Evaluation of Virtual Reality Perimetry and Standard Automated Perimetry in Normal Children

Abstract

Purpose: The Olleyes VisuALL-K is a pediatric videogame-based static threshold perimeter using a virtual reality headset. We determined normal threshold sensitivities for the 24-2 test locations using the virtual reality perimetry (VRP) and also tested patients on the Humphrey Field Analyzer (HFA). Patient satisfaction for the two instruments was compared.

Methods: This exploratory study tested 50 normal pediatric participants aged 8 to 17 years on the HFA and VRP. The main outcome measure was threshold sensitivity at the 24-2 test locations for the two instruments.

Results: The mean participant age was 13.0 ± 2.6 years; 50% were female. The threshold values for VRP are reported as measured on the device and after conversion to an HFA-equivalent scale. Age-adjusted thresholds showed a mean sensitivity of 31.8 ± 1.1 dB (46.1 ± dB HFA equivalent) diminution from the maximum light intensity in the VRP and 31.0 ± 1.5 dB diminution from the maximum light intensity in the HFA; interparticipant variability in mean threshold sensitivity was 2.7 ± 0.4 dB for the VRP and 2.7 ± 0.6 dB for the HFA. The HFA demonstrated decreased threshold sensitivity with increasing eccentricity, whereas the VRP threshold did not seem to vary with eccentricity. Mild age effects on threshold sensitivity were seen in the VRP and the HFA (R2 = 0.11, P < 0.001 and R2 = 0.05, P < 0.05, respectively). The mean time to completion for VRP and HFA was 7.6 ± 1.5 and 5.3 ± 0.9 min/eye, respectively (P < 0.0001). Patient satisfaction scores favored VRP (P < 0.01) despite the longer test duration.

Conclusions: The Olleyes game-based VRP and HFA can be used to map out the peripheral vision in normal children. The VRP has a higher patient satisfaction when used in children than the HFA. The portability of the test allows it to be performed in a myriad of environments, lending a flexibility that can benefit this population.

Translational relevance: This virtual reality perimetry device provides an alternative to the Humphrey Field Analyzer for children.

Figure 1.

Olleyes Headset and wireless remote (A). A 9-year-old child completing the VRP in clinic (B).

Figure 2.

VisuALL screen luminance (cd/m2) vs RBG (gray scale) values.

Figure 3.

Scatterplot comparison of mean threshold sensitives in each eye on the HFA and VRP (A) and the pointwise threshold comparison in dB for corresponding points on the VRP and the HFA (B). The plots are fit with standardized major axis (SMA) regression lines (red) with 95% confidence intervals (CI). The blue dotted lines are a slope of 1. The VRP is plotted on a HFA-equivalent dB scale on the y axis to provide a comparison.

Figure 4.

Parametric regression of mean threshold sensitivity by age found small age effects with the VRP (A) and HFA (B) devices. The VRP values here are reported in HFA-equivalent threshold values, to provide a comparison.

Figure 5.

Heatmap of the distribution as represented by (A) median threshold sensitivity at each location; (B) fifth percentile threshold sensitivity; and (C) interparticipant variability of threshold sensitivity at each location. There was no significant difference in overall interparticipant variability (P > 0.25) between the devices. (D–F) A map of the same values as (A–C), but the VRP thresholds have been converted to an HFA-equivalent scale. The values of each threshold point on the VRP are higher but the same general pattern is demonstrated.

Figure 6.

Scatterplot of test duration of each participant on the VRP and the HFA (A) and mean minutes per eye broken down by age on the VRP (black) and the HFA (gray) (B). Of note, the VRP device tests both eyes simultaneously so the time is total time divided in half.

Figure 7.

Box plot of patient satisfaction scores. Scores were measured on a 1 to 5 Likert scale. Patient satisfaction scores favored the VRP device experience (P < 0.01).