Improved Vision with a Novel Enhanced Reality Non-Immersive Head-Mounted Device (HMD) for Reducing Low Luminance Dysfunction (LLD) in Patients with Age-Related Macular Degeneration (AMD)

Abstract

 

Purpose:

 

Geographic atrophy in AMD is commonly associated with LLD. The use of a novel non-immersive HMD for improving vision in dim light was investigated.

 

Methods:

 

Ten patients (from 63 to 80 years old, mean age 71) were included. They showed geographic atrophy due to AMD, 3 of them with foveal sparing. ETDRS distance visual acuity (VA) and Pelli-Robson contrast sensitivity (CS) were assessed in 10 lighting conditions, from 10 to 700 lux. All patients were tested with and without the HMD. The user can see the scene both in the translucent video display (luminance 1500 cd/m²) and through each lens. Finally, adaptation to a sudden decrease from 700 to 10 lux was evaluated.

 

Results:

 

For 6 patients, both VA and CS were improved when using the HMD. Improvement occurred in all lighting conditions for 2 patients and more selectively in dim light for 4 patients. For the remaining 4 patients, only VA was improved in dim light. The HMD improved VA in at least one lighting condition in all patients (improvement median 0.21 logMAR, range 0.04 to 0.38) and improved CS in at least one lighting condition in 6 patients (increase median 0.15 logCS, range -0.15 to 0.90). Prolonged dark adaptation time was shortened when using the HMD.

 

Conclusions:

 

The HMD allows the luminance range of the display to be kept around the same value at all lighting conditions. As a result, benefits were obtained both in stable lighting conditions and after sudden light decrease. In dim light, such a HMD compares favorably with optical aids which cannot increase the luminance of the distal scene. Further improvements resulting from additional image processing enhancements by the HMD will be explored later.

 

Keywords: low vision • age-related macular degeneration • visual acuity