Remapping Control in VR for Patients with AMD

Aug 2021 - Dec 2021

Age-related Macular Degeneration (AMD) is the leading cause of vision loss among individuals over 50 years old. The AMD VR project aims to improve the visual display for AMD patients by remapping the image in VR. The project includes a two-part interface with a VR-based visualization for patients and a connected doctor's web interface to optimize the VR view. As the UI/UX designer for the doctor's web interface, I focused on making the AMD assessment page more intuitive and streamlined for eye doctors, especially with regard to the drawing function and fine-tuning of the warping effects. To achieve this, I conducted extensive background research to study existing interfaces for eye doctors and collaborated with professionals at Emory to better understand their needs. Based on this research, the design of the AMD VR project is interacted with and pilot-tested with a group of ten eye care professionals.

My Contributions

UIUX design, Drawing-function programming, preliminary evaluation, usability testing preparation
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Research Question

How can a VR-based assessment system support eye doctors to treat patients with AMD to improve their quality of life?

Tools

Figma

Html

JavaScript

Unity

- Advisor: Michael Nitsche
- 3+ Collaborators
- Accepted to IEEE VR 2023

Previous
Doctor's Interface

OVERVIEW

In the previous version of the Doctors' interface, eye doctors were able to access eye charts and activate the warping effect with a single click. This would trigger a uniform, circular warping effect in the patient's VR view.

New Interface

Our team recognized the need for an updated interface design for our system. The previous design had limitations as it lacked the capability to hand-adjust the affected area, resulting in a lack of personalized adjustments for the warping effect for each participant. Additionally, the previous version did not allow doctors to adjust the conditions on each eye separately. As a result, we have embarked on a project to create a new interface that addresses these shortcomings, providing greater flexibility and precision in customization for both patients and doctors.

Assessment View
We have taken the assessment view to the next level by allowing eye doctors to make manual adjustments to the occluded area. This is made possible by importing the patient's Optical Coherence Tomography (OCT) image directly into the interface and using the pen and eraser functions to draw around the scotoma area. The customized image created is then imported into the VR application, where the warping effect is activated, resulting in a more personalized and effective treatment for patients as they experience these changes in the VR viewpoint.

Warp Control
The warp control page has been updated to provide eye doctors with the ability to activate the warping effect and color corrections, as well as adjust their intensities in real-time with patients. Additionally, a test image and model have been included to allow for effective fine-tuning of these settings.

VR Training
We have added a new function and page to our system: VR training. With this feature, eye doctors can access a diverse range of 3D models that differ in their level of detail and color contrast, enabling them to fine-tune the warping effect with greater precision. This allows doctors to provide more accurate and effective treatment to their patients. To further customize the VR experience, doctors can manipulate the location of the user and distance to the models. However, as prolonged exposure to the warping effect in VR could potentially induce motion sickness, we have incorporated an elapsed time clock into the VR training page to monitor and prevent this. This feature ensures patient comfort and safety during the training process, and helps doctors provide better care to their patients.

Patient's Interface

Doctors' tracing of the affected area is transported to the VR interface. Then, the VR prototype delivers a simulated central scotoma, which follows the movement of the eye using HTC Vive Pro’s integrated Tobii eye tracking. It also provides a linear remapping, which pushes the central image part outside the simulated scotoma to provide typical remapping. Both effects are rendered individually for each eye, allowing adjustment for different conditions.

Preliminary Eval (n = 1)

After developing the new interface, we received valuable feedback from Dr. Primo at the Emory Eye Center. During our consultation, we discussed several key areas of the interface, including the potential inclusion of a higher resolution 3D object for more accurate testing of the warping effect, the ability to adjust the affected area, and advancements in the testing process.

Good

Hand adjusting the affected area
Access to historical patient data
Providing control over the warp effect

things to consider

For test models, use models with highly contrasting colors like black and white as they tend to work well. However, red and green can pose issues for vision-impaired patients, so it may be best to avoid using them.
Too much detail on the test model can overwhelm the patient and should be used with caution
Provide patients with the ability to adjust the warp effect in real-time as well
Include patient engagement activities, such as checkerboard and domino games. These activities can be used to effectively test the warping function and help patients become more comfortable with the visual effect

User Study (n=10)

The usability study was conducted with the partially updated version of the interface. Participants first tested the doctor control interface, then they tested the VR visualization before the session closed with a concluding exit interview. A single session lasted up to 40 minutes and testing was conducted on-site at the Emory Eye Center. Data collected consisted of SUS, interviews, and video recordings of the actual interaction.

Participants

Participants were recruited from the professionals at the Emory Eye Center (n=10; 6=female/ 4=male). Overall, participants showed high levels of expertise in the field of eye care but less so in the use of VR.

Results

QUANTITATIVE

The results of the SUS questionnaires show a favorable overall response. The mean SUS value for the doctor interface was 68.89 and for the patient interface 68.25. That means, for both cases, the usability factor was above average compared to other interfaces.

Qualitative

After conducting usability tests with both the doctor’s interface and the patient interface, participants were interviewed and asked about their experiences interacting with the system.

Promising Tool
The qualitative feedback showed that both interfaces were accessible and allowed the users to engage with the tools in meaningful ways. There were differences regarding the comfort level of the participants, including the headset’s weight and the VR technology but the principal concept of remapping was seen as a promising approach. One participant highlighted that “the warping was incredible, you know, to be able to look around and see (…) the other parts of the image that you're trying to see”(P10) which was a sentiment that was echoed by others (P6).

Learning Curve
In order to bring this system to eye care practices multiple experts noted that there would have to be a learning process in place. P4 stated that “depending on who uses it and…how good they are of technical things, there will be a lot of training there”. Likewise, the doctor interface was perceived as in need of some additional assistance for its users. “Just because somebody is very smart academically doesn't mean that their visual perceptual skills are wonderful. So you need a tool to help them understand kind of what's going on.”(P2)

In Summary
The tool was perceived as helpful – at the same time, the learning curve to properly operate this VR tool was noted. One perceived strength was the value of the combined applications. One expert acknowledged the connection between the doctor and patient interface in “the fact that you have the opportunity to alter the size and just check and double check and make sure that the patient actually interfaced well, with the size of the macular, that you're drawn out. (…) That was definitely a good feature.”  (P9)

Discussion

We have demonstrated a two-part interface that utilizes the variable image corrections available in VR headsets with rich controls for doctors to effectively deploy these features and customize them. As has been shown, the VR and doctor interface have enabled us to create a tool that is useful to doctors and promises their patients with AMD a new type of care. While there is still some training that our users would need to expertly navigate both interfaces, the applications have a level of ease of access that enables a doctor to help build a unique visual experience for potential patients.