PARREHA – Assistive Technology for Parkinson’s Rehabilitation R. Greenlaw1, D. Wessel2, N. Katevas3, F. Andritsos4, D. Memos5, A. Prentza6 and U. Delprato7
1 Project Description 1.1 History PARREHA (PARkinsonians’ REHAbilitation) is an EU funded R&D project (5th Framework Programme, Information System Technologies) undertaken by five European technology firms, the EU’s Joint Research Centre and EUROPARK, a European organisation for people with Parkinson’s disease. The project started on 1st January 2000 and will conclude on 31st December 2002.
1.2 Objectives PARREHA is concerned with the assessment of motor performance and the design of therapeutic exercises for people with Parkinson’s disease (PD). The system will run from normal PCs and will offer virtual-reality exercises which can be tailored remotely and supervised by video-conferencing. Additionally the virtual-reality unit is portable and can be used offline. The intention is to provide a means by which people with Parkinson’s can remotely access health care professionals, assess their disease stage and enjoy appropriate, interesting therapy and increased mobility. Although several motion disorders could benefit from this system, PD 1
Oxford Computer Consultants Ltd, 2 Cambridge Terrace, Oxford OX1 1RR, UK EUROPARK, Haneckstr. 31, D-65719 Hofheim, Germany 3 ZENON, Kanari 5, 15354 Athens, Greece 4 Joint Research Centre, EU, 21020 Ispra, Italy 5 Advanced Technologies in Business, 707 High Road, London, UK 6 National Technical University Athens, Zografou Campus H/Y Bldg, 15773 Athens, Greece 7 T&T, Via Nalde 45, Roma, Italy 2
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was selected because PD specialists are so scarce in comparison to the numbers of patients and because PD patients can react so strongly to audio-visual cues (Riess, 1999; Lewis et al., 2000). Although PD is primarily treated pharmacologically, patients can be helped by a variety of adjunct therapies (Jahanshahi, 1998) some of which are suitable for telemedicine. The following is a possible example of the use of PARREHA. A person with PD at home or in a local clinic could link to a medical specialist at an agreed time. They will have a TV-quality video-conferencing link so they can see and speak to each other as normally as possible. The patient wears a light virtual reality “headset” providing audio-visual cues to aid their motion (such as stripes on the floor) or to practise moving in difficult situations (such as through a virtual doorway or crowd). The specialist can ask the patient to perform exercises and can tailor the virtual environment to assess and improve the patient’s performance. Since the person with PD has a wearable PC they can use the tailored audio-visual cues to increase their mobility out of the home. (Several PD patients have expressed an interest in a “pair of glasses” that would enable them to walk during “off” phases.) This project has been of especial interest to people with vascular Parkinson’s for which no drug therapy exists.
2 Progress 2.1 First Prototype Providing Visual Cues A simple prototype was built which displays visual cues (vertical blue and horizontal pink stripes) into a headset via a laptop PC. The headset was the semitransparent Sony Glasstron so the subject can view the real and virtual worlds together (augmented reality).One subject with PD, unable to walk, could walk and carry the PC using the prototype (see accompanying MPEG video).
Figure 1. Prototype visual cues from a laptop PC being tested
Although the prototype was successful for a small number of subjects all users expressed difficulty using the equipment which was heavy, technologically intimidating and socially isolating. For this reason ways were sought to make the
PARREHA–Assistive Technology for Parkinson’s Rehabilitation
equipment more ergonomic and to remove the need of the user to wear a headset that covers most of their face.
2.2 Second Prototype Providing Visual Cues Xybernaut (http://www.xybernaut.de/), a manufacturer of wearable PCs and head mounted displays agreed to supply the project with suitable hardware. This allowed PARREHA to explore a truly wearable solution in which visual cues are presented to the user over one eye via a small monitor mounted on a headset. To increase the field of view the monitor points away from the user and is reflected back into one by via a fixed mirror. Informal tests organised by the Bad Nauheim Parkinson’s clinic, Germany and EUROPARK have shown that the Xybernaut system can produce a dramatic improvement in gait in a minority of people with PD. Further work is needed to quantify this population.
Figure 2. Prototype visual cues from wearable PC being tested
2.3 Telemedicine It is known that PD individuals vary considerably in their reaction to the audio and visual cues. It is therefore envisaged that the cues generated should be easily tailored, possibly in the user’s home via a remote link. To date this exercise tailoring software has been prototyped and videoconferencing links established. The exercise tailoring software now needs to be integrated into the videoconferencing so that the exercise can be control remotely with for a user at home. At the Bad Nauheim clinic we have experimented extensively with videoconferencing between speech- and physiotherapists and patients with Parkinson’s. We have not quantified our results at this stage but both groups reported rapid acceptance of therapy via video-conferencing providing the sound and picture quality is good (comparable to television), in agreement with Hubble et al. (1993).
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Deterioration of the quality and/or any technical problems rapidly leads to users abandoning the technology. A study of the cost-effectiveness of therapy via videoconferencing compared to face-to-face therapy was performed. It was found that at present costs tele-therapy is only likely to be favoured if multipoint videoconferencing is available. With current household equipment this is unlikely to be of sufficient quality. However, the reported popularity of videoconferencing provided strong qualitative evidence that teletherapy will become attractive in the future, especially given the high overall costs of Parkinson’s treatment (Dodel et al., 1999).
2.4 Virtual Reality Exercises One partner (Zenon) has extended the provision of virtual cues to the generation of an immersive virtual room in which people with PD can practise moving in difficult situations, such as narrow doorways, optionally with visual cues to help them. This feature has only recently been implemented using a CyVisor head mounted display and Flock-of-Birds magnetic motion tracker. An example of the type of exercise environment envisaged is shown in Figure 3 (generated by an earlier prototype). There is a mixture of “positive” cues to help the user (stripes on the floor) and “negative” cues they can practise against (a narrow doorway).
Figure 3. Example virtual room
2.5 Future Work The remaining development will include the integration of telemedicine and videotherapy facilities with the virtual reality exercise tools. The Department of Neurology, University of Marburg, Germany will then perform clinical trials on the final device. The Parkinson’s Clinic, Bad Nauheim, Germany has agreed to test the remote therapy aspects and provide user involvement.
PARREHA–Assistive Technology for Parkinson’s Rehabilitation
3 Acknowledgements T. Riess and S. Weghorst from the Human Interface Technology Laboratory (“HIT lab”), University of Washington advised PARREHA at the project launch. They have considerable experience using a similar portable aid to walking for people with PD (see http://www.hitl.washington.edu/projects/parkinsons/ ). Xybernaut GmbH, Otto-Lilienthal-Strasse 36, D71034 Böblingen, Germany kindly provided the “Mobile Assistant” hardware described above (http://www.xybernaut.de/). Professor Henneberg, Parkinson Fachklinik, Bad Nauheim, Franz-Grödel-Str. 6, 61231 Bad Nauheim, Germany provided staff time and resources for user involvement tests at the Bad Nauheim clinic.
4 References Dodel RC, Eggert K, Oertel WH (1999) Economical research on Parkinson’s disease: a review of the literature II. European Journal of Neurology, 6 (suppl 2): S3-S15 Hubble JP, Pahwa R, Michalek DK, Thomas C, Koller WC (1993) Interactive video conferencing: a means of providing interim care to Parkinson’s disease patients. Movement Disorders, 8(3):380-382 Jahanshahi M, Mardsen CD (1998) Parkinson’s disease: a self-help guide for patients and their carers, Human Horizon series, Souvenir Press Lewis GN, Byblow WD, Walt SE (2000) Stride length regulation in Parkinson’s disease: the use of extrinsic visual cues. Brain, 123(10): 2077-2090 Riess T (1999) Visual cues and Parkinson’s disease, Report R-99-10, University of Washington, http://www.hitl.washington.edu/publications/r-99-10//r-99-10.pdf