Collaborative Virtual Environments and Multimedia Communication Technologies in Healthcare

Maria Andréia F. Rodrigues1*, Raimir Holanda Filho2 Mestrado em Informática Aplicada, Universidade de Fortaleza - UNIFOR Av. Washington Soares 1321, J(30), 60811-905 Fortaleza-CE, Brazil 1*

[email protected], 2 [email protected] Tel: +55 85 3477-3268 Fax: +55 85 3477-3061

*corresponding author for author proof mailings

Collaborative Virtual Environments and Multimedia Communication Technologies in Healthcare Maria Andréia F. Rodrigues1, Raimir Holanda Filho2 Mestrado em Informática Aplicada, Universidade de Fortaleza - UNIFOR Av. Washington Soares 1321, J(30), 60811-905 Fortaleza-CE, Brazil 1 [email protected], 2 [email protected] Abstract:

We show how recent computing technologies such as collaborative virtual environments, high speed networks and mobile devices can be used for training and learning in healthcare providing an environment with security and quality of service. A number of studies have been conducted so far in these research areas. However, the development of integrated care has proven to be a difficult task. Therefore, we aim also to discuss the promising directions of the current work and growing importance on these subjects. This includes comparative analysis of the most relevant computer systems and applications developed so far that integrate modern computing technologies and health care. We believe this work is considered to be primarily for the benefit of those who are working in the field of computer science and health care, as well academic community, practitioners, and those involved in the development, implementation and study of integrated care using new computing technologies. Keywords: Collaboration, Virtual Environments, Multimedia Communication, Mobility, Network Security, Quality of Service, Healthcare Introduction In this chapter, we investigate how recent computing technologies such as collaborative virtual environments (CVEs), high speed networks and mobile devices can be used for training and learning in healthcare providing an environment with security and quality of service (QoS). In our view, there is a considerable gap between the promises that the new computing technologies hold, and the expectations that they cause in the medical area, particularly, in the simulation and training of surgical procedures. The evidences indicate that these expectations should be fulfilled in the next few years. This partnership will require the improvement of several computational technologies (storage devices, highspeed networks, distributed systems for mobile environments, etc), as well as changes in the background of health professionals before their routine adoption. New areas of interdisciplinary research can emerge, such as multimedia surgical support, interventional radiology, and even less invasive surgical procedures. The development of system architectures utilizing new computing technologies that support interactive computer

graphics and CVEs is another growing necessity. Examples are computer systems developed to support virtual training and learning, which are becoming more and more realistic (Blezek et al., 2000; Hosseini & Geordanas, 2001; Dev et al., 2002; Gunn et al., 2005a; DiMaio & Salcudean, 2005; Lee et al., 2006; Rodrigues et al., 2007). Some of these systems are used to construct a virtual world where users (trainer and trainees) can interact with one another and the environment in which they preside when performing training exercises. Nowadays, geographically distributed computing technologies can be interconnected to create an integrated computing environment. Healthcare professionals in different places can collaborate using this environment. Collaborative virtual environments involve several participants working in a network, using a shared virtual environment to analyze the same object from different points of view, and in which the action of any participant is viewed by all others sharing the environment. In order to make communications more realistic the environment must supply voice, video and data multimedia applications. This will favor comprehension of the actual intent of each participant, thus improving the collaborative environment. Networked computers and corresponding applications facilitate collaboration activities through a constellation of various tools (such as shared spaces, whiteboards, etc) having appropriate approaches to collaboration and social interactions. A World Wide Web tem proporcionado uma plataforma comum para que pessoas em qualquer parte do mundo possam interagir. Com o incremento do uso de dispositivos móveis, abre-se um vasto campo para novas pesquisas especialmente nas áreas de redes sem fio e colaboração distribuída. O aumento da disponibilidade de facilidades de comunicação tem provocado uma mudança no conceito de utilização de inúmeras aplicações, uma vez que dispositivos móveis possuem um comportamento diferente e oferecem possibilidades de interação diferentes, dependendo do contexto em que a aplicação está sendo usada. Para analisar estes diferentes cenários, muito esforço tem sido direcionado em pesquisas para mitigar possíveis ataques e para prover padrões mínimos de qualidade de serviço. The World Wide Web has provided a collective platform where people in any part of the globe can interact. The increasing number of mobile devices in use has opened a vast field for new research, especially in the areas of wireless networks and distributed collaboration. The increase in availability of communications facilities has brought about changes in the concept of use of many applications, considering that mobile devices have a different behavior and offer different possibilities of interaction, depending on the context in which the application is being used. In order to analyze these different settings, a lot of effort has been directed to researches in mitigating possible attacks, and providing minimum standards of QoS. Our discussion will also focus on recent wireless network technologies (Sharma & Nakamura, 2004) and mobility facilities (Pesch et al., 2007) that are highly recommended for the development of CVEs. One of the benefits of wireless data communication is the possibility of exchanging real-time messages among patients and medical staff. Wireless handhelds are becoming simple, direct and efficient communication paths with great potential for facilitating the access and flow of information. These new computing technologies are also important to be taken into account to provide better working conditions in the health area. Finally, as consequence of the use of patient data, further attention is important to provide a secure network environment, specifically in the cases where wireless connections

are used. In this scenario, authentication, authorization and cryptography procedures (Stallings, 2005) are mandatory to mitigate unauthorized users to get access to information, and to hinder data capture in promiscuous mode. Another relevant topic is to supply a network environment with minimum QoS guarantees for voice and video traffic (Ash, 2006). In this case, some network parameters such as delay and jitter are very important to assure QoS. Moreover, the traffic of huge image files should also be controlled in order not to affect real-time traffic classes. Hence, the key to achieving all these requirements on current technology is to pay more attention to applications that aim at assisting in bridging the gap between theoretical workers in the medical field and those scientists involved in handling and simulating true life problems. In so doing, the former should be able to better identify the objective towards which future developments should be directed, and the latter will be provided with an insight of the possibilities and limitations of existing theoretical work. Our utmost interest is then to investigate the extent to which present computer technologies can contribute to training and learning in healthcare. CVEs in Healthcare Although no attempt was made to be comprehensive, we have investigated the CVEs developed so far for training and learning in healthcare. Many researchers have reported that Virtual Reality (VR) technology has proved to be an invaluable approach in Computer Graphics to represent real life problems within an interactive three-dimensional representation of an environment. Based upon these grounds, we can consider that VR technology is increasingly becoming an important component for simulation in surgical training, although it brings with it educational issues and practical implications. Further, qualitative findings reported in the literature, present that simulators can provide safe, realistic learning environments for repeated practice, underpinned by feedback and objective metrics of performance (Kneebone, 2003). Some researchers have concentrated on the development of CVEs that have proved beneficial when groups or individuals need to share visual (graphics) or textual information. The most representative simulation-oriented learning environments support interaction, collaboration, and active learning. In general, the topics of training and learning are anatomy and basic surgical manipulations which involve a visual-haptic-audio experience. According to Dev et al. (2002), “while books, lectures, and multimedia are important routes to learning, the acts of touching, feeling, and cutting are believed to be essential in the training of surgeons”. Therefore, simulated environments that deliver this experience with simultaneous viewing of the virtual world by all users are expected to form the next generation of technology-enhanced training and learning environments. In some CVEs, haptic feedback devices are also used to improve the perceived virtual presence in these environments. In fact, they have been useful in building realistic computer based training systems in which users interact with virtual objects. In these systems, web-based technology can be used to set the model parameters and run the simulation on a remote machine, while visualizing results on a low cost local machine. A library of objects, such as patients and medical devices, can then be created, and used to provide the component parts for a variety of virtual environments (VEs) that may be shared, simulated, analyzed, touched, and visualized by the virtual world of trainee and instructor.

In the last few years, implementation of shared virtual environments has been particularly active. As a result, distributed, multi-user simulations have been implemented, which generally allow the interactions of users with the virtual scenario by clicking on objects to carry out functions to reproduce typical tasks and conditions commonly available in a physical training environment (e.g., a surgical) or educational environment (e.g., a classroom). These actions can be shared and transmitted through the Internet to other participants to have the impression of being involved in a training exercise. One example is the work presented in (Gunn et al., 2005b). Essentially, the main focus in implementing shared VEs that use haptic devices is to reduce delay in processing force information. Actually, touch is central in expertise in surgery. During surgery procedures, the surgeon should have the feeling in his hands of directly holding the medical instruments interacting with the patient. In addition, the integration of VR technologies and experiences with VR-based approaches for clinical assessment, treatment and rehabilitation offers powerful options that could revolutionize standard practices in these fields (Rose et al., 2005; Rizzo et al., 2006). There is a series of studies involving haptic devices which can display virtual textures, which are useful to perceive objects (tactile sensing). The haptic devices have potential for simulating real world objects and helping in the navigation of VEs, mainly for simulating minimally invasive procedures (to operate remotely and interactively) and assisting people with disabilities. The great importance of minimally invasive surgery resides in the fact that it has revolutionized many surgical procedures over the last few decades (Basdogan et al., 2004). One of the most important aspects of surgical simulation is to provide the user with estimated reaction forces that arise from surgical instrument and soft tissue interactions. The advantages of using VR in the medical area through simulations (that could replace the process of building physical mock-ups of functional environments needed for human performance testing, training, and learning) have already been recognized by many research groups. These joint efforts point to a promising future for CVEs. As the field of VR matures, our expectations are indeed that CVEs can deliver substantial benefits to the healthcare area. Mobility CVEs in healthcare increase the needs for privacy of data. This is tightly linked to security. If data about patients are to be processed, the level of security should match the sensibility of the data with personal information (e.g. address, phone number etc.) calling for lower security, and secret information (like names, exams, test results, etc) requiring highest security and more access restrictions. Enhanced privacy and security furthermore result in added trust in the system. This should in turn increase usage and acceptance, whereas low security will almost certainly have detrimental effects. Hence, the system needs to be secure. The necessity and the level of security depend on the data processed. Patient images and other medical content could be secured in a way that only authorized users (health staff) have access to them. This might be desirable from a medical point of view when the documents should not be widely distributed, for example, because they contain confidential information. Recently, security concerns have been emphasized due to mobility issues, and due to access through wireless networks. Introduction of these new technologies have

associated greater difficulties to these kinds of communications, demanding mechanisms, for example, to prevent attacks. In order to provide mobility, wireless network technologies have expanded rapidly in the past few years, becoming accessible to the ordinary user, which may revolutionize the computing and learning environments. This concept affords the emergence of numerous possibilities, like the development of real-time, distributed collaborative applications in mobile devices. The concept of mobility in CVEs is not entirely new. For example, a system was proposed in Satchel (Lamming et al., 2000) to provide access to any document, at any time from anywhere. Although this is not a Mobile-CVE, it requires sharing of resources from anywhere at any time. The scenario proposed in Satchel involved a worker outside his workplace, who needed remote access to documents, but couldn’t do so effectively due to the high transmission times provoked by mobility. Satchel’s scenario (Lamming et al., 2000) demonstrates the importance of resource (e.g. documents) sharing during the mobile process, and that it is even more important to diffuse the collaboration of not only resources, but also of information in the more ample sense of the word (such as chats, messages, etc.). The new “computing anywhere, at any time” paradigm is generating a movement towards mobile services. In this case the concepts of e-commerce are being extended to mcommerce, and e-learning now includes m-learning. With mobility, advantages in the quality of education, and improved results in learning are both expected. M-learning is, therefore, the next step in the evolution of e-learning. The need for mobile users to use mobile devices for collaborative purposes does not arise from the fact that they are mobile, but from the implication of mobility, that is, they do not have access to conventional means of collaboration through their desktop computers. As mobile devices and access networks become more adequate and trustworthy, people feel increasingly attracted to use collaborative computing on several types of platforms. These changes have brought about a transition from the traditional model of computing to an ubiquitous one, which enables the entire environment to be available to the user from wherever it may be required. The use of mobile devices is also justified in emergency situations, where a worker (or team of workers) must be located to establish collaboration, but is presently outside the normal work environment, and therefore unable to access his (their) desktop computers. Therefore, it is necessary to evaluate the impact of transferring the use of a desktop computer to a mobile device, mainly in the issues related to QoS (quality of service) and security. Now we present some situations in the medical field where mobile devices can be employed: requests for a second opinion, remote attendance of surgical procedures, and the transmission of warnings concerning the state of patients. New computing technologies have provided some tools to overcome some limitations, creating virtual environments that can bring people closer together. A fairly common procedure, nowadays, is the concept of a “second opinion”. This procedure has progressed from the use of asynchronous communications (e-mails) to synchronous communications, by means of instant messages to relay information. More recently, this communication has progressed even further with the development of CVEs that allow healthcare workers to interact in real time with audio, video and data transfer based on Web standard interfaces. All of these concepts may obviously be available also in PDA (Personal Digital Assistant) type mobile devices, and the collaborators can be located

anywhere, at any time. This has been made possible through the creation of an access infrastructure based on wireless networks. It was recently established that part of the resistance of healthcare professionals to working in remote areas originates from the feeling of isolation and not being able to share diagnoses. In the case of transmission of patient data warnings, the idea is not limited to the use of Short Message Services (SMS) provided by cellular phone networks, but also the transmission of a warning followed by the relay of information that can be monitored at a given moment, allowing a physician to evaluate the gravity of the warning and issue procedures adequate for each case. Quality of Service and Stability Present Internet network architecture was designed to relay information using a Best Effort service model, with no guarantees concerning QoS (quality of service) requirements. In the event of a congestion packets are discarded and there is a certain downgrade in the transmission rate, which does not guarantee that the application will be executed effectively. These problems result from the increase of traffic over the Internet, and the type of information carried over the network. QoS is defined as a set of techniques used to provide differentiated treatments to the flow of data, according to the application. The requirements for each flow can be characterized by four main parameters: Delay – the time necessary for a packet to travel through he network, measured from the moment of transmission to the moment of arrival; Jitter - is the variation in delay, and is defined by consecutive pairs of packets (if Di is the delay of the ith packet, then the jitter of the pair of packets is defined as Di - D(i-1)); Reliability - is associated to the packet loss rate, which is the relation between the number of packets lost and the number transmitted, measured at the receiving end (this loss occurs when the router buffer is overloaded and no longer allows storage of packets); Bandwidth – represents the speed of the environment, in other words, the maximum transmission rate available at a given moment for communication between two knots of the network (Ash, 2006). In a multimedia environment different types of traffic (viedo, voice, data, etc.) compete for the use of the same resources. Therefore it is important to understand the network requirements needed to provide satisfactory QoS performance. The introduction of QoS management mechanisms is necessary, as a measure to guarantee that applications sensitive to delay, jitter and packet loss are not affected. Furthermore, to guarantee the continuous use of a mobile system, stability must be a premise. Stability, in the technical sense, means that the services must be carried out obeying parameters of speed and availability. This is a fundamental point when the link to the mobile device has low speed. Instability, in this case, such as connection losses and application interruptions, will cause loss of user data. If the system is functioning devoid of interesting information, users will lose interest in the system. Lastly, stability is also connected to maintenance. Programming errors may never be fully solved, thus the need for someone who is responsible for receiving bug reports and suggestions that should be incorporated to the system, in order to guarantee good acceptance.

Mobile Learning The premise of Mobile-education is based on the idea by Pascoe et al. (2000): “Using While Moving”, which is basically what users need from a mobile computer system. Mobile-education affords distributed collaboration over wireless devices to generate learning opportunities. This is, therefore, a new approach that uses a virtual wireless community to facilitate learning activities through collaboration in a distributed environment. Mobile-Education is significantly different from traditional learning systems. In this new model collaborative activities are based on virtual communities, and offer a wide range of collaboration opportunities, such as synchronous and asynchronous peer-topeer interactivity, allowing data visualization. All of this interaction will be possible from handheld devices. Main Challenges Some challenges facing the CVEs and Multimedia Communication Technologies are briefly outlined in this section. High performance computing and networking technology promise to offer great potential to link many medical centers and universities to each other. An interesting point to note regarding this fact, is that virtual anatomical models of the human body will be able then to be shared and used systematically, for various surgical simulation and learning applications through the Web. As a result, we believe that these applications will be able to generate immersive and highly adaptable VEs that will allow individual participants or teams to train and learn simultaneously. However, we need also to take into account the fact that CVEs are typically associated with high-performance computers and specialized input/output haptic devices, with high costs involved, which make operating them on a large scale still prohibitively expensive. Also, related to this issue is the problem of ensuring that each participant sharing an entity in the CVE has a consistent view of the environment. The consequences of differing state can be detrimental to the application as each user’s perception of the interaction being performed would differ, thus, leading to a breakdown in the collaboration (Glencross & Chalmers, 2005). Other important issues in typical CVEs are the most complex types of interactions possible, which are collisions (detection and response) and touch. Collisions are often the bottleneck of simulation applications in terms of calculation time, directly related to the geometric complexity of the VE, and sometimes involves a huge number of geometrical tests for determining which elements are colliding (Ericson, 2005). Colliding virtual bodies can be deformable or rigid. During their movements, a point located anywhere in space (centre of rotation) is associated with the surfaces. Rotational and translational velocities around that point define the instantaneous motion. These velocities are integrated forward in time to define the motion of the surfaces. It is appropriate to certify always during the collisions whether the surfaces are still both physically continuous and topologically contiguous. From a rendering point of view, for graphical display of VEs that support interactions between objects, such as collisions, one of the most important considerations is maintaining suitably high frame rates to guarantee the quality of the simulation. In some CVEs, participants may change attributes of entities (with complex behavior), which have physical characteristics allowing them to deform or flow (Glencross & Chalmers, 2005). This type of interaction impacts upon the values provided to the

algorithms used to compute the state and/or the geometric structure of the entities. Haptic feedback is one of the important stimuli that can be used to provide richer response for physical interaction with VEs by touch. However, simply adding haptic feedback to CVEs does not lead to usable medical applications. It is also essential to consider how to combine suitable force models to support correct perception of surface details (e.g, textures), entityentity collisions, and motion during interactions. As medical devices are becoming increasingly networked, ensuring the same level of existing health safety become crucial (Lee et al., 2006), especially considering that interactions in VEs still suffer from problems of accuracy. In addition, networked virtual reality (NVR) services with integrated multimedia components (and perceived “real-time” interactivity) impose certain QoS requirements at the user/application level as well on the underlying network (Skorin-Kapov et al., 2004). IP technology, in its original conception, does not offer any type of guarantee of QoS. Also, in order for an IP network to support voice services with strict delay and jitter requirements, it is necessary to implement some functionalities to this protocol. The IETF (Internet Engineering Task Force) standardized two specific architectures to supply QoS in the IP environment: IntServ – Integrated Services, and DiffServ – Differentiated Services. The big challenge, however, consists of implementing an infrastructure capable of supporting these architectures. Further, as devices become increasingly smaller in physical terms, but larger in software terms, they bring capabilities that are sufficient to provide the basis for mobile use. Equipped with small health applications these PDAs can be given out to a number of health agents, thus providing a higher coverage by giving many agents access to a computing device. Therefore, as mobility in collaboration is emerging as a research topic in itself, it is imperative that researchers in this field explore new methods of interaction and novel applications (Perry et al., 2001). The type of device which can be used for a service is basically unrestricted as long as it is wireless. However, wireless does not mean that a constant connection to a server or network is required. A PDA that holds notes which were transmitted during synchronization using a personal computer is a mobile device just as is a mobile phone with a Wireless Application Protocol (WAP) browser, or a PDA with a Wireless Local Area Network (WLAN) connection. The need for privacy and confidentiality is giving rise to increased expectations about data storage and transmission security, as data on demand emerges as a viable concept in healthcare. Regarding security, it is important to emphasize that unrestricted admittance is only possible with a valid user identity, which is controlled by the system. Adequate security is ensured by encrypting all data at 128 bit. For mobile admittance the user has to enter an identifier. When the infrastructure supports Wireless Identification Module (WIM), additional security can be established by unambiguously identifying a user. Acknowledgements The research was partly supported by The National Council for Scientific and Technological Development of Brazil (CNPq) under grant No. 303046/2006-6.

Conclusions and Future Work The medical field has been one of the most appealing areas for computer graphics and VR research. Further, we believe that CVEs can provide novice physicians, residents and students with a natural training and learning environment that may increase understanding of the anatomic relationships of the human body and improve healthcare, minimizing the risks to patients, thereby their ultimate safety. The advantage is that the novice, for example, will be introduced to uncommon conditions that would only arise rarely in clinical practice. We also observe that while a range of VR medical applications do contain simulation and rich behavior to varying degrees, it is still very hard to quantify the realism of the computer models, since the human body is a system of complex interactions between organs and tissues. These interactions are particularly intricate in the case of soft tissues (very little information is currently known regarding their deformable behavior). In addition, there are ethical problems involved and the need of volunteers. Last, but not least, there is still the fact that collecting medical data takes time. Beyond these issues are also the psychological and sociological barriers to implementation that any new technology should overcome. Crossing these barriers among professionals in Education, Training, Healthcare Delivery, Engineering, and Computer Science will require an integrated and collaborative approach. Actually, over the past few years, a movement characterized by increased collaboration among these professionals has started to take shape. QoS makes it possible to offer better guarantees and security for Internet applications, once the traffic of advanced applications (such as voice, videoconference, etc.) is being given greater priority, while users of traditional applications continue to use the Best Effort approach. Finally, we hope that CVEs and recent computer technologies can contribute not only to the advance and improvement of healthcare delivery, but also to do it more safely. References Ash, G. (2006). Traffic Engineering and QoS optimization of integrated voice & data networks. Morgan Kaufmann Series in Networking. Basdogan, C., De, S., Kim., J., Munivandi, M., & Srinivasan, M.A. (2004). Haptics in minimally invasive surgical simulation and training. IEEE Computer Graphics and Applications (special issue on Haptic Rendering – Beyond Visual Computing), vol. 24, 2, pp. 56-64. Blezek, D.J., Robb, R.A., & Martin, D.P. (2000). Virtual reality simulation of regional anesthesia for training of residentes. Presented at the 33rd Hawaii International Conference on System Sciences, pp. 1-8. IEEE CS Press. Burdea, G. (1999). Haptic Feedback for Virtual Reality. Presented at the Virtual Reality and Prototyping Workshop, pp. 87-96.

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Rodrigues, M.A.F., Silva, W.B., Barbosa-Neto, M.E., Gillies, D.F., Ribeiro, I.M.M.P. (2007). An interactive simulation system for training and treatment planning in orthodontics (article in press, doi: 10.1016/j.cag.2007.04.010). Computers & Graphics, Elsevier. Rose, F.D., Brooks, B.M. & Rizzo, A.A. (2005). Virtual reality in brain damage rehabilitation: a review. CyberPsychology & Behavior, vol. 8, 3, pp. 241-262. Skorin-Kapov, L., Vilendečić, D., Mikić, D. (2004). Experimental performance evaluation of networked virtual reality services. Presented at the IEEE MELECON, pp. 661-664. IEEE CS Press. Sharma, C., & Nakamura, Y. (2004). Wireless data services: technologies, business models and global markets. Cambridge University Press. Stallings, W. (2005). Cryptography and network security. Prentice Hall. Terms and Definitions Virtual Reality (VR): VR entails the use of advanced technologies, including computers and multimedia peripherals, to produce “virtual” environments that users perceive as comparable to real world objects. It offers great potential as a technology for computerbased training and simulation. It may be delivered to the user via a variety of input/output devices such as screen monitors, head-mounted displays, data gloves, etc. Virtual Environments (VEs): VEs can be used to simulate aspects of the real world which are not physically available to the users of the application. Collaborative Virtual Environments (CVEs): CVEs are used to construct a virtual world where users can interact with one another and the environment in which they preside in order to perform, for example, a training exercise. Distributed Collaboration: VR has been employed to allow geographically distributed people to do more than simply hear and see each other. For instance, VR technology is being used to develop highly interactive shared virtual environments, graphically orientated, for local and distance training and learning. Haptic Feedback: A crucial sensorial modality in VR applications. Haptics means both force feedback (simulating object hardness, weight, inertia, etc) and tactile feedback (simulating surface contact geometry, smoothness, slippage, and temperature) (Burdea, 1999). Haptics: It refers to technology which interfaces the user via the sense of touch by applying forces, vibrations and/or motions to the user. Mobility: It is the ability of mobile devices to move or change the position.

Wireless: communication or transfer of information over a distance without the use of wires. It is generally used for mobile devices. Quality of Service (QoS): QoS refers to control mechanisms that can provide different priority to different users or data flows, or guarantee a certain level of performance to a data flow in accordance with requests from the application program. Security: It is the practice of protecting and preserving private resources and information on the network from unauthorized modification or destruction.