Abstract
Purpose :
To test the improvement in speed and accuracy of a perimetric strategy that integrates structural information using the Open Perimetry Interface (OPI).
Methods :
Data from ten healthy participants were collected using the Compass Automated Perimeter (CMP, CenterVue, Italy) through the OPI. A bespoke Shiny user interface (UI) was used to import Optical Coherence Tomography (OCT) scans collected with a Spectralis SD-OCT (Heidelberg Engineering, Heideberg, Germany) of the macula and the optic nerve head (ONH) , then align them with the fundus image captured by the CMP at the beginning of the test (Figure 1). The test was performed using a 10-2 grid centred on the fovea of each participant, aligned with the fovea-ONH axis. The UI also designed to the Ganglion Cell Layer (GCL) thickness corresponding to each test location, after accounting for GC displacement. Two perimetric strategies were tested: standard ZEST with population-based prior distributions, and a Structural-ZEST (S-ZEST), enhanced with individual OCT data to determine the starting parameters. The starting priors for S-ZEST were modelled using an independent dataset of glaucoma and healthy subjects[CD1] . Tests with both strategies were repeated twice, in random order. All fundus images were aligned with the first test to ensure spatial consistency of the tested locations. Test-retest variability was quantified with Bland-Altman plots. Bootstrap was used to calculate confidence intervals (CIs) and p-values to compare the widths of the 95%-Limits of Repeatability (LoR). Correlation between GCL thickness and sensitivity (dB) and the difference in test duration was calculated using linear mixed effect models. Agreement was quantified with the mean difference between the results of the two strategies, after averaging the two repetitions.
Results :
95%-LoRs for S-ZEST were similar between the two devices (p = 0.829, Figure 2). The structure-function correlation was significant for both strategies (p < 0.001), and very similar between S-ZEST (R2 = 0.24) and ZEST (R2 = 0.23). There was a small but stastcally significant mean difference in sensitivity between S-ZEST and ZEST (0.56 [0.35, 0.77] dB, p = 0.034). S-ZEST was 2.7 [1.2, 3.5] minutes faster than ZEST (p < 0.001, Figure 2).
Conclusions :
S-ZEST significantly reduced testing time without reducing repeatability in healthy observers. Further testing is required to validate this approach in patients with glaucoma.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.