The Development of a Virtual Reality Simulation to Reduce Anxiety in Pediatric Patients Undergoing Magnetic Resonance Imaging

Summary

Here, we present a protocol to develop a virtual reality (VR) gamified simulation to reduce anxiety in pediatric patients undergoing MRI scans. By replicating the sights and sounds of the MRI environment, the VR experience will help children become familiar with the procedure, aiming to improve comfort and cooperation.

Abstract

Magnetic Resonance Imaging (MRI) is a valuable diagnostic tool in pediatric care, offering high-resolution images without ionizing radiation; however, the unfamiliar environment, confined space, and loud noises may cause distress, claustrophobia, and anxiety. This may lead to an increased need for sedation, and longer imaging times. At Victoria Children's Hospital in London, Ontario, the Child Life program currently uses a doll and MRI model to help reduce anxiety in pediatric patients through a learning-based approach. While these methods are effective, they are limited in their ability to provide a realistic representation of the MRI experience. To address this, we developed a gamified MRI experience designed specifically for pediatric patients at Victoria Children's Hospital using virtual reality (VR), a computer-generated 3D environment experienced through a headset. The simulation replicates the sights, sounds, and spatial aspects of the MRI environment, helping children to familiarize themselves with the experience beforehand. While our VR room is a replica of the real MRI room in Victoria Children's Hospital, it could be adapted for use in other facilities by modifying the environmental details. Future work will evaluate the simulation's effectiveness in reducing anxiety through quantitative and qualitative assessments.

Introduction

Magnetic resonance imaging (MRI) is a non-invasive technique used to produce three-dimensional images of soft tissues to aid in disease diagnosis and treatment monitoring¹. MRI is considered to be one of the safest imaging modalities for children because it does not involve ionizing radiation¹; however, the procedure can be particularly challenging for young patients. Children must lie still in a confined tunnel for up to an hour while exposed to loud noises², an experience that may cause fear, anxiety, claustrophobia, or a heightened dread of the diagnosis itself^1,2,3,4,5. Such anxiety may result in physical restlessness (children ages 5-10 are particularly prone to movement⁶), poor compliance, or behavioural difficulties⁷. The MRI procedure is highly dependent on the cooperation of the patient, as slight movements on the scale of millimeters can distort images, causing the need for repeat scans. This can be distressing for families and financially burdensome for hospitals⁸. Parental or caregiver anxiety can contribute to a child's stress during an MRI, as children often mirror adult emotions⁹; therefore, the involvement and compliance of parental figures during the procedure has been shown to contribute to the success of a child's MRI scan¹⁰.

Several techniques are used to manage pediatric anxiety before an MRI, but their effectiveness is limited. Sedatives or anesthetics help to keep children still during the scan, yet they have been associated with a higher incidence of adverse events, including impaired coordination, dizziness, and heightened agitation^8,11. As an alternative, psychological preparation has been shown to reduce pediatric stress in medical settings^12,13,14 and lower the need for sedation and anaesthesia before an MRI^10,15. Psychological preparation includes the use of interactive videos on a tablet^16,17, educational and distraction techniques^6,7, play therapy⁷, cognitive behavioural therapy training¹⁸, and physical mock MRIs^19,20. This approach, however, has limitations, as evidenced at Victoria Children's Hospital in London, Ontario, Canada. Child Life Specialists in the Child Life Program use various psychological preparation tools to address anxiety or fear in pediatric patients prior to an MRI; depending on the child's age, anxiety level, and personality, interventions may include a picture book, an iPad video, a toy replica model, a large-scale MRI replica, or a pre-scan tour (Figure 1). During the scan, children can also bring a comfort toy or blanket into the MRI or watch videos on a screen. These approaches aim to educate the child about the MRI process while providing distraction, comfort, and familiarization; however, these interventions have drawbacks: tours are often unavailable because the room is in use; picture books, replica models, and iPad videos may not engage older children or provide a full picture of the MRI experience; none of these methods replicate the loud noises of the MRI; and, perhaps, most importantly, they don't allow children to practice staying still in an enclosed space. Novel interventions, therefore, that are engaging and immersive are needed to address these limitations.

Virtual Reality (VR) is a three-dimensional (3D) computer-generated environment viewed through a head-mounted display that has been increasingly used in education, training, and healthcare. VR creates an interactive and realistic simulation of the real world²¹, one to which children are especially responsive, as this technology creates the sense of a physical presence in the virtual world^22,23. Studies have indicated that VR effectively reduces pediatric pre-hospital anxiety: a meta-analysis by Eijlers et al. found that VR interventions significantly reduce pain and anxiety in children undergoing medical procedures, especially when used as a distraction tool²⁴; similarly, Chiu et al. demonstrated that immersive VR could effectively reduce preoperative anxiety in children through familiarization by offering a virtual hospital tour²⁵. These benefits extend to pediatric MRI preparation, for which VR has the potential to reduce the need for sedation; several studies have explored VR as a pre-MRI intervention tool with positive results. Ashmore et al., for example, developed a free VR app that uses a 360° video to guide children through the MRI, a technique that was highly rated by both staff and patients for ease of use and helpfulness while preventing the use of general anaesthesia in four of five patients²⁶. A randomized controlled trial by Saliba et al. found that exposure to even 5 min of a VR MRI experience significantly reduced anxiety in pediatric patients²⁷. Moreover, a custom VR MRI app with a standard manual and a hospital Child Life Program created by Stunden et al. found that the VR group reported higher caregiver satisfaction and significantly lower caregiver anxiety. This was an important finding, as parental caregiver distress is expected to influence child responses during medical procedures²⁸. Building on these findings, more recent studies have evaluated the impact of interactivity and gamification in VR MRI preparation tools. A study by Yang et al. introduced a standalone head-mounted display (HMD)-based VR MRI simulator with multiple modules, including a hold-still game, a 360° video, and a mindfulness section. Their pilot study showed significantly higher engagement, satisfaction, and perceived effectiveness compared to standard educational materials²⁹. Another study conducted by Yang et al. compared four modalities: 2D video, 360° video, passive VR, and gamified interactive VR, with the gamified VR condition significantly reducing head motion and improving self-reported preparedness and engagement among adolescents. The findings of this study supported the hypothesis that behavioural rehearsal and immediate feedback may improve procedural readiness and reduce scan failures due to motion³⁰. Liszio and Masuch similarly demonstrated that a playful, child-centered VR application that incorporated desensitization and interactive storytelling can reduce MRI-related anxiety. The design emphasized the role of gamification and gradual exposure to stress-inducing stimuli, which aligns with modern pediatric frameworks³¹. Despite these successful results, however, the technology has not been fully implemented.

A VR simulation of the MRI experience at Victoria Children's Hospital was developed to address the limitations of existing pediatric MRI-preparation tools. The design of each component was informed by consultations with Child Life Specialists, MRI technicians, and direct observations of the hospital's MRI scanning procedure. The hospital environment was initially recreated using 3D modeling to form a detailed virtual environment. The 3D model was then integrated into a game engine to create an immersive VR experience. Several tools were used in the development process, including: the "level", which represents the physical MRI room built using 3D modeling of the hospital environment; the "level sequencer," which is a timeline-based animation tool used to animate objects and synchronize motion; the animated "cine-camera actor" that simulates the user's point of view to create the sense of sliding into the virtual bore; an audio track replicating the MRI machine's noise, which is synchronized with the sliding animation to mimic the auditory experience of an MRI; a screen simulation to replicate the MRI-safe distraction screen attached to the bed, which MRI technicians can upload as a video for children to watch during the scan to help children remain still; the VR pawn, which acts as users' entity in the virtual environment, as it includes head and hand tracking; and the "grabbable object," a handheld, interactive cube that is used to begin the MRI simulation sequence and, when picked up, triggers the start of the animation timeline. To support the involvement of caregivers and Child Life Specialists, a multiplayer system was integrated to enable multiple users (e.g., the technician, parent, caregiver, or Child Life Specialist) to interact in the same virtual environment through a client-server model using voice chat through microphones to support real-time communication between players, mitigating children's feelings of isolation.

The purpose of this study was to develop a gamified virtual simulation of the MRI experience at Victoria Children's Hospital in London, Ontario, for use by the Child Life Program as an anxiety intervention for pre-MRI pediatric patients. The simulation, viewed through a virtual reality (VR) head-mounted display, aims to familiarize children with the MRI scanner and surrounding environment, reducing anxiety by providing an accurate and immersive representation of the real-life experience. The multiplayer mode allows younger patients to engage with the simulation, promoting ease of use across a wide range of age groups. Although the VR simulation developed in this study was specifically modeled after Victoria Hospital, the methods are adaptable and can be applied to recreate any healthcare setting where environmental familiarization may help ease patient anxiety. This is the first known study to report a virtual MRI experience that incorporates the additional interactive features of multiplayer functionality, a handheld tool to exit the experience, a video screen inside the MRI, and a voice chat mode. With this research, we hope to develop a tool that will be used in the future by Child Life Specialists at Victoria Children's Hospital to enhance the lives of pediatric patients.

Protocol

Ethical approval for this study was obtained from the Western University Health Sciences Research Ethics Board (HSREB) (Project ID: 116749). Written informed consent was obtained from the human participants. The reagents and the equipment needed are listed in the Table of Materials.

1. 3D modeling of assets

NOTE: Create a realistic, to-scale 3D model of the MRI machine and its surrounding environment using 3D modeling software.

1. Photographic documentation
   1. Capture photographic documentation of the real MRI room from multiple angles. Ensure all walls, equipment, furniture, and architectural features are visible to provide accurate reference material.
2. 3D shape modeling
   1. Launch the 3D modeling software.
   2. Import the reference images into the workspace.
   3. Create the shapes that make up the foundation of the MRI room using geometric primitives, such as cubes, cylinders, and planes.
   4. Adjust the dimensions of the floor, ceiling, walls, and cabinetry to match real-world proportions based on the reference images.
   5. Construct the MRI machine and video screen by layering and modifying cylinders, spheres, and curved surfaces to replicate the scanner bore and exterior architecture.
   6. Apply subdivision and bevel modifiers to smooth edges and create realistic contours.
   7. Use vertex mode to refine curved elements and add structural details to the model.
3. Spatial calibration
   1. Use a camera matching tool to overlay a three-dimensional axis on the reference images.
   2. Align the virtual camera perspective with the original photographs to ensure spatial accuracy and proportionality.
   3. Position and scale all 3D objects based on calibrated camera views, confirming their alignment with reference images to ensure correct depth, rotation, and placement.
4. Texturing
   1. Apply materials and textures to each surface of the model. Select colours that match the real MRI room environment.
   2. Wrap texture images over objects where necessary using UV editing tools.
   3. Adjust surface properties, including roughness, reflectivity, and metallic characteristics, to simulate realistic lighting interactions.
5. Collaborative development
   1. Configure a private network to support real-time multi-user editing within the modeling software.
   2. Enable simultaneous collaboration by allowing multiple contributors to build and place assets together in the same file.
      NOTE: The completed 3D model should closely resemble the real room both spatially and visually, accurately capturing its dimensions, layout, and key components (Figure 2 and Figure 3). Once the model is complete, it can be imported into a game engine to add the functional elements required for use with VR.

2. Functional simulation development

1. Level creation
   1. Create a basic level in the game engine or import a pre-built 3D model³².
   2. Import the previously modeled 3D virtual assets into the new level to match the real-world scene (Figure 4).
   3. Place lighting elements such as directional light and point light.
   4. Once the scene has been built, configure the world settings.
      1. Set the game mode to the default VR game mode to ensure that when the player enters the game, the VR mode will be automatically enabled.
      2. Set the default pawn class to VR pawn to ensure the VR pawn will be generated at the PlayerStart position.
2. Level sequencer
   1. Create a level sequencer by navigating to Cinematics, then select Add Level Sequence in the main viewport of the level in Unreal Engine. Rename and save the sequence{Engine, #4}.
   2. Once the sequencer window has opened automatically, import the required actors from the outlier (e.g., lights, static meshes) and either drag the actors to the sequencer timeline or load them in by clicking on Track, then Actor³³.
   3. Edit the transformations in the sequence, such as location, rotation, and scale.
3. Audio integration
   1. Record the MRI sound from a 3T scanner with a patient on the table from the MRI acquisition console microphone. Record the MP range, diffusion, and EPI sequences.
      NOTE: No quiet parameter was activated on the recorded MRI scanner. Pre-recorded MRI sounds reached a maximum of 75db when played through the VR headset.
   2. Add a .wav audio track of the MRI sound. Click on track, then audio track in the sequencer window to find the MRI audio.
   3. Select and position the MRI audio file on the timeline.
   4. Synchronize the audio with animation playback so it will start when the user lies down and slides into the MRI machine.
4. Camera animation
   1. Add a cine camera actor by navigating to track, actor to sequencer, and cine camera actor in the sequencer window.
   2. Select the cine camera actor, then track and transform in the sequencer.
   3. Add a keyframe at the start of the timeline. Move to the end, adjust the camera's transform, and add a second keyframe to animate camera movement.
   4. Add the cine camera actor, virtual legs, MRI sound, video display, and screen to the lever sequencer track and place the keyframe. Synchronize all meshes in the animation so the whole body moves with the cine camera (Supplementary Figure 1).
   5. Preview the animation using the play button in the sequencer (Figure 5).
5. Screen simulation
   1. Begin by importing an MP4 video file of any video that could be used in the MRI.
   2. Use the media player to load the video and generate a material.
   3. Apply the material to a default static mesh (e.g., a flattened cube) to act as a screen.
   4. Apply the previously modeled 3D exterior of the default static mesh that is inserted where the lobby will be.
   5. Play the video using the Media Player trigger node to display distraction content on the screen (Figure 6 and Figure 7).
6. Grabbable object and animation trigger
   1. Add the grab component to a default cube to enable human-computer interaction³⁴ (Figure 8).
   2. Implement hand interaction using the motion controller grip button by creating a sphere trace around the grip location.
      1. Attach the actor to the controller upon grip input.
      2. Detach the actor upon release of the controller grip button.
   3. Configure the grab component to trigger animations, such as beginning the MRI scan.
   4. Use blueprint logic to open the gate restriction after the object is grabbed. When the object is not grabbed, close the input channel to prevent accidental touches (Supplementary Figure 2).
   5. Trigger the animation by pressing the trigger key of the right controller. Call the play animation function in the VR pawn.
   6. Ensure the blueprint can find the corresponding sequence player at the current level and the matching level sequence actor (Supplementary Figure 3).
7. Creation of a widget-based interface
   1. Create a new user widget blueprint.
   2. Add virtual buttons as part of a dropdown list labeled: Reset orientation, Restart, Create a session, and Join a session (Figure 9).
   3. Bind the "Create a session" to logic that starts the server and loads the correct level (Supplementary Figure 4).
      NOTE: Use widget buttons instead of controller input due to the limited number of input options on VR controllers. The reset orientation button will re-center the user's view if tracking becomes misaligned; restart will transport the VR pawn back to "PlayerStart"; create a session will create a new multiplayer session and server; find server will search for available sessions to join.
8. Create a multiplayer simulation³⁵
   1. Modify the configuration file to enable online functionality.
      1. Install and integrate the Advanced Session plugin.
      2. Enable the following plugins for voice chat and multiplayer mode: Online Subsystem Utils, Advanced Steam Sessions, and Advanced Sessions.
      3. Add button transformers to connect Meta Quest controller input with Unreal Engine events by opening the Project Settings and navigating to the Input section. Set the action mapping for RightTrigger to Oculus Touch (R) Trigger, LeftTrigger to Oculus Touch (L) Trigger, and LeftXForQuit to Oculus Touch (L) X Press. Use these mappings to trigger voice chat and enable menu interactions through the VR controllers.
   2. Use the Create a session button in the widget-based interface to start a session and let the server join the correct level.
      1. Use a dropdown list to display server names retrieved from session search results.
      2. Retrieve available server names from the session search results using a session-finding function.
      3. Pass each server name to a widget item and add it to the dropdown list.
      4. Allow users to select a session from the list and join the corresponding server.
   3. Define default roles such as Server (technician or parent) and Patient or Client (child or additional users).
      1. Place PlayerStart actors in the level and label each with a display name based on assigned roles to differentiate users in multiplayer mode: Player1: Technician or Caregiver; Player2: Patient or Client (Supplementary Figure 5).
      2. Use Blueprint logic to assign PlayerStart tags using a player counter.
      3. If more players are needed, create another PlayerStart in the level and change the name tag to represent the Client or Patient number.
   4. Implement head and hand synchronization for better user interaction.
      1. Add tracking components for the headset and hand controllers to the VR pawn.
      2. In the Event Tick, collect local transform data from the headset and hand controllers.
      3. If the controller belongs to the local player, send transform data to the server using a remote procedure call. If the controller belongs to a remote player, receive the transform data from the server and apply it to the mesh or camera actor (Figure 10).
   5. Use a client-server model (CS mode) to synchronize actions across users and pass all information to the server (Supplementary Figure 6).
      NOTE: Information should be passed to the server so subsequent operations are distributed to each port, allowing synchronization to be performed. When using multiplayer mode, the widget must be changed from "on clicked" to "on pressed" (Supplementary Figure 7).
9. Voice chat integration³⁶
   1. Open the VR Pawn blueprint.
   2. Add a voice capture component to the VR Pawn to enable the voice recording function.
   3. Set the component to activate upon entering a multiplayer session.
   4. Configure the voice system to link with the session state and activate only when connected to a server
   5. Configure the VoiceThread component to activate voice chat. Test voice chat by launching two PlayerStarts and confirming bidirectional audio transmission during a multiplayer session.
10. Exit and reset functions
    1. Create an exit animation and load it into the level.
    2. Use blueprint logic to stop the current animation before triggering the exit animation (Supplementary Figure 8).
    3. Add a reset function that teleports users back to the starting position if misaligned (Supplementary Figure 9 and Supplementary Figure 10).
11. Pre-testing with healthy volunteers
    1. Test the simulation on 5 healthy graduate student volunteers who have previously experienced an MRI scan as a pre-test.
    2. Use a 5-point Likert scale survey to allow healthy volunteers to rate the similarity of the VR MRI to their previous experience with a true MRI. Use 8 questions that reflect the physical appearance of the MRI machine and room, the noise, visuals during the scanning process, sense of being confined or enclosed, feeling of lying still, and the overall impression of the environment.

Results

A functional, immersive, and realistic VR MRI simulation was successfully developed to help pediatric patients at Victoria Children's Hospital prepare for MRI procedures. The simulation's supplemental features operate reliably, demonstrating its readiness for clinical testing. The first successful outcome was the accurate recreation of the MRI scanner and surrounding environment using 3D modeling techniques. Since reference photographs were used to calibrate virtual assets to match real-world spatial dimensions, the fina...

Discussion

The development of the virtual MRI simulation was shaped by design decisions that influenced its usability in a pediatric setting. Input from Child Life Specialists and MRI technicians played an important role in replicating real-world procedures virtually. For example, the inclusion of a video MRI display above the bed, which is commonly used in actual scans as a distraction tool, was implemented into the virtual MRI based on the recommendations made by Child Life Specialists. Similarly, the addition of a "leave sim...

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Advanced Sessions Plugin	Community Plugin	https://vreue4.com/generated-node-documentation?section=advanced-sessions-plugin	Enables Steam multiplayer features in Unreal Engine
Blender Software	Blender Foundation	https://www.blender.org/	Used to model 3D virtual MRI environment and assets
Fspy	Fspy Project (GitHub)	https://fspy.io/	Used for camera matching and perspective calibration
Hamachi	LogMeIn	https://vpn.net/	Used to create a virtual LAN for multiplayer sessions during development
Meta Quest 3 and 3S Headsets	Meta	https://www.meta.com/ca/quest/?srsltid=AfmBOooSwFweWKye9LY HHsSsuGhZgdZZxi-m7xAFtC ecIK2ekZnTAhGr	VR headsets used for testing and deploying the simulation
Multi User Plugin	Unreal Engine Marketplace	https://dev.epicgames.com/documentation/en-us/unreal-engine/multi-user-editing-in-unreal-engine	Enables collaborative editing in real-time within Unreal Engine
Steam	Valve Corporation	https://store.steampowered.com/	Online service platform required for multiplayer connection (via Steam Online Subsystem)
Unreal Engine	Epic Games	https://www.unrealengine.com/en-US	Game engine used for developing the VR simulation
Voice Chat Plugin / VOIP Talker	Unreal Engine	https://dev.epicgames.com/documentation/en-us/unreal-engine/voice-chat-with-epic-online-services	Enables voice chat in VR multiplayer environment
Windows PC	Microsoft	Self assembled	Development and testing platform for building the VR project. AMD Ryzen 9 5900X CPU, Nvidia RTX 3080Ti GPU, 32GB RAM, and a 2 TB SSD 4TB hard drive