gaming technology on the arm function of children with spastic cerebral palsy.

OBJECTIVE: To evaluate the potential benefits of computer-assisted arm rehabilitation gaming technology on arm function of children with spastic cerebral palsy. DESIGN: A single-blind randomized controlled trial design. Power calculations indicated that 58 children would be required to demonstrate a clinically important difference. SETTING: Intervention was home-based; recruitment took place in regional spasticity clinics. PARTICIPANTS: A total of 15 children with cerebral palsy aged five to 12 years were recruited; eight to the device group. INTERVENTIONS: Both study groups received 'usual follow-up treatment' following spasticity treatment with botulinum toxin; the intervention group also received a rehabilitation gaming device. MAIN MEASURES: ABILHAND-kids and Canadian Occupational Performance Measure were performed by blinded assessors at baseline, six and 12 weeks. RESULTS: An analysis of covariance showed no group differences in mean ABILHAND-kids scores between time points. A non-parametric analysis of variance on Canadian Occupational Performance Measure scores showed a statistically significant improvement across time points (χ2 (2,15) = 6.778, p = 0.031), but this improvement did not reach minimal clinically important difference. Mean daily device use was seven minutes. Recruitment did not reach target owing to unanticipated staff shortages in clinical services. Feedback from children and their families indicated that the games were not sufficiently engaging to promote sufficient use that was likely to result in functional benefits. CONCLUSION: This study suggests that computer-assisted arm rehabilitation gaming does not benefit arm function, but a Type II error cannot be ruled out.

Home-based Computer Assisted Arm Rehabilitation (hCAAR) robotic device for upper limb exercise after stroke: results of a feasibility study in home setting.

BACKGROUND: Home-based robotic technologies may offer the possibility of self-directed upper limb exercise after stroke as a means of increasing the intensity of rehabilitation treatment. The current literature has a paucity of robotic devices that have been tested in a home environment. The aim of this research project was to evaluate a robotic device Home-based Computer Assisted Arm Rehabilitation (hCAAR) that can be used independently at home by stroke survivors with upper limb weakness. METHODS: hCAAR device comprises of a joystick handle moved by the weak upper limb to perform tasks on the computer screen. The device provides assistance to the movements depending on users ability. Nineteen participants (stroke survivors with upper limb weakness) were recruited. Outcome measures performed at baseline (A0), at end of 8-weeks of hCAAR use (A1) and 1 month after end of hCAAR use (A2) were: Optotrak kinematic variables, Fugl Meyer Upper Extremity motor subscale (FM-UE), Action Research Arm Test (ARAT), Medical Research Council (MRC) and Modified Ashworth Scale (MAS), Chedoke Arm and Hand Activity Inventory (CAHAI) and ABILHAND. RESULTS: Two participants were unable to use hCAAR: one due to severe paresis and the other due to personal problems. The remaining 17 participants were able to use the device independently in their home setting. No serious adverse events were reported. The median usage time was 433 minutes (IQR 250 - 791 min). A statistically significant improvement was observed in the kinematic and clinical outcomes at A1. The median gain in the scores at A1 were by: movement time 19%, path length 15% and jerk 19%, FM-UE 1 point, total MAS 1.5 point, total MRC 2 points, ARAT 3 points, CAHAI 5.5 points and ABILHAND 3 points. Three participants showed clinically significant improvement in all the clinical outcomes. CONCLUSIONS: The hCAAR feasibility study is the first clinical study of its kind reported in the current literature; in this study, 17 participants used the robotic device independently for eight weeks in their own homes with minimal supervision from healthcare professionals. Statistically significant improvements were observed in the kinematic and clinical outcomes in the study.

Investigating the International Classification of Functioning, Disability, and Health (ICF) Framework to Capture User Needs in the Concept Stage of Rehabilitation Technology Development.

This study evaluates whether the International Classification of Functioning, Disability, and Health (ICF) framework provides a useful basis to ensure that key user needs are identified in the development of a home-based arm rehabilitation system for stroke patients. Using a qualitative approach, nine people with residual arm weakness after stroke and six healthcare professionals with expertise in stroke rehabilitation were enrolled in the user-centered design process. They were asked, through semi-structured interviews, to define the needs and specification for a potential home-based rehabilitation device to facilitate self-managed arm exercise. The topic list for the interviews was derived by brainstorming ideas within the clinical and engineering multidisciplinary research team based on previous experience and existing literature in user-centered design. Meaningful concepts were extracted from questions and responses of these interviews. These concepts obtained were matched to the categories within the ICF comprehensive core set for stroke using ICF linking rules. Most of the concepts extracted from the interviews matched to the existing ICF Core Set categories. Person factors like gender, age, interest, compliance, motivation, choice, and convenience that might determine device usability are yet to be categorized within the ICF comprehensive core set. The results suggest that the categories of the comprehensive ICF Core Set for stroke provide a useful basis for structuring interviews to identify most users needs. However some personal factors (related to end users and healthcare professionals) need to be considered in addition to the ICF categories.

The Use of Kinematic Features in Evaluating Upper Limb Motor Function Learning Progress Based on Machine Learning.

Evaluating progress throughout a patient's rehabilitation process helps choose effective treatment and formulate personalised and evidence-based rehabilitation interventions. The evaluation process is difficult due to the limitations of current clinical assessments. They lack the ability to reflect sensitive changes continuously throughout the rehabilitation process. Kinematic features have been extracted from individual's movement to address this problem due to their sensitivity and continuity. However, choosing appropriate kinematic features for rehabilitation evaluation has always been challenging. This paper exploits the application of kinematic features to classify movement patterns and movement qualities. 12 kinematic features were firstly extracted from a 7-segment triangle pattern of motion to monitor the learning progress with more numbers of drawing attempts. A statistical analysis was then conducted to compare the selected kinematic features with the clinically validated normalised jerk. Two supervised machine learning models were finally developed to classify movement patterns and movement qualities based on the selected kinematic features. The study was based on data recorded from 14 participants using a single position sensor. 6 kinematic features were able to reflect sensitive changes during the experiment and all kinematic features contributed to the classification tasks. Consistent with the literature, the results indicated that features based on movement velocity were the most beneficial in the classification tasks.

Modelling and Design of Asymmetric Vibrations to Induce Bidirectional Force Sensation for Portable Rehabilitation Devices.

Assistive rehabilitation devices have been developed to help post-stroke patients to recover and live independently for a number of years. As a way to communicate with the physical world, force sensation is extremely helpful to rebuild neuroplasticity [1] during the rehabilitation process. This paper presents a model and design of asymmetric vibrations to provide bidirectional force sensation, which can be beneficial to design a portable rehabilitation haptic device. Users will feel a directional cue generated by asymmetric vibrations by holding the device. This directional cue can navigate users around in a rehabilitation training along with visual guidance and provide physical force sensations. The system consists of a current-drive single solenoid rigidly attached to a base. The system's model is verified through experiment at three different frequencies. Our analysis shows that by varying the signal's duty ratio, the direction of peak accelerations change from positive to negative. In addition, two other waveforms (saw-tooth and step-ramp) at several frequencies and different spring's stiffness are also discussed to determine the ideal characteristics of the input signal for rehabilitation applications.

Head-torso-hand coordination in children with and without developmental coordination disorder.

AIM: This study investigated the nature of coordination and control problems in children with developmental coordination disorder (DCD). METHOD: Seven adults (two males, five females, age range 20-28 y; mean 23 y, SD 2 y 8 mo) and eight children with DCD (six males, two females, age range 7-9 y; mean 8 y, SD 8 mo), and 10 without DCD (seven males, three females, age range 7-9 y; mean 8 y, SD 7 mo) sat in a swivel chair and looked at or pointed to targets. Optoelectronic apparatus recorded head, torso, and hand movements, and the spatial and temporal characteristics of the movements were computed. RESULTS: Head movement times were longer (p<0.05) in children with DCD than in the comparison group, even in the looking task, suggesting that these children experience problems at the lowest level of coordination (the coupling of synergistic muscle groups within a single degree of freedom). Increasing the task demands with the pointing condition affected the performance of children with DCD to a much greater extent than the other groups, most noticeably in key feedforward kinematic landmarks. Temporal coordination data indicated that all three groups attempted to produce similar movement patterns to each other, but that the children with DCD were much less successful than age-matched children in the comparison group. INTERPRETATION: Children with DCD have difficulty coordinating and controlling single degree-of-freedom movements; this problem makes more complex tasks disproportionately difficult for them. Quantitative analysis of kinematics provides key insights into the nature of the problems faced by children with DCD.

The coordination of upper and lower arm rotation.

We tested the hypothesis that the upper and lower arm act as a coordinative structure coupled through a higher order control system. Five healthy participants moved their hand between two targets in ten conditions via internal/external rotation of the shoulder. In eight conditions, the task required concurrent rotation of the lower arm (180 degrees pronation/supination). Movements were stereotypical within a condition but plotting the upper and lower arm angle against each other produced an asymmetrical pattern. With internal rotation, the upper arm reached peak angular velocity slower than the lower arm but this was reversed with external rotation. In two conditions, participants were asked to move faster and slower than their normal speed. The peak speed, time to peak speed and duration were predictable for the different tasks. Internal and external asymmetries decreased with faster movements. In addition a decrease in upper arm amplitude (from 90 degrees to 30 degrees) removed the asymmetry. The asymmetry was unaffected by initial posture but was exaggerated when external rotation was paired with pronation rather than supination, and internal rotation combined with supination (versus pronation). However, the presence of the same fundamental pattern suggests that the asymmetry is not due to biomechanical factors but might arise because of the difficulties involved in visually monitoring the hand when it is close to the body. The results support the idea that functional coupling can occur between upper and lower arm rotations and thus provides further evidence for a higher order control system which is responsible for coordination of arm segment movement.

Robots testing robots: ALAN-Arm, a humanoid arm for the testing of robotic rehabilitation systems.

Robotics is increasing in popularity as a method of providing rich, personalized and cost-effective physiotherapy to individuals with some degree of upper limb paralysis, such as those who have suffered a stroke. These robotic rehabilitation systems are often high powered, and exoskeletal systems can attach to the person in a restrictive manner. Therefore, ensuring the mechanical safety of these devices before they come in contact with individuals is a priority. Additionally, rehabilitation systems may use novel sensor systems to measure current arm position. Used to capture and assess patient movements, these first need to be verified for accuracy by an external system. We present the ALAN-Arm, a humanoid robotic arm designed to be used for both accuracy benchmarking and safety testing of robotic rehabilitation systems. The system can be attached to a rehabilitation device and then replay generated or human movement trajectories, as well as autonomously play rehabilitation games or activities. Tests of the ALAN-Arm indicated it could recreate the path of a generated slow movement path with a maximum error of 14.2mm (mean = 5.8mm) and perform cyclic movements up to 0.6Hz with low gain (<1.5dB). Replaying human data trajectories showed the ability to largely preserve human movement characteristics with slightly higher path length and lower normalised jerk.

Amplitude modulation drive to rectangular-plate linear ultrasonic motors with vibrators dimensions 8 mm x 2.16 mm X 1 mm.

In this paper, to exploit the contribution from not only the stators but also from other parts of miniature ultrasonic motors, an amplitude modulation drive is proposed to drive a miniature linear ultrasonic motor consisting of two rectangular piezoelectric ceramic plates. Using finite-element software, the first longitudinal and second lateral-bending frequencies of the vibrator are shown to be very close when its dimensions are 8 mm x 2.16 mm x 1 mm. So one single frequency power should be able to drive the motor. However, in practice the motor is found to be hard to move with a single frequency power because of its small vibration amplitudes and big frequency difference between its longitudinal and bending resonance, which is induced by the boundary condition variation. To drive the motor effectively, an amplitude modulation drive is used by superimposing two signals with nearly the same frequencies, around the resonant frequency of the vibrators of the linear motor. When the amplitude modulation frequency is close to the resonant frequency of the vibrator's surroundings, experimental results show that the linear motor can move back and forward with a maximum thrust force (over 0.016 N) and a maximum velocity (over 50 mm/s).

Employing the International Classification of Functioning, Disability and Health framework to capture user feedback in the design and testing stage of development of home-based arm rehabilitation technology.

The purpose of this study was to evaluate the International Classification of Functioning, Disability and Health (ICF) as a framework to ensure that key aspects of user feedback are identified in the design and testing stages of development of a home-based upper limb rehabilitation system. Seventeen stroke survivors with residual upper limb weakness, and seven healthcare professionals with expertise in stroke rehabilitation, were enrolled in the user-centered design process. Through semi-structured interviews, they provided feedback on the hardware, software and impact of a home-based rehabilitation device to facilitate self-managed arm exercise. Members of the multidisciplinary clinical and engineering research team, based on previous experience and existing literature in user-centred design, developed the topic list for the interviews. Meaningful concepts were extracted from participants' interviews based on existing ICF linking rules and matched to categories within the ICF Comprehensive Core Set for stroke. Most of the interview concepts (except personal factors) matched the existing ICF Comprehensive Core Set categories. Personal factors that emerged from interviews e.g. gender, age, interest, compliance, motivation, choice and convenience that might determine device usability are yet to be categorised within the ICF framework and hence could not be matched to a specific Core Set category.

The Cerebral Palsy Kinematic Assessment Tool (CPKAT): feasibility testing of a new portable tool for the objective evaluation of upper limb kinematics in children with cerebral palsy in the non-laboratory setting.

PURPOSE: Efficacy of treatment to improve upper-limb activity of children with cerebral palsy (CP) is typically evaluated outside clinical/laboratory environments through functional outcome measures (e.g. ABILHAND kids). This study evaluates CPKAT, a new portable laptop-based tool designed to objectively measure upper-limb kinematics in children with CP. METHODS: Seven children with unilateral CP (2 females; mean age 10 years 2 months (SD 2 years 3 months), median age 9 years 6 months, range 6 years 5 months, MACS II-IV) were evaluated on copying, tracking and tracing tasks at their homes using CPKAT. CPKAT recorded parameters relating to spatiotemporal hand movement: path length, movement time, smoothness, path accuracy and root mean square error. The Wilcoxon signed ranks test explored whether CPKAT could detect differences between the affected and less-affected limb. RESULTS: CPKAT detected intra-limb differences for movement time and smoothness (aiming), and path length (tracing). No intra-limb tracking differences were found, as hypothesised. These findings are consistent with other studies showing that movements of the impaired upper limb in unilateral CP are slower and less smooth. CONCLUSION: CPKAT provides a potential solution for home-based assessment of upper limb kinematics in children with CP to supplement other measures and assess functional intervention outcomes. Further validation is required. Implications for Rehabilitation This paper demonstrates the feasibility of evaluating upper limb kinematics in home using CPKAT, a portable laptop-based evaluation tool. We found that CPKAT is easy to set-up and use in home environments and yields useful kinematic measures of upper limb function. CPKAT can complement less responsive patient reported or subjectively evaluated functional measures for a more complete evaluation of children with cerebral palsy. Thus, CPKAT can help guide a multi-disciplinary team to more effective intervention and rehabilitation for children with cerebral palsy.

Feasibility of school-based computer-assisted robotic gaming technology for upper limb rehabilitation of children with cerebral palsy.

INTRODUCTION: We investigated the feasibility of using computer-assisted arm rehabilitation (CAAR) computer games in schools. Outcomes were children's preference for single player or dual player mode, and changes in arm activity and kinematics. METHOD: Nine boys and two girls with cerebral palsy (6-12 years, mean 9 years) played assistive technology computer games in single-user mode or with school friends in an AB-BA design. Preference was determined by recording the time spent playing each mode and by qualitative feedback. We used the ABILHAND-kids and Canadian Occupational Performance Measure to evaluate activity limitation, and a portable laptop-based device to capture arm kinematics. RESULTS: No difference was recorded between single-user and dual-user modes (median daily use 9.27 versus 11.2 min, p = 0.214). Children reported dual-user mode was preferable. There were no changes in activity limitation (ABILHAND-kids, p = 0.424; COPM, p = 0.484) but we found significant improvements in hand speed (p = 0.028), smoothness (p = 0.005) and accuracy (p = 0.007). CONCLUSION: School timetables prohibit extensive use of rehabilitation technology but there is potential for its short-term use to supplement a rehabilitation program. The restricted access to the rehabilitation games was sufficient to improve arm kinematics but not arm activity. Implications for Rehabilitation School premises and teaching staff present no obstacles to the installation of rehabilitation gaming technology. Twelve minutes per day is the average amount of time that the school time table permits children to use rehabilitation gaming equipment (without disruption to academic attendance). The use of rehabilitation gaming technology for an average of 12 minutes daily does not appear to benefit children's functional performance, but there are improvements in the kinematics of children's upper limb.

Performance improvement of rectangular-plate linear ultrasonic motors using dual-frequency drive.

To improve the performances of a rectangular-plate linear ultrasonic motor for specific applications, a dual-frequency drive has been proposed and investigated. Through careful design of the rectangular piezoelectric ceramic plate, its first longitudinal resonant frequency coincides with its second lateral bending resonant frequency and is one-third of its higher lateral bending resonant frequency. When a square-wave voltage is used to drive the motor, its first longitudinal and second bending and the higher bending vibration modes are excited. Experimental results show that the maximum thrust force and maximum velocity of the motor are over 170% of those obtained from the single-frequency sine-wave drive when the voltage performance of the motor becomes saturated.

A proof of concept study investigating the feasibility of combining iPAM robot assisted rehabilitation with functional electrical stimulation to deliver whole arm exercise in stroke survivors.

Rehabilitation robots can provide exercise for stroke survivors with weakness at the shoulder and elbow, but most do not facilitate hand movements. The aim was to combine robotics and functional electrical stimulation to facilitate exercise in stroke survivors with upper limb impairment. iPAM Mk II was used to assist active reaching in combination with an Odstock Pace stimulator to assist hand opening. The ABILHAND, Action Research Arm Test (ARAT) and the Stroke Impact Scale (SIS) were recorded at baseline and completion. Nine participants (eight males and one female; mean age = 58 years) were recruited; mean time since stroke was 16 months (range = 6-64). The ABILHAND at baseline was -2.73, improving to -1.45 at follow-up (p = 0.038). The ARAT changed from 4.1 to 2.6 (p = 0.180), and the SIS from 49 to 60 (p = 0.019). This study demonstrates that it is possible to combine two technologies in stroke rehabilitation.

The nature of arm movement in children with cerebral palsy when using computer-generated exercise games.

PURPOSE: To compare upper limb kinematics of children with spastic cerebral palsy (CP) using a passive rehabilitation joystick with those of adults and able-bodied children, to better understand the design requirements of computer-based rehabilitation devices. METHOD: A blocked comparative study involving seven children with spastic CP, nine able-bodied adults and nine able-bodied children, using a joystick system to play a computer game whilst the kinematics of their upper limb were recorded. The translational kinematics of the joystick's end point and the participant's shoulder movement (protraction/retraction) and elbow rotational kinematics (flexion/extension) were analysed for each group. RESULTS: Children with spastic CP matched their able-bodied peers in the time taken to complete the computer task, but this was due to a failure to adhere to the task instructions of travelling along a prescribed straight line when moving between targets. The spastic CP group took longer to initiate the first movement, which showed jerkier trajectories and demonstrated qualitatively different movement patterns when using the joystick, with shoulder movements that were significantly of greater magnitude than the able-bodied participants. CONCLUSIONS: Children with spastic CP generate large shoulder and hence trunk movements when using a joystick to undertake computer-generated arm exercises. This finding has implications for the development and use of assistive technologies to encourage exercise and the instructions given to users of such systems. IMPLICATIONS FOR REHABILITATION: A kinematic analysis of upper limb function of children with CP when using joystick devices is presented. Children with CP may use upper body movements to compensate for limitations in voluntary shoulder and elbow movements when undertaking computer games designed to encourage the practice of arm movement. The design of rehabilitative computer exercise systems should consider movement of the torso/shoulder as it may have implications for the quality of therapy in the rehabilitation of the upper limb in children with CP.

Health impacts of pedestrian head-loading: a review of the evidence with particular reference to women and children in sub-Saharan Africa.

Across sub-Saharan Africa, women and children play major roles as pedestrian load-transporters, in the widespread absence of basic sanitation services, electricity and affordable/reliable motorised transport. The majority of loads, including water and firewood for domestic purposes, are carried on the head. Load-carrying has implications not only for school attendance and performance, women's time budgets and gender relations, but arguably also for health and well-being. We report findings from a comprehensive review of relevant literature, undertaken June-September 2012, focussing particularly on biomechanics, maternal health, and the psycho-social impacts of load-carrying; we also draw from our own research. Key knowledge gaps and areas for future research are highlighted.

Reviewing the technological challenges associated with the development of a laparoscopic palpation device.

Minimally invasive surgery (MIS) has heralded a revolution in surgical practice, with numerous advantages over open surgery. Nevertheless, it prevents the surgeon from directly touching and manipulating tissue and therefore severely restricts the use of valuable techniques such as palpation. Accordingly a key challenge in MIS is to restore haptic feedback to the surgeon. This paper reviews the state-of-the-art in laparoscopic palpation devices (LPDs) with particular focus on device mechanisms, sensors and data analysis. It concludes by examining the challenges that must be overcome to create effective LPD systems that measure and display haptic information to the surgeon for improved intraoperative assessment.

Systematic review of outcome measures used in the evaluation of robot-assisted upper limb exercise in stroke.

OBJECTIVE: To classify and evaluate outcome measures currently used in robot-assisted exercise trials (RAET) in stroke, and to determine selection criteria for outcome measures in future trials. METHODS: Outcome measures used in RAET were identified from MEDLINE, EMBASE, CINAHL, PubMed and PsychINFO databases. The scale items were categorized into International Classification of Functioning Disability and Health (ICF) domains. The psychometric properties of scale were rated using a standardized pro forma. RESULTS: Thirty outcome measures were identified from 28 published RAET. Commonly used ICF body function scales were: Fugl-Meyer (FM) (24 studies), Modified Ashworth Scale (13 studies), Medical Research Council (11 studies), Kinematic measures (8 studies) and Motor Status Score (6 studies); ICF activity scale was Functional Independence Measure (FIMTM) (9 studies); ICF participation, personal and environmental factors scales were rarely used. Standard-ized rating identified that FM, kinematic measures, Action Research Arm Test, Wolf Motor Function Test, FIMTM, and ABILHAND have adequate measurement properties for use in RAET. CONCLUSION: Some of the currently used outcome measures seem appropriate for RAET. The use of the ICF framework enables selection of an appropriate combination of outcome measures depending on patient characteristics, such as severity of weakness and chronicity of stroke impairments.

Home based computer-assisted upper limb exercise for young children with cerebral palsy: a feasibility study investigating impact on motor control and functional outcome.

OBJECTIVE: We developed a home-based rehabilitation exercise system incorporating a powered joystick linked to a computer game, to enable children with arm paresis to participate in independent home exercise. We investigated the feasibility and impact of using the system in the home setting. METHODS: Eighteen children with cerebral palsy (median age 7.5 years, age range 5-16 years) were recruited from local National Health Service and the exercise system was installed in their home for approximately 4 weeks. Baseline and post-intervention assessments were taken: Canadian Occupational Performance Measure (COPM); kinematic measurement of movement quality (indexed by duration and smoothness) measured using a motion tracking system when performing a standardized computer task. RESULTS: The system was used for a median time of 75 min (interquartile range (IQR) 17-271), equating to 606 outward and 734 inward movements. Pre-COPM, (median 4.2); post-COPM (median 6.0); obs=34; z=3.62, p<0.01). Kinematic analysis of pre- and post-intervention movements on the standardized task showed decreased duration and increased smoothness. CONCLUSION: Some improvements in self-reported function and quality of movement are observed. This pilot study suggests that the system could be used to augment home-based arm exercise in an engaging way for children with cerebral palsy, although a controlled clinical trial is required to establish clinical efficacy. The feasibility of this technology has been demonstrated.