Mixed Reality Glasses with Picture-in-Picture Navigation for Patients with Homonymous Hemianopic Visual Field Loss

Area of Science:

• Ophthalmology
• Human-Computer Interaction
• Rehabilitation Technology

Background:

• Limited visual rehabilitation options exist for homonymous hemianopia (HH).
• Mixed reality glasses (MRG) offer potential for visual navigation assistance.

Purpose of the Study:

• To develop and evaluate prototype software for MRG to aid HH patient navigation.
• To assess the utility of picture-in-picture navigation (PIPN) for HH patients.

Main Methods:

• Developed Unity-based software for HoloLens 2 MRG, enabling real-time PIPN.
• Used WebSockets for MRG-remote interface communication and Streamlit for calibration.
• Conducted a crossover study testing HH patients on an obstacle course with and without MRG.

Main Results:

• Transposed 52 degrees of visual field into the intact hemifield using PIPN.
• Patients rated MRG 19.7% more helpful for ambulation (P=0.028).
• No statistically significant difference in walk times observed between with and without MRG conditions.

Conclusions:

• A working prototype for PIPN on MRG was successfully developed.
• PIPN is a viable rehabilitation strategy for improving ambulatory navigation in HH.
• Future hardware and software advancements are expected to further enhance PIPN effectiveness.