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Virtual Reality MRI:
Playful Reduction of Children’s Anxiety in MRI Exams
Stefan Liszio
University of Duisburg-Essen
Entertainment Computing Group
Duisburg, Germany
stefan.liszio@uni-due.de
Maic Masuch
University of Duisburg-Essen
Entertainment Computing Group
Duisburg, Germany
maic.masuch@uni-due.de
ABSTRACT
Many people, especially children, perceive MRI exams as
threatening. They experience anxiety and stress during the
procedure. Often this results in premature termination of the
scan or low image quality. To avoid these adverse effects, it
is common to sedate anxious patients. We present a playful
virtual reality (VR) application for children (8 - 15 years) to
counter anxiety and avoid sedation. Our approach uses a real-
istic virtual MRI scanner for desensitization and habituation to
the MRI exam. To compensate the limited amount of profound
knowledge about the design of child-tailored VR applications,
we pursued a child-centered design process. Starting with
expert interviews, we iterated through several development
cycles and carried out focus group testings to evaluate proto-
types of the VR application. Then, we conducted a field study
with 13 patients under real life clinical conditions. Although
results were non-significant, tendencies indicate a drop in the
anxiety level after using the application. Furthermore, the ap-
plication received strong support of the participating children,
and medical professionals.
ACM Classification Keywords
H.5.1. Information Interfaces and Presentation (e.g. HCI):
Multimedia Information Systems: Artificial, augmented, and
virtual realities; K.8.0. Personal Computing: General: Games
Author Keywords
VR gaming; stress; magnetic resonance imaging;
child-centered design; sedation; patient preparation;
desensitization.
VIRTUAL REALITY IN HEALTHCARE
Today’s VR technology is capable of presenting highly realis-
tic simulated experiences while being relatively inexpensive.
By providing simulated stereoscopic images and synchroniza-
tion of head movements, it is possible to elicit high levels
of sensory immersion [32]. The higher the level of sensory
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DOI: http://dx.doi.org/10.1145/3078072.3079713
immersion, the more likely it is for a recipient to experience
presence, that is, the feeling of actual being in the virtual
world [14]. Thus, VR allows the recipient to experience virtual
worlds as if they were real. These worlds represent completely
controllable environments, which can be explored safely and
independently of time and place. Consequently, VR has been
applied in a multitude of domains related to healthcare, such as
for graded exposure therapy of anxiety disorders, but also for
education, and training of surgical skills [22, 1]. It has been
shown that confronting patients with specific feared stimuli in
immersive virtual environments is an effective way to reduce
anxiety [26]. Thus, virtual reality exposure therapy (VRET)
has proven to be suitable for a variety of affective (especially
anxiety) disorders like specific phobias (e.g. claustrophobia,
fear of heights, fear of flying, PTSD, social phobia) [43, 41].
VRET addresses some of the disadvantages of classical in vivo
and imaginal exposure therapy approaches: Unlike in vivo ex-
posure, VRET is independent from time and space, and can
be performed in a safe environment without the risk of public
embarrassment [43]. In contrast to imaginal exposure, VRET
does not require imaginative abilities of the patient to visual-
ize the anxiety-evoking scenario. Furthermore, a remarkable
amount of research has been done in applying VR-technology
to support distraction therapy in pain management [36]. Hoff-
man et al. [15], the pioneers of this approach, used a VR
game to distract patients from pain during woundcare. With
functional magnetic resonance imaging, the authors were able
to show that VR as a distraction technique is successful and ef-
fective in reducing pain perception. Several follow-up studies
have reinforced these findings also for chronic pain [42].
Although some authors have already anticipated the potential
of VR as a method for preparing individuals for stressful situ-
ations [43, 34], to our knowledge, this is the first attempt to
systematically design and use a playful VR application for the
reduction of children’s anxiety and stress related to magnetic
resonance imaging (MRI). We present an approach which com-
bines patient information, play-therapeutic elements, games,
and VR exposure in one VR application for desensitization
and habituation to both the MRI examination procedure and
the MRI scanner itself prior to the actual scan. To design
this application in accordance with the needs and preferences
of the target group, we followed an iterative child-centered
design process.
PATIENT’S FEAR OF MRI EXAMS
The number of MRI units and exams is rapidly increasing
worldwide [25]. MRI technology has improved diagnosis and
treatment and is, in the current state of knowledge, physi-
cally less harmful compared to conventional radiography and
computed tomography. However, some patients, especially
children, experience the MRI exam as threatening. Thus, they
react with expressions of anxiety and stress [30]. Some au-
thors report that up to 30% of patients experience high levels
of anxiety during the examination [12]. Klonoff, Janata and
Kaufman [16] estimate that 20% of the patients undergoing
an MRI exam exhibit claustrophobic reactions. The reasons
are manifold, some are related to the specific characteristics
of the MRI scanning procedure, others relate to internal fac-
tors. Fear-inducing factors attributed to the MRI unit and the
examination procedure are, among others, spatial narrowness
of the scanner tube, unfamiliarity with the surrounding and
the medical equipment, the noise, or the duration of the scan
and the necessity of lying motionlessly [12, 30]. Among the
internal factors are the unfamiliarity with the situation, the
anticipation of pain and discomfort, a sense of being not in
control of the situation, and worries about the diagnosis [12].
Some patients have reported feeling “buried alive” or “aban-
doned” [12]. Children are particularly prone to these negative
feelings because they lack understanding of the situation and
instructions [30]. Thus, it is likely that they respond with
sometimes extreme stress reactions. These stress reactions are
highly problematic because movements of the patient result
in motion artifacts, which impede the diagnosis. Indeed, Mal-
isza et al. [21] reported a failure rate of at least 50% when
performing MRI studies with children aged 2 to 5 years, and a
failure rate of 35% for children aged 6 to 7 years. Furthermore,
the duration of the examination increases with lacking patient
compliance and the procedure becomes more unpleasant for
the patient [12]. Such negative experiences may also result in
procedure-induced traumas and phobias [12]. Stressed patients
show increased susceptibility for infections, increased sensa-
tion of pain leading to a higher need for analgesics subsequent
to the treatment [40] as well as delayed wound healing [24].
Refusal to undergo the scan and premature termination cause
adverse health consequences and a serious waste of resources
[6]. Sedation or general anesthesia (GA) are commonly ap-
plied to improve patient cooperation and thus image quality
[7]. However, sedation and GA can have several physiolog-
ical impacts on the function of heart, lung, and circulatory
system as well as a higher risk for patients with accompany-
ing diseases [40]. The aforementioned problems emphasize
the advantages of non-pharmacological strategies to help anx-
ious patients to cope with the threatening situation. Such
interventions can either be applied prior to the MRI exam as
preventive measures or during the scanning procedure, like the
performance of relaxation techniques [39], distraction from
the fear-inducing stimuli [11], or the presentation of mood
enhancing audio-visual cues [5]. Proper patient preparation
is considered a well-received preventive measure making the
actual examination more comfortable for pediatric and adult
patients, and leading to a higher probability of successful scan
completion and increased image quality [16, 30, 7].
STRATEGIES FOR PATIENT PREPARATION
Among several non-pharmacological methods to prepare the
patient for the MRI exam and to reduce anxiety, the use of
information material such as brochures, flyers, or films is the
most common. Törnqvist et al. [38] reported that 4% of the
MR images of patients receiving information material prior to
the examination showed motion artifacts compared to 15.4%
of the images of patients not receiving such material. For
children there are some books on the topic of MRI exams
(e.g. [10], [31]). These books use stories and metaphors com-
monly used in conventional children’s books to explain the
process of MRI scans or how MRI machines work. However,
books cannot give a real-life impression of the noises and the
narrowness of the MRI tube. Even illustrated books cannot
address experiential factors of the MRI exam. Hence, books
or other informational material is often used supplemental
to other strategies for anxiety reduction but has to be edited
and presented in a child-tailored manner, for instance as a pic-
ture book. Especially young children may have problems in
transferring the content of the book to the real life experience,
though. However, to our knowledge, there is no empirical
validation of the efficacy of children’s books in reducing antic-
ipatory or acute anxiety related to MRI exams.
A more sophisticated strategy to prepare young patients is to
use elements of play-therapy to help children familiarize with
the forthcoming exam. Pressdee et al. [28] showed that a
play-therapeutic session prior to the MRI exam reduced the
need for sedation or anesthetics. Bharthi et al. [4] were able
to replicate these results in a randomized controlled trial with
children aged 4 to 10 years. Both studies applied comparable
procedures. At first, patients and caregivers received detailed
information regarding the MRI exam in easy understandable
language from a play-therapist. In a second step, a small
model of the MRI unit was used to accustom the child to the
visual appearance of the machine. The characteristic sounds
and noises of the MRI were played at increasing volume.
Subsequently, the children were asked to choose their favorite
toy and place it in the scanner. The children were instructed
about the importance of being motionless during the scan.
They were encouraged to stand as still as possible. If a child
was able to stand still for 5 minutes (which is the average
time of a single MRI sequence [4]), the training session was
considered to be successful. Finally, the children were asked
to reenact the MRI examination procedure with the toy to
support their sense of control of the situation.
Another promising but far more time-consuming and complex
method is to provide young patients with the opportunity to
explore the MRI scanner and the examination room itself prior
to the actual scan. Therefore, some hospitals own practice
or Mock MRI units. Such Mock MRI scanners consist of
only the shell of the machine without the magnets or any
electronics. Several studies demonstrated that simulations of
MRI scans with Mock MRI scanners could reduce anxiety
in pediatric patients. Children who otherwise would have
received sedation or GA were able to successfully complete
the MRI exam after practicing [30, 7, 6]. Barnea-Goraly et al.
[2] showed that even a simple and inexpensive toy tunnel can
be utilized to simulate an MRI exam and to increase success
rates significantly. Play-therapy and practice with Mock MRI
scanners provide the most lively and realistic experience to
children. Such training sessions allow gradual approximation
to the fear inducing stimuli, though they are costly in time
and resources. A therapist or medical staff member has to be
around to instruct and guide the child. Hospitals need to have
the necessary space, materials, and a simulator available.
Due to the limitations of these approaches, Wiederhold and
Wiederhold [43] suggest creating a simulated MRI scanner
using VR technology. In VR, users can visit and explore places
that are not easily accessible in reality. Thus, we assume that
a VR application can help patients to experience an MRI
scan prior to the actual exam and to become familiar with the
process and the medical environment.
VIRTUAL REALITY FOR CHILDREN
Research on the systematic design of child-tailored VR-
systems, i.e. the hard- and software for operating VR ap-
plications [9], is still limited. The specific developmental
characteristics of children have diverse implications for the
design of both VR hardware and VR software. Head-mounted
displays (HMD) like Oculus Rift or HTC Vive represent state-
of-the-art VR hardware and are available for a broad consumer
market since 2016. While these HMDs need to be connected
with wires to a high-end PC, wireless solutions are preferable
for child-tailored VR in terms of safety for the child and the
equipment. Google Daydream and Samsung Galaxy VR are
prominent examples for a family of smartphone based VR
displays. The smartphone is used for processing and display-
ing the virtual world and is worn in front of the face with a
special head-mount. The mobility of such HMDs comes at the
expense of processing power, display resolution, field-of-view
as well as the need for an internal power supply compared to
wired HMDs. With regard to product design and ergonomics,
most currently available HMDs target at adult users, ignoring
the special physical demands of children [13]. For instance,
head circumference is growing with age [35]. Together with
the weight of the device, this can be problematic for both
comfort and safety reasons [13]. Robinson [29] reports that
children experienced the Oculus Rift as being too heavy and
felt uncomfortable after wearing the device for a longer period
of time. Furthermore, interpupillary distance (IPD), i.e. the
distance between the centers of both pupils, varies between
individuals and depends on age, gender, and ethnicity [8].
Since IPD is a determining factor for stereoscopic sight, it
is necessary that a child-tailored HMD is adjustable even for
lower IPD values. Children are more sensitive to restrictions
in the field-of-view in HMDs than adults and have difficulties
in orienting and navigating in a virtual world [23]. This is
due to their inability to abstract the world and gain knowledge
about their route. Speaking of immersion and presence, some
research indicates that young children are more likely to ex-
perience higher levels of presence than adults [13]. Recent
research of Baumgartner et al. [3] with children aged 6-11
used functional magnetic resonance imaging technology to
analyze activity of certain brain regions while the participants
received a fully immersive virtual environment. The results
indicate that both left and right dorsolateral prefrontal cortex
(DLPFC) moderate the experience of presence in adults, while
the authors did not find activity in these structures in children.
This is due to the fact that the DLPFC is not fully matured in
younger ages. Concerning direct physiological effects of VR
consumption in children, i.e. simulator sickness, our observa-
tions show that children are less prone to simulator sickness
than adults are. However, there is only little scientific research
on this topic, but some indications that age is not an indicator
for VR related nausea or discomfort [13].
APPROACH
Anxiety and stress are closely related phenomena, where anx-
iety is the emotional component of a stress response to a
stressor (i.e. a stress inducing stimulus) [37]. In order to find
a solution to reduce children’s anxiety as an outcome of stress,
we need to understand how stress arises. According to the
transactional model of stress and coping developed by Lazarus
[18], stress is a result of reciprocal adjustment processes of
the individual to the environment, that is, the individual ac-
tively affects the environment and the environment affects the
individual’s behavior [27]. Hence, the individual is actively
involved in the occurrence of stress and the stress reactions.
Central to this model is the cognitive appraisal of the stressful
event (primary appraisal) and the available resources (sec-
ondary appraisal). Thus, whether a stimulus is perceived as
stressful depends on its meaning for the individual and the
existence of suitable resources to react to or cope with the
stimulus. Stress results, if the stimulus is appraised as poten-
tially harmful or threatening and the resources as insufficient.
In this case, coping processes are triggered. These coping
processes can be either problem-oriented or emotion-oriented.
Problem-oriented coping strategies can be applied if the indi-
vidual is able to control the situation. Otherwise, the individual
has to use emotion-oriented strategies. As the name of this
model indicates, this process of appraisal and coping is dy-
namic. After a coping strategy has been applied, a reappraisal
of the stimulus happens and the process starts again. Based
on these assumptions, interventions to prevent stress – and
consequently anxiety – can have two starting points: Either
they address the primary cognitive appraisal of the stimulus
or they provide suitable coping strategies to the individual.
Our approach focuses on a change in the primary cognitive
appraisal of the potentially threatening characteristics of MRI
exam and its context using child-tailored VR technology. More
precisely, we integrate elements of play-therapy and desen-
sitization in a playful VR application incorporating games
and narrative components. Hence, we fuse patient prepara-
tion methods, which have been proven to be anxiety reducing
with the advantages of VR and digital games. The applica-
tion aims at the prevention of stress and anxiety of children
undergoing an MRI exam in general. Additionally, it can be
used as an intervention for children who have expressed such
reactions in prior MRI exams. As pointed out before, typical
potentially stress-inducing stimuli can be divided into two
categories, such as unfamiliarity with the environment and the
characteristics of the MRI unit (e.g. spatial narrowness, noise,
necessity to lie motionlessly) on the one hand, and experiential
stress-inducing factors on the other hand. The child’s lack of
understanding of the procedure, uncertainty, the anticipation of
Figure 1. The application is structured according to the phases of play-therapeutic strategies to reduce anxiety prior to MRI exams (lower row).
Screenshots from the prototyp in the upper row demonstrate the virtual MRI scanner and the environment as well as the characters (b-c). Pictures a)
and b) depict two of the implemented games, while e) shows the view of the user when she is moved into the virtual MRI scanner.
pain, or the feeling of not being in control of the situation are
informational factors possibly leading to anxiety and stress.
Experience
A virtual MRI scanner and examination room presented in
VR can provide patients with the opportunity to explore the
unknown environment in advance. Thanks to the high quality
of sensory immersion of modern VR-systems, it is possible
to create a natural simulation of an actual MRI scan. The use
of a realistic VR MRI scanner and records of the real MRI’s
characteristic sounds and noises help to make the patient feel
present in the virtual scanner. Furthermore, patients can use
the application at any time and from any location, at home
or even from their hospital bed. If they do feel too anxious,
the virtual exploration can be easily interrupted without any
organizational limitations. Likewise, it is possible to repeat the
exploration as often as desired. Thus, the application can be
used for desensitization and training of the whole procedure.
Information
Informational stress factors can further be addressed with the
use of VR by presenting information about the MRI exam in
a child-tailored and interactive way, interwoven with story-
elements. Proceeding through the story, the child learns, for
instance, about the purpose of an MRI, how it works, that it is
noisy but harmless, and what the coils are for. The story helps
the child to gain an understanding of the procedure, while
the protagonists demonstrate how to behave, encourage, and
motivate the child [19, 13]. Therefore, it is necessary to design
characters the child can identify with [20], supporting empathy
and involvement.
Games
Besides experience and information, we use the pleasing and
motivating effects of games to further educate the children and
to elicit positive emotions like fun and joy. As Lazarus and
Abramovitz [17] have shown with their emotive imaginary
technique, children’s fears can be systematically reduced by
the induction of positive emotions. Comparable to system-
atic desensitization, the child is guided to imagine situations
which elicit emotions that are incompatible with anxiety. This
technique is based on the effect of reciprocal inhibition as
described by Wolpe [44], that is, an anxiety reaction is ei-
ther completely or partly inhibited, if an emotional response
incompatible to anxiety (e.g. anger, relaxation) is evoked.
According to Lazarus and Abramovitz [17], a rapid and sus-
tainable change of the child’s emotional experience can be
achieved with this technique.
CONCEPT AND IMPLEMENTATION
The theoretical approach presented in the previous section
builds the foundation for the concept of our playful VR appli-
cation, which aims at the reduction of anxiety and stress of
children aged 8 to 15 years who await an MRI exam. Before
going into more detail about the elements of the application
in the following subsections, we introduce its basic structure.
The application follows four steps as in play-therapy: (1) In-
formation, (2) observation,( 3) modeling, and (4) exposure.
Additionally, it incorporates several methods to desensitize
children for the upcoming medical examination using game
elements (Figure 1). We created a virtual MRI examination
room with a realistic animated MRI scanner as well as a virtual
preparation room. After a short introduction to the story and
its protagonists follows a tutorial, which teaches the user the
controls and the basic interaction concept. (1) Subsequently,
information about the MRI exam and the scanner itself are
provided by the application’s narrative elements and several
interactive objects which are common in this domain. Fur-
thermore, a simple game teaches the child which items can be
taken into the MRI scanner and which not. (2) Following, in
the observation phase, the child enters the virtual MRI room
and is acquainted with the virtual MRI unit. The steps of the
MRI scanning procedure are explained using the example of
the story’s protagonists. (3) In the subsequent modeling phase,
the child is encouraged to reenact these steps in a second game.
(4) In the final exposure phase, the child is invited to experi-
ence a virtual MRI scan in VR. A further game challenges the
child not to move for five minutes. The application ends with
a short conclusion of the story.
Pretest and First Design Lessons
In order to ensure the optimal fit of the application to the
needs and preferences of the target group, we followed an
iterative child-centered design process [20], that is, the active
participation of children as representatives of the target group
in the different stages of the application development. Children
can provide valuable insights and information to inform the
design process and thus should be involved in the development
phases as equal partners, informants, and testers [13]. Thus,
in a first step, we created a short interactive story a as VR
application for Google Cardboard and presented it to two
boys (both 7 years old) and three girls (10 years old). We
conducted an explorative and unstructured interview, to learn
how they react to and think about VR. Furthermore, we gained
knowledge about possible usability and ergonomic issues. The
most urgent question for us was whether the children would
feel present in the virtual world and if the story would be
absorbing, even though the used VR hardware does not offer
a high level of immersion. The feedback from all young
testers was positive. The children were very interested in
the technology and wanted to know how it works. While
following the story, the testers intuitively looked around in the
virtual world and explored every detail actively. They showed
positive emotions and expressed joy and amusement in their
verbal expressions. Some children highlighted the feeling of
being inside the world as what they liked most. Moreover, all
children were completely absorbed while playing and did not
react to any event or noise in the surrounding. However, in this
first test, a standard Playstation 3 game controller was used as
input device for movement and action in the VR application.
Although all children stated to know the controller, some had
problems in finding the right buttons since they were not able
to see them. The testers criticized wearing comfort of the
Google Cardboard head-mount used in this testing because of
its weight and sharp edges. Thus, we decided to use the Mattel
View-Master VR viewer for the actual VR application.
Story and Characters
The application tells the story of a little penguin girl (Fig-
ure 1c) who visits a doctor with her mother for an MRI exam
because she has stomach pains. The story is told by a vir-
tual doctor (Figure 1b), who is also a penguin. The doctor
guides the user through the story, gives background informa-
tion and feedback, explains the games and controls of the ap-
plication, and performs the simulated MRI exam. All narrative
and informational elements are presented in spoken, easy lan-
guage. At the end of the story, the cause for the patient’s pain
(a swallowed fishbone) is identified with the MR images and
the little penguin is fit again.
Interactive Objects and the Virtual MRI Environment
In order to give the young patients an impression of the MRI
environment and the devices they will encounter, we modeled
a virtual preparation room and a scanner room including a
realistic animated MRI unit with sounds recorded from a real
MRI scanner. The user can explore several interactive objects
in the two rooms (e.g. a head-coil, the MRI computer terminal
with MR images, or the emergency button). If she selects one
of these object, the virtual doctors gives explanations about
the object. The rooms are connected by a door, which is
closed at the beginning of the session. The user starts in the
preparation room and can proceed to the scanner room after
having succeeded in the first game. Afterwards, the user can
change the two rooms as often as she likes.
Games
Playful elements and games are used to induce a positive mood
and to increase motivation. Games deliver a feeling of success,
self-determination, and can facilitate knowledge transfer and
learning. The games in our application are contextually em-
bedded in the story and the process of the MRI exam. It is not
possible to lose in these games, as mistakes are not punished.
Instead, the virtual doctor gives detailed feedback about what
the player did wrong.
Information Phase: Magnet Game
Just like in the real world, the player has to take of all magnetic
objects before entering the MRI room. In this game, a variety
of magnetic and non-magnetic objects are presented to the
player (Figure 1a). The virtual doctor explains the player that
the MRI consists of big magnets, which attract any magnetic
object. Thus, the player has to identify those objects which
are not allowed in the MRI scanner. If the player selects a
correct object, it is attracted by a virtual magnet and the doctor
gives positive feedback (“Very good! This would have made a
mess!”). If the player chooses a non-magnetic object, a short
animation of the object is played as well as verbal feedback
of the doctor (“Not exactly. You can bring this to an MRI
exam!”). After all magnetic objects have been found, the
virtual doctor praises the player and tells her that she can now
proceed to the scanner room.
Observation and Modeling Phase: Control Game
In the MRI scanner room, the user is first confronted with the
virtual MRI (Figure 1b). According to the core assumptions
of VRET and play-therapy, a gradual exposure to an anxiety
inducing stimulus (the MRI scanner) supports the elimination
of fears associated with the stimulus. Hence, we design a game
allowing the child to get to know the scanner from the outside
first and to gain an understanding about the specific steps of
the scanning procedure. Like in play-therapeutic approaches,
the child is invited to re-enact these steps. At the beginning of
the game, the virtual patient lies down on the table (Figure 1c).
With the buttons of a control panel on the virtual MRI scanner
(Figure 1d), the MRI table can be moved up and down as well
as slit into and out of the tube. Another two buttons start and
end the scanning procedure. Realistic sounds recorded from
an actual MRI unity are played according to the corresponding
steps in the procedure. Thus, the child can listen to these
sounds from outside the scanner prior to her own virtual MRI
scanning experience. The player has to hit the buttons in the
right order. A wrong button is highlighted in red color and
a verbal feedback is given. If the player does not remember
the right sequence, she can select the virtual doctor who will
repeat a shorter version of the initial explanation. When all
steps are repeated correctly, the doctor explains that the scan
was successful and praises the virtual patient for her patience
and bravery and the user for her help. The virtual patient states
that the examination was not as bad as she had thought and that
she had no fear. Finally, the images of the scan are presented
and explained to the player.
Exposure Phase: Target Game
The final step is the experience of a virtual MRI scan. Before
the MRI exam starts, the user is asked to remove the HMD
and lay down. Afterwards, the child can put on the HMD
again and finds herself lying on the simulated MRI table in
the scanner room (Figure 1e). She is than slowly transported
into the tube. The virtual doctor explains that the virtual scan
starts now and that the player can exit the simulation at any
time by either clicking the virtual emergency button or just
putting down the HMD. Furthermore, the doctor reminds the
player, that the scan is accompanied by loud noises but will not
be harmful. He encourages the player to think of something
positive. For this game, as for the actual scan, it is necessary to
be completely motionless. Therefore, a target is displayed at
the tube’s ceiling. The player has to keep her view fixed on the
target, otherwise the doctor tells her not to move in order not
to blur the images. A comparable application was developed
in a non-scientific student’s project in 2015
1
. Following Bharti
et al. [4], the duration of this exercise is five minutes. Half
way through the virtual scan, the doctor praises the player,
shortly before this session ends, telling her that she almost did
it. When the child successfully finishes this game, she is told
that she is well prepared for the real MRI scan.
VR-Hardware and Interaction Design
The View-Master is an inexpensive smartphone mount com-
parable to Google Cardboard, but is made of plastic and thus
easy to clean, which is important due to the medical context.
As a child product, it is very robust and has an extra safety
mechanism to protect the smartphone. The mount comes with-
out head-straps, thus the user has to hold it in front of her face.
In the present use case, this has the advantage that the HMD
can easily be removed if the user feels uncomfortable (e.g.
because of simulator sickness or due to the individual health
conditions) or if the anxiety level becomes critical during the
exposure. The View-Master has a simple lever on the right
side of the device, which can be used for simple interaction
in the VR. Hence, we dismissed the use of an extra game
controller and decided to incorporate a simple point and click
interaction design, as this interaction concept is, according to
our aforementioned pretest, the most suitable. For this inter-
action concept, a white dot is displayed in the center of the
viewing field, which is comparable to a mouse cursor. If the
user focuses an interactive object, that is, it is centered in her
view, the dot expands to a bigger white circle to indicate that
an action is possible. To perform this action, the user has to
pull down and release the lever on the HMD. This is beneficial
for several reasons: The children do not need to remember
complex controls and do not need to find the right buttons on
the game controller while not being able to see them. Further,
no extra input device is needed, which makes the whole VR-
system less costly and easier to use in the targeted context of
medical examinations. Hence, it allows children to understand
and execute the necessary steps to navigate through the virtual
world. We arranged all objects around the user to avoid that
the user gets lost in the virtual world. Reducing player locomo-
tion to a minimum is furthermore advisable because it reduces
the risk of causing simulator sickness. However, to give the
children an exact overview of the preparation room and the
MRI room it is necessary to allow the user to travel from one
room to the other. Thus, we decided to use slow autonomous
locomotion over teleporting the user from one point in the
virtual world to another. Travelpoints as well as the starting
positions of the games are indicated by colored balloons (Fig-
ure 1b). The user has to click on a balloon in order to move to
its position or to start the respective game. Since we followed
1https://sites.google.com/site/mrisimulator/
, last visited on
2017-04-18
a child-centered design process, we conducted a focus group
testing with children with and without MRI experience as well
as with medical staff members as a proof of concept and to
ensure the target group’s acceptance of our approach (Study
1). Moreover, the testing was used to detect and correct flaws
in the application. A revised version of the prototype was then
used in a second study in the real clinical setting with children
who needed to have an MRI exam (Study 2). This study was
carried out to investigate whether the use of our application
prior to the MRI exam reduces anxiety and stress related to
the procedure.
STUDY 1
Subsequent to the implementation of a first version of the
application, we conducted a focus group testing with five
children who underwent one or more MRI scans before and
two children who have never been in an MRI scanner before.
In addition, we asked four staff members of the radiology
department of the Essen University Hospital, Germany for
their professional feedback. The participants and the chil-
dren’s caregivers were completely informed about the study’s
background and goals and gave written consent about their
participation in the study. Each participant had the chance to
try out the entire application. Afterwards, they were asked if
they would answer some questions about their opinion about
the application. We used structured interviews in order to
gain an understanding of how these three user groups perceive
usability, design, and content of our application. The interview
included questions about usability issues (“How hard was it
for you to navigate in the virtual world?”) and user experience
(“How did you like wearing the VR glasses?”, “Did you feel
comfortable while playing?”). While experienced children
could give feedback about how close the VR application is to
their experience in reality, those children without any previous
experience could describe whether they believe the application
is helpful and the information provided is easy understandable
(“Do you think, the application helps other children not to be
frightened of the MRI?”). The staff members helped us to
ensure the correctness and completeness of the content.
Results
Overall, we received positive feedback from all participants,
the children as well as the staff members, about the VR appli-
cation and the ideas behind it. The children were fascinated
by the VR system and curious in exploring the virtual world.
They enjoyed the story and its protagonists. Furthermore, they
believed that the application would be helpful to reduce fear
during MRI scans. The participants had no problems to ori-
entate and navigate in the virtual world. The pacing of the
spoken story and knowledge elements was deemed appropri-
ate. Besides these encouraging results, we identified some
issues and shortcomings in our design based on the partici-
pants’ feedback and our observations. (1) We had to reduce
the length of the spoken description of the action sequence
in the simulation game, since it exceeded the attention span
of some children. (2) The children did not recognize the bal-
loons in the scene as interactive elements. Thus, we added
a spoken description and added some balloons in the tuto-
rial, so that the children could practice the interaction concept.
Figure 2. Two participants of study 2 testing the application. Left image:
Girl with a peripheral venous catheter inserted into the back of her hand.
She was not able to hold the HMD with both hands and to pull the lever.
(3) On the basis of the medical professionals’ feedback, we
changed some details in the story to make it more accurate and
realistic. The most significant change was the introduction of
the mother as a representative for a close relative who is usu-
ally present during MRI scans of children. (4) In the majority
of MRI exams, head or body coils are used. These coils are ad-
ditional antennas, which detecting the radio frequency signals
emitted by the body during the scan. A coil looks like a frame
or, in the case of head coils, like a helmet, which fits over the
examined body part. Because these coils are commonly used
in MRI exams but have a threatening effect on many children,
the professionals suggested adding them as interactive objects.
Additionally, a body coil is placed on the virtual patient when
she is prepared for the examination (Figure 1c).
STUDY 2
We conducted a second study to test the revised prototype in
the real clinical setting with children who needed to have an
MRI exam. The aim of this study was to investigate whether
the use of the VR application prior to the MRI exam reduces
the children’s perceived stress and anxiety. Furthermore, we
wanted to get more insight about whether the target group
likes the application. Figure 2 shows two participants testing
the VR application during this study.
Method
Participants
Thirteen children aged 8 to 15 years (
M=11.84,SD =2.41
)
participated in the study (4 female, 9 male). Patients fitting
the target group were selected from the hospital’s central pa-
tient database. Additionally, a consulting pediatrician judged
whether the participation in the study was reasonable and safe
for each child based on the individual health conditions. Only
in this case the patients and the caregivers were asked whether
they want to participate in the study. Nine patients had a
history in MRI exams.
Procedure
All participants and caregivers were completely informed
about the study’s goals and procedure and gave written in-
formed consent. We received full support of the ethical board
of the University of Duisburg-Essen as well as the ethical
board of the Essen University Hospital. Patients who were
similar concerning age, sex, and previous MRI experience
were paired and assigned to either the experimental group
(EG;
N=6
) or a control group (CG;
N=7
). Participants in
Group Factor
Before
MRI Scan
After
Application
During
MRI Scan
EG 29.0 (3.95) 27.7 (6.08) 29.8 (7.47)
CG 27.7 (4.07) – 27.4 (4.61)
Prior exp. 27.6 (4.06) 27.7 (6.08) 28.4 (6.50)
No prior exp. 30.0 (3.37) – 28.8 (5.38)
Table 1. Mean STAIC-S scores for all points of measurement grouped by
condition and prior MRI experience (Standard deviation in brackets).
the EG used the VR application while they were waiting for
the MRI exam. The CG did not receive a special treatment,
that is they waited in the waiting room with their parents. All
data was assessed using paper-pencil questionnaires. We as-
sessed the current level of anxiety using the State-Trait Anxiety
Inventory for Children (STAIC) developed by Spiegelberger
[33]. The STAIC is a shortened version of the original STAI
questionnaire, adapted in language and extent for children.
Participants rated their state anxiety before, after, and during
the MRI exam on the STAIC-S subscale. Anxiety during the
MRI scan was assessed directly after the exam. In the EG
group state anxiety was additionally measured directly after
they used the VR application. Furthermore, general anxious-
ness in terms of a trait characteristic was measured using the
T-scale of STAIC. Moreover, children in the EG were asked
to rate the application according to several aspects of user
experience: fun, story, whether they liked VR and the HMD,
problems in orientation, presence and immersion as well as
whether they found it helpful and if they would recommend
the application to other children.
Results
State Anxiety
The mean STAIC-T scores indicate that general anxiousness in
this sample was within the norm [33]. Differences in the mean
scores of EG (
M=29.5,SD =6.80
) and CG (
M=33.4,SD =
5.13) were non-significant, t(11) = 1.19,p=.260.
Total STAIC-S values in this sample are rather low in gen-
eral (Table 1). The mean STAI-S score in the EG before
the MRI scan is 29.0 (
SD =3.95
), while the mean score
in the CG was 27.7 (
SD =4.07
). The EG’s mean STAI-S
score measured after the usage of the VR application did
slightly decrease to 27.7 (
SD =6.08
). During the MRI
scan, an increase of participant’s mean anxiety level in the
EG to 29.8 (
SD =7.47
) was measured. Participants in the
CG experienced a mean anxiety level of 27.4 (
SD =4.61
)
during the exam. (Figure 3). Differences in the mean
STAIC-S
scores of all three measure points in the EG group
were not significant, as indicated by a multivariate analy-
sis of variance (MANOVA),
F(1,5) = 0.41,p=.675,η2
p=
.076
. A paired-samples t-test indicated that the STAIC-S
scores of the CG did not differ significantly between both
points of measurement,
t(12) = 0.24,p=.815,d=−0.07
.
A MANOVA did not show significant differences of the mean
STAIC-S scores of both groups before and after the MRI
scan,
F(1,11) = 0.12,p=.733,η2
p=.011
. Using prior MRI
experience as a group factor, mean STAIC-S score before
Figure 3. Total state anxiety scores of the EG (shaded boxes) compared
to the CG (white boxes) over three points of measurement.
the MRI exam was 30.0 (
SD =3.37
) for participants with-
out prior MRI experience (
N=4
) and 27.6 (
SD =4.06
) for
those with prior MRI experience (
N=9
). There were no pa-
tients without prior MRI experience in the EG, thus mean
and standard deviation are the same as mentioned above.
During the MRI scan, patients without prior MRI experi-
ence reached a mean anxiety level of 28.8 (
SD =5.38
). The
mean value for patients with prior MRI experiences was 28.4
(
SD =6.50
). A MANOVA did not show significant differences
either,
F(1,11) = 0.39,p=.544,η2
p=.034
. Furthermore, we
did not find significant correlations of the STAIC-S scores with
presence, immersion, or age.
User Experience
The six children in the EG were asked to rate several as-
pects of user experience on a 3-point scale (1 = “little”,
2 = “medium”, 3 = “much”) (Figure 4). Four children an-
swered to the question whether they had fun while using the
application with “much”, one child answered “medium”, and
one child answered “little” (
M=2.50,SD =0.84
). Three
children liked the story “much”, while the other three chil-
dren answered “medium” (
M=2.50., SD =0.55
). All six
participants liked VR in general “much” and five children
liked the HMD itself “much”. One child liked the HMD with
“medium” (
M=2.83,SD =0.41
). The children had no prob-
lems orientating in the virtual world, only one child answered
that she had many problems (
M=1.34,SD =0.82
). Rather
low ratings were reached for spatial presence. The children
were asked how much they had the feeling that the virtual
world was surrounding them. One child answered “much”,
three children responded “medium”. Two children perceived
only “little” spatial presence (
M=1.83,SD =0.75
). Cog-
nitive immersion was operationalized with the question of
how much the child was aware of the real world when using
the VR application (i.e. high values indicate low levels of
cognitive immersion). Two children answered “much”, three
children answered “medium”. Only one child reported that she
was not aware of the real world (
M=2.17,SD =0.75
). The
last question to evaluate user experience was how likely the
participants would use the application again. Three children
answered “very”, while the other three answered “medium”
(
M=2.50,SD =0.55
). When asked what they did not like
about the application, two of the six children named the sounds
played during the virtual MRI scan. All children felt that the
Figure 4. Aspects of user experience were assessed with single questions,
which were answered on a 3-point scale.
application can reduce fear of the MRI exam and would rec-
ommend it to other children.
DISCUSSION
The purpose of the second study was to evaluate the feasibility
of our approach to use a playful VR application to reduce
stress and fear of children related to the MRI exam. We in-
tended to gain knowledge about how the application is adopted
and perceived by the target group, how it could be integrated
into the hospital’s routines, and whether the application is able
to positively affect the emotional state of the children. The
descriptive comparison of the mean STAIC-S scores indicates
a decline in the anxiety level of the EG directly after using the
VR application. During the MRI exam, however, it returns to
its initial level again. Although the results were not significant,
we found tendencies in the data which underline our assump-
tions. The anxiety level in the control group remains constant
before and during the MRI exam. Even though the anxiety
reduction was not persistent over the course of the MRI exam,
the observed drop in the anxiety level in the experimental
group is a promising result. Note that the application was used
only once directly before the MRI exam. We assume that in-
tense and repeated usage of the application, would strengthen
the effect and eliminate or lastingly reduce anxiety and stress
of the young patients. The small number of participants did
not raise hope for significant results. Due to the uncontrol-
lable situational circumstances in the hospital’s daily routine,
the distribution of participants over the two groups is uneven
with regard to individual variables like gender, age, and prior
MRI experience. In a field study like this, it is not possible
to rule out every influencing external factor. The influence
of behavior, worries, and fears of the parents on the child’s
own emotional experience is not to be underestimated [28].
However, it was our aim to evaluate the application before
conducting a large-scale clinical trial, which investigates the
application’s effects on children.
The results of the user experience evaluation of our prototype
are promising. All children enjoyed the application and were
fascinated by the VR. The VR-system was able to distract the
patients from the real world, even though sensory immersion
was limited due to restrictions of the VR-hardware. The most
encouraging finding for us is that all participants were con-
vinced that the application would be helpful for other children,
since the participants were mostly “experts” in undergoing
MRI exams. Thus, we are confident that our approach to use
VR for preparing children for the MRI is a suitable alterna-
tive to conventional methods. However, the current state of
research does not provide information about possible physi-
ological or psychological long-term effects of VR reception,
neither for adults nor for children. As for now, it is up to
the researcher’s and designer’s responsibility to carefully de-
sign VR-systems and to keep investigating on their impact
on humans. In order to enhance the anxiety and stress re-
ducing effect, future implementations of our approach should
incorporate elements that teach patients coping strategies to
overcome fears before or during the MRI exam. Our proposed
application could further be aligned with post-procedural inter-
ventions, which address situations in which the child remains
frightened after the MRI scan in order to prevent fearful reac-
tions in future hospital visits or MRI exams.
CONCLUSION
An MRI exam can be a lifesaver and sedation can be a risk.
Therefore, it is important to help children to cope with this
frightening procedure. This paper shows that preparing young
patients for the MRI scan with the use of a playful VR appli-
cation is a promising approach for a medication-free method
to reduce anxiety and stress and eventually supports the young
patients’ well-being.
ACKNOWLEDGMENT
We thank A. Schroeder for her contribution to this project.
We also thank Dr. O. Basu and the staff members of the
radiology department of the Essen University Hospital for
their valuable feedback. Finally, we thank all young patients
and their parents for participating in our studies.
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