Inter-test Comparability of a Novel VR Perimetry Device with the Humphrey Visual Field Analyzer

Theme: Glaucoma
What: Glaucoma
Part of: Glaucoma IV: New Tech / Glaucome IV: Nouvelles technologies
When: 6/1/2024, 11:15 AM - 12:45 PM
Where: Room | Salle 801

Abstract

Purpose

Mapping of visual fields is fundamental to ophthalmologic examination; it aids clinicians in assessing the progression of eye diseases, localizing lesions of the visual pathway, and verifying fitness to drive. At present, the Humphrey Visual Field Analyzer (HFA; Carl Zeiss Meditec Inc., California) is the accepted benchmark amongst visual field testing equipment. However, while validated as a reliable tool, the HFA is large, expensive, and necessitates a fixed testing environment. In response to the challenges, virtual reality (VR) headsets have emerged as an alternative to perimetry testing. This study investigates the inter-test comparability of a novel VR perimetry device (RetinaLogik Inc., Calgary, AB) relative to the HFA.

Study Design and Methods

This prospective, single-center study was conducted on 20 eyes of 12 patients with 70% glaucoma-suspect and 30% glaucomatous eyes. Exclusion criteria included a high false positive rate (>15%) for either device, ensuring that the results of the comparison were solely attributable to device performance rather than being strongly influenced by patient-related factors. Each participant completed visual field testing using both devices. The same grid pattern (either 24-2 or 30-2) was used for each patient on both devices, and the grid was selected based on the patient’s clinical care needs. The data extracted included global mean deviation [MD], pattern standard deviation [PSD], global mean sensitivity [MS], and pointwise sensitivity. Linear regression analysis was used to evaluate the MD and PSD data. A Bland-Altman plot was used to assess the mean difference and level of agreement between the two devices. Lastly, pointwise analyses were conducted including a heatmap presentation of the results.

Results

Linear regression analysis demonstrated a strong Pearson correlation coefficient of r = 0.8327 for MD and r = 0.9083 for PSD (both P<0.0001). Similarly, Bland-Altman analysis of the global MS also demonstrated a strong Pearson correlation coefficient of 0.8252 (P<0.001). Additionally, the Bland-Altman plot revealed a bias of 0.80 dB with 95% limits of agreement between -2.1 and 3.7, when comparing global MS of the HFA and VR device. Pointwise analysis showed a statistically significant Pearson correlation coefficient of 0.8027 (P<0.0001). Differences in light sensitivity between both devices, averaged individually at each stimuli location, were plotted on a heatmap, and demonstrated a variation between -2.21 and 4.11 with a mean difference of 1.02 dB. 

Conclusions

This study demonstrates a strong correlation between the RetinaLogik VR headset and the HFA, in a population of glaucoma-suspect and glaucomatous eyes. These promising results indicate a potential for broader and more routine use of this accessible device.

Presenter(s)

Presenting Author: Mina Mina

Additional Author(s):

Janelle Olughor, University of Calgary

Antoine Sylvestre-Bouchard, University of Calgary

Abdullah Al-Ani, University of Calgary

Emi Sanders, Alberta Health Services

Andrew Crichton, University of Calgary

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