Download Virtual Reality as a Complementary Therapy

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.
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