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Virtual Reality as a Complementary Therapy Faten S. Alrashed 430203305 Hind T. AL Hashimi 430202983 Computer Science Department King Saud University KSU Riyadh, Saudi Arabia [email protected] Computer Science Department King Saud University KSU Riyadh, Saudi Arabia [email protected] Abstract—Treatment of any type of disease depends mainly on patient’s psychology as well as conventional therapy. In term of pain, it is usually related strongly with patients psychology and need for conscious attention. Earlier literature reported that patients can control there symptoms and pain related disease if they can make their thought away of their disease. Virtual Reality is a wellknown technique used to distract patients' thoughts away and boost his or her self-esteem and confidence. This result in tremendous improvement in patient’s mind and inner feeling. Which clinically improves the immune system. Virtual Reality is considered as a complementary psychological therapy used in conjunction with conventional therapy. This kind of therapy creates a computer-based virtual world for patients to cope with their diseases and experience better life. Many VR environments were developed and tested such as Snow world and Spider world to help patient manage their pain and fear. and expensive process, it still rudimentary. Also, in term of usage, there are some difficulties. Virtual reality may cause some side effects on patients. It can induce, like disorientation, dizziness and nausea [2]. Although, numerous case studies have been conducted, but still there is a lack of good quality, longscale study on the effectiveness of virtual reality as a complementary therapy [6]. This paper will focus on the effect of virtual reality technique as a complementary treatment along with its advantages and disadvantages. In the sections below, we first provide a brief overview on the VR technology and complementary therapy. Then we'll discuss the effect of virtual reality as a complementary psychological intervention on different kind of patients by providing a set of conducted studies on this area. Then, we'll clarify the performance criteria and the results. After that, we are going to highlighting the advantages and disadvantages of such technique in the medical area. Finally, we conclude with a summary, results around whether virtual reality has an positive effect on the patients psychology or not, and suggestions for future research. Throughout this paper the acronym VR will be used to refer to virtual reality. This paper discusses the effect of virtual reality as one of the complementary therapies which distracts patients attention away from their pain. Keywords-virtual reality; pain management; complementary therapy I. INTRODUCTION Nowadays Virtual Reality becomes one of the most interested technologies used in the medical area as a complementary treatment. Virtual Reality as a therapy is viewed as a complementary psychological intervention when used in conjunction with conventional therapy. This kind of therapy creates a virtual world for patients to cope with their disease by immersing themselves in this computer generated world [1], [2]. During the past years, many researches and studies have been conducted to prove the positive impact of virtual reality on different kind of patients[3],[4]such as relieving stress, depression, anxiety symptoms for breast cancer patients, so helping them to cope with chemotherapy[5]. indeed, a number of clinics -such as Vision Counselling- are already establish using this technique for e.g. panic attacks, quit smoking, weight loss, pain management, performance anxiety. However, virtual reality in the medical area suffers from various drawback including technical limitations. Virtual world development is complicated II. BACKGROUND A. VIRTUAL REALITY TECHNOLOGY Virtual reality technique is a type of humancomputer interaction refers to any computer-based virtual world created by special tools, such as Quest3D, to simulate the real world for immersing user in 3Dvirtual environment by using devices such as head mounted display HMD, gloves, suit, and many other. Virtual Reality become one of the most interested subject in the mid of 1980s. It was hit the headlines as well as a number of conferences, studies, and different media programs were born to discuss the meaning of virtual reality [7]. Today, VR has m.any applications in different area and often in a confusing and misleading manner, such as the simulation of environment for training and education purpose, as well as for imagination and game designing. VRML is a standard file format for modeling and representing 3-dimensional (3D) interactive graphics with integrated hyperlinks. It allows to create "virtual environment" networked via the Internet and hyperlinked with the World Wide Web. Today, VRML has been superseded by X3D [8]. Users can interact with the virtual world through a head-mounted display, stereo-earphones, a position sensor, a controller such as a joystick or speed wheel and output devices. In the SnowWorld virtual environment, which created to relieve burn patient's pain, patient wear a headset and manipulate a joystick, to maneuvers through the program. Other application called SpiderWorld, designed to help phobic patient over come their fear of spider. In this virtual environment patient supposed to wears a headset that shows a virtual tarantula, and gloves to touch this virtual tarantula. Other applications may use different VR equipment to achieve their goal [1]. B. COMPLEMENTARY THERAPY IN BRIEF The term complementary therapy refers to the practices, systematic and comprehensive concepts of health and disease, diagnostic and therapeutic procedures, in medical treatment, which is differ from the conventional treatments [9]. A complementary therapy is used in conjunction with traditional therapies for different goals. It includes Yoga Massage therapy, Herbal remedies, Naturopathic medicine, and many others. As reported by Jane [10], Complementary therapies could be excellent for pain management. Also Caroline Hoffman concludes that complementary therapy has an effective impact on reducing the distress of symptoms and side-effects associated with breast cancer and its treatments, as well as the psychoemotional aspects of coping with this traumatic experience [11]. VR considered to be one of the one of the most required method as an complementary therapy. This technique is used to employ the power of the mind. In other words, VR therapy refers to imagining in order to have a positive influence on the body. VR in the medical area focuses on: Help patients to cope with hard therspy e.g. chemotherapy. The amount and effectiveness in controlling pain. Positive influence in the outcome of surgery. improve patient quality of life. III. LITERATURE REVIEW Virtual reality can treat and relieves pain in different situation of patients. It can ease pain physically and psychologically. Also; it can create therapeutic environments for the evaluating and treatment of medical conditions and to support exposure of anxiety disorders. The treatment makes the patient into a virtual environment that contains the feared situation rather than making the patient into the actual environment. The hardware used in virtual reality program would be 3D Head Mounted Display, Head Tracker and a 3D Controller. The 3D Controller can be used by the patient to move forwards, backwards and side to side in the virtual environment. Schneider an Workman [4] observed, the extension of virtual reality effectiveness in reduction of distress symptom during chemotherapy for cancer patients. Study has been conducted with 12 children, divided into two groups: VR group, and control group. Results showed, a significant decrease on a symptom distress scale immediately following the treatment (chemotherapy plus virtual reality distraction) for virtual realty group. 82% of participants said that the usage of virtual reality with chemotherapy was better than any other treatment, and all participants would like to use virtual reality equipment again. No body indicated that the virtual reality made them feel worse. This was the first study conducted to test the effectiveness of virtual reality for cancer patients receiving chemotherapy. Hunter G. Hoffman [1], worked on several burned patients with unbearable pain and relieves their pain by using virtual-reality program during wound treatment. Patients using virtual reality just for 15 to 20 minutes during wound care sessions to take their mind off their pain. They're completely isolated from watching their wound care and they can't hear the other sounds and they're in Snow World. The results 35 to 50% reductions in pain during wound care and a few hospitals are now explore the use of virtual reality as a tool for pain control. Peretz B, Bimstein E [3], evaluates the effects of imagery suggestions during administration of local anesthetic in pediatric dental patients. They were chosen eighty children between the ages of three and sixteen years and who required at least one injection of local anesthesia. Before the injection and during the first treatment session, each child asked to choose favorite image. After that patients asked to visualize the same image throughout the injection procedures. The results was imaging techniques may be successfully used in the administration of local anesthesia to children from three years of age to reduce mitigate untoward, pain-related stress. For breast cancer, in most cases patients infected with states of stress, anxiety, fatigue, and other psychological symptoms, as a results of diagnosis and treatment. This lead to inability of the body to coping with treatment. Susan M. Schneider and Linda E. Hood [4], explore virtual reality (VR) as a distraction intervention to relieve pain in adults taking chemotherapy treatments for breast, colon, and lung cancer. Participants were randomly chosen from 123 adults to receive the VR distraction intervention during one chemotherapy treatment and then received no intervention during an alternate matched chemotherapy treatment. The results was Patients had changing perception of time (p < 0.001) when using VR and believed that head mounted device easy to use and 82% of them will be used VR again. The treatment of Patients that using VR made shorter and chemotherapy treatments with VR more tolerable and better than treatments without the distraction intervention. Lazarus and Folkman [4], defined the ability of body to cope with something as: cognitive and behavioral efforts to coping with certain external or internal factors. This capability reflects the ideas and activities used by human to manage fatigue states going through it. Lazarus and Folkman said in their theory that two types of strategies with distinct coping functions exist, those directed at: Managing or altering the problem (problemfocused coping) or Regulating the emotional response to the problem (emotion-focused coping) e.g. distancing, changing thoughts, making positive comparisons, and finding positive value in negative events. Based on this theory, Susan et al. [4] considered that chemotherapy is a matter causing stress, in contrast, the distraction techniques is the strategy used to regulate the emotional response. So, measuring the extension of virtual reality effectiveness as a distraction tool to relieve chemotherapy symptoms side for breast cancer patients, was the subjective of this study. Two hypotheses were tested by researchers. The first was that women diagnosed with breast cancer will have significantly lower symptom distress, fatigue, and anxiety levels immediately following an IV chemotherapy treatment during which they receive a virtual reality distraction intervention than they would with no virtual reality intervention. The second was that women diagnosed with breast cancer will have significantly lower symptom distress, fatigue, and anxiety levels 48 hours following an IV chemotherapy treatment during which they receive a virtual reality distraction intervention than they would with no virtual reality intervention.20 women with breast cancer have been participated, aged 18-55. They were scheduled to receive IV chemotherapy in two periods. The participants have been divided into two groups. The first group consisting of : category (A) the participants received the virtual reality treatment during their first chemotherapy treatment (during period 1), and category (B) the participants received the virtual reality treatment during their second chemotherapy treatment (during period 2). The second group received standard care without any type of intervention. In this study, virtual reality equipments were as follow: headset to projects an image with corresponding sound, in addition to a computer mouse to manipulate image. About the environment, patients chose from three scenarios included deep sea diving, walking through an art museum, or solving a mystery. Each scenario lasts several hours. There were some important factors that the study focused on and measured such as: distress, fatigue, anxiety symptoms occurred to patients because of diagnoses and treatment, and patients opinions about using virtual reality environment. Special instruments have been used to measure these factors: Symptom Distress Scale (SDS). Revised Piper Fatigue Scale (PFS). Evaluation of Virtual Reality Intervention. Symptom Distress Scale, have been developed by Ruth McCorkle and Young (1978). It is an indicator used to identify the symptoms faced by cancer patients. it measures the occurrence of such symptoms and thus gives overall result of the symptom of stress. Fatigue Scale (Piper et al., 1998) is an indicator to determine the degree of fatigue by measuring behavioral/severity, affective meaning, sensory, and cognitive/mood. This indicator is composed of 22 items scaled from 0 to 10, where greater levels of fatigue indicated with higher scores. Also some questions are included to provide qualitative data. Evaluation of Virtual Reality Intervention is an open-ended questioners that was used to learn about patients' opinions about the intervention. The idea of this evaluation is revolve around the ease of equipment use, length of time the equipment was used, scenario choices, effectiveness of virtual reality as a distractor, and desire to use virtual reality during future treatments. Result of this study show that both of the hypotheses have been proved as follow: Significant reduction in the rate of distress and fatigue scale of the patients, who used virtual reality technology, immediately postchemotherapy. Reduction in the rate of distress and fatigue scale of the patients, who used virtual reality technology, 48 hours post-chemotherapy, see figure1. Responses to open-ended questionnaire expressed descriptive data which indicated the ease of using virtual reality equipments by participants, and they hadn't any strange feeling through using the intervention. All participants preferred to use virtual reality with chemotherapy, and 95% of them would like to use the intervention again. Susan M. Schneider et al [12], explored the effects of a virtual reality distraction intervention on chemotherapy related symptom distress levels in 16 women aged 50 and older. The head-mounted display was used to display images and block competing stimuli during chemotherapy treatment. Participants were randomly chosen to receive the VR distraction intervention during one chemotherapy treatment and then received no intervention during an alternate matched chemotherapy treatment. Women thought that head mounted device was easy to use and 100% would use VR again. Hiroshi Oyama [13], described several VR researches for palliative medicine at the National Cancer Center Hospital Japan. VR provide patients with emotional support and make them to assume positive life against cancer. VR research in palliative medicine is useful because it represents not only an enhanced human-machine interface, but enhanced human communication technology. The results of VR in palliative medicine is(1) to support communication between the patient and others, (2) to provide psychological support to treat neurosis and help to stabilize the patient's mental state, and (3) to actually treat cancer. a b Figure1 (a)Symptom Distress Scale and (b) Revised Piper Fatigue Scale IV. PERFORMANCE CRITERIA AND RESULTS Measuring level of pain for patients after each VR session which is called a "Measure of Assessing Pain", this is a global measure of ten degrees which help patient care provider assesses pain according to different patients. The scale starts at 0 (no pain) to 10 (pain in the worst case) for patient self assessment. Face and behavioral scales can be used to express patient's pain that cannot assess his/her pain intensity, Figure2 [14]. Figure2:Pain Assessment Scale In the field of medical complementary treatment VR considered to be one of the best technologies for distraction used by psychologists. It could be used before, during or after the traditional therapy, according to patient's situation and diseases, for pain management figure3[1]. Hoffman et al [1], used pain stimuli on healthy volunteers. The results of functional magnetic resonance imaging showed large increases in activity in several regions of the brain that are known to be involved in the perception of pain. But when the volunteers involved in a virtual- reality environment during the stimuli, the pain-related activity drawn. Some studies conclude that VR effectiveness has not proved enough. These studies state that virtual reality as a distraction technique in the field of medical treatment requires more experiments with large number of samples. The results of virtual reality pain distraction have been unusually strong and consistent results, and the results obtained by Hoffman with his team at HTLAB have been independently replicated by burn centers in other countries. So far, two or three studies have shown results in the predicted direction that were not very impressive in magnitude, but they used a less immersive VR system than what recommended. Hoffman is confidents that if these same researchers used a high quality VR system and software, they would show much stronger VR analgesia. For example, in one laboratory study conducted by Hoffman, 1 out of 3 participants showed clinically meaningful reductions in pain during VR. That’s fairly impressive. But in that same double blind study, 2 out of 3 subjects randomly assigned to receive a wide field of view VR helmet showed clinically meaningful reductions in pain! That’s a massive improvement in VR analgesia, just by using good VR system (the problem is that the cheap helmet costed only 2K, and the high technology helmets now cost about $35,000 U.S. dollars. But such high prices should come down during the next five years or so (The cost of a good VR helmet will probably drop to 15K within the next five years) [15]. Figure3 Pain Related Brain Activity Usually, breast cancer patients spend many hours in clinic treatment, while receiving chemotherapy, which leads to weariness and sometimes depression. It has been observed that the use of virtual reality greatly help in reducing and speed up the time[4], figure4 . Figure4 Perception of Time While Using VR V. CHARACTERISTICS OF IMMERSIVE VR VR technology has a number of positive characteristic which can be summarized as follow [8]: The ability of VR'S HMD to view the environment as a natural or real environment. It is allow for looking around, walking around, and even flying in the virtual environment. The powerful anthropomorphism of object enhances the perception of depth and the sense of space. The virtual environment relates to the people size properly and provides realistic interaction through the use of gloves and other devices which allow to control, operate, and manipulate it. The auditory, haptic, and other non-visual technologies could enhance the full immersion in the virtual world. All of these properties enhance the effectiveness of VR as a distraction technique and hence increase its power in alleviating pain. VI. CHALLENGES As stated by Hoffman [15], the challenges for VR pain distraction that faced them during their work are availability, cost and ruggedness of virtual reality goggles. The VR HMD that is most effective for pain distraction currently 90 degree diagonal field of view (big eyepieces that stimulate a lot of peripheral vision to help maximize the illusion of going inside the computer-generated world). Such high technology VR HMD tend to be very expensive, and at least with Rockwell Collins HMD, the miniature displays in the HMD often break, which is expensive to fix and takes a long time to fix. High technology VR HMD typically takes a long time to buy even if you have the money. HMD have been very frustrating. Recently a new HMD came on the market, and so far it has not broken! The manufacturer of this new HMD sold us another HMD many years ago, that never broke, so we are hoping this new manufacturer fixed the problem of excessively breakable VR HMD. Many burn patients found it uncomfortable to wear a VR HMD on their head, and this was especially true for patients with severe burns on their head or face. Furthermore, even if patients don’t have serious burns on their head or face, the conventional high technology VR HMD tends to weigh nearly 2 lbs. So just the weight itself can become uncomfortable. For sterility reasons, keeping the helmet scrapped in disposable plastic. And head tracking has been a pain in the neck. So, stop using head tracking, and have invented a goggle holder is more comfortable solution. The robotlike arm holds the goggles near the patients' head, so they don’t have to wear the VR helmet on their head. That was an important breakthrough that has made virtual reality goggles easier to use [15]. Another Challenge is that many burn patients receive their painful medical procedures while sitting soaking in a bathtub, and/or while having water sprayed onto them. This water makes it dangerous to wear a conventional VR HMD, so we have had to avoid using VR during wound care in the scrub tank. We temporarily solved this problem long enough for one small research study. Hoffman has designed and built a special VR HMD that uses light, no electricity, so patients could wear the helmet while sitting in a bathtub of water, no problem. That worked really well, but Hoffman only made one water-friendly VR HMD. We are in the process of designing a new water-friendly VR HMD that could potentially be more widely used [15]. There are a number of challenges related technical rezones. Modeling of the 3d objects, defining their behavior and interaction manner, defining object texture and other properties such as degree of reflectance, shininess, and connect all of these with the environment. These processes are time consuming. Makin VR technology unavailable easily[2]. VII. RISKS AND SAFETY ISSUES Some patients suffer from a number of symptoms when they attempt to received their therapy. Stanney [16] pointed out some potential risks associated with virtual reality therapy. Stanney states that, people who suffer from panic attacks, those with serious medical problems such as heart disease or epilepsy, and those who are (or have recently been) taking drugs with major physiological or psychological effects, are subjects for psychological risks. Max et al [17], from virtual reality laboratory of Clark Atlanta University, argues with the solution of excluding those having such a situation. Gregg L et al [18], in his literature review refer to the possibility of having disadvantages of using VR technology in term of side effect in the field of mental health treatment. He concluded that, till now there is no adequate research proves the effectiveness of using VR in the medical treatment. If burn centers use the VR equipment that recommended by psychologists, the results have been strong. One possible side effect of VR simulator sickness, a form of motion sickness. But, Hoffman's team has not had any problem with simulator sickness, because their software was specifically designed to minimize visual stimuli likely to lead to simulator sickness. For example, patients move slowly through the virtual world, along a pre-defined pathway. So they do not have to navigate around in SnowWorld, and they go slow, and they are discouraged from looking around too fast [15]. VIII. CURRENT APPLICATION AND FUTURE WORK Nowadays, VR technology is actually used in a number of medical centers, and hospitals e.g. Hartford hospital which provides several VR simulations. Virtual Reality Medical Center, provides a set of VR programs which successfully treat more than 300 patients suffering from phobias and anxiety disorders. For victims of 11 Sept. who suffer from some emotional problems such as post-traumatic stress disorder (PTSD), NewYork-Presbyterian/Weill Cornell medical center conducted two new studies offer virtual reality therapy. Since 2002, NewYorkPresbyterian/Weill Cornell medical center provide the therapy for the first time and it proved the effectiveness and successfulness of the therapy on 11 Sept related PTSD[19]. After the great results they obtained in the initial clinical trial from 2006 – 2009 U.S. Army Institute of Surgical Research and Army Burn Center is now working on the second clinical trial of SnowWorld virtual world mentioned above, to distract burn patients while they undergo excruciating burn treatment and physical therapy[20]. For Iraq and Afghanistan veterans with PTSD, Barbara Rothbaum et al, is currently conducts study funded by the National Institute of Mental Health (NIMH). They test the combination of the drug dcycloserine (DCS) with virtual reality therapy to help alleviate the symptoms of PTSD[21]. Hoffman with his team have been designed a number of hardware and software improvements that they predict will further enhance the effectiveness of virtual reality therapy. For example, Eric Seibel, who is a member of the team has designed a miniature projector that can be used as the image source in VR goggles in the future. Currently, the team are in the process of trying to get funding to develop new VR goggles that use this new display technology. These new goggles will be lightweight, and can be used near water[15]. The team also have designed a new version of the virtual reality software. The new software is designed to be effective for a longer time, and is designed to be used day after day by the same patient. (currently trying to get funding for the new software)[15]. In the future, if research documents any long term benefits to better acute procedural pain management, insurance companies may realize the financial advantage of virtual reality pain distraction, and help cover costs of providing VR analgesia (in addition to traditional pain medications)[15]. IX. CONCLUSION During the past years, the number of studies and research, talking about psychological and social problems faced by patients and their need of psychotherapy, are increased. Psychotherapy has several methods, which varying depending on the results of their effectiveness and impact, and how the patient accepts it. It has been found that the distraction technique was one of the best psychotherapy methods, while it have the ability to attract patients attention to things which was convenient to them. Imagery therapy is a kind of distraction technique, which can relieve physical symptoms such as pain, fatigue, and distress, as well as psychological symptoms such as uncomfortable feelings. Virtual reality considered to be one of the successful imagery as well as complementary methods that helps patients to cope with their pain. it's defined as a way to immersed mind and body into a computergenerated environment in a naturalistic fashion. Virtual reality is interactive, and it engages several senses simultaneously. These characteristics made virtual reality to be one of the best distraction techniques comparing with other complementary therapy such as humor and relaxation therapy. Pain require attention VR lores the attention away from a pain and leaves less attention available process pain. REFERENCES [1] Hunter Hoffman, Virtual Reality Therapy, Scientific American Magazine, August 2004. [2] Caroline Derksen. (2007, November 16). Virtual reality: Technology and Treatment of Anxiety Disorder (no edition) [Online]. Available: http://www.slais.ubc.ca/courses/libr500/07-08wt1/www/C_Derksen-WWW/index.htm. [3] Peretz B and Bimstein E, "The Use of Imagery Suggestions During Administration of Local Anesthetic in Pediatric Dental Patients," 2000. [4] Susan M. Schneider, and Linda E. Hood,"Virtual Reality: A Distraction Intervention for Chemotherapy," Oncology Nursing Forum Journal, 2007. 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[18] Gregg, L. & Tarrier, N. (2007). Virtual reality in mental health: A review of the literature. Social Psychiatry, 42, 343-354. [19] "New Studies Offer Virtual Reality Therapy for Psychological Victims of Sept. 11," NewYork-Presbyterian Hospital/Weill Cornell Medical Center, Sep.2006. [20] "Virtual Reality Helps Combat Burn Victims Through Wound Care Treatment". American Academy of Pain Medicine (AAPM) 26th Annual Meeting. February 15, 2010. [21] Kathi Baker, "Study Uses Virtual Reality Therapy for Iraq and Afghanistan Veterans with PTSD," Sep.2010.