Abstract
Purpose :
To investigate the impact of refractive error (RE) on visual field (VF) mean sensitivity (MS) and reliability in a cohort of healthy subjects.
Methods :
A cross-sectional analysis was performed on a diverse sample of healthy subjects, utilizing the TEMPO/IMOvifa (Topcon Healthcare/CREWT Medical Systems, Tokyo, Japan), a binocular visual function analyzer with the specific settings (stimulus size III, AIZE-R test strategy, and ON tracking). Every subject underwent 24-2 testing using TEMPO/IMOvifa, while a subgroup of subjects also completed 24-2 SITA-FAST testing on the Humphrey Field Analyzer, Carl-Zeiss Meditec (HFA). Subjects were categorized as myopes (≤-0.50 diopters (D)), hyperopes (≥0.50 D), or emmetropes (between -0.50 D and 0.50 D) based on spherical equivalence.
Results :
The study included 119 subjects (119 eyes; ages 22-93 years) who underwent TEMPO/IMOvifa VF testing. RE ranged from -5.25 to +3.00 D and maximum cylindrical power was 2.50 D. The MS (mean ± SD) was 29.25 ± 1.23 decibels (dB) for myopes, 28.41 ± 0.99 dB for hyperopes, and 29.06 ± 1.29 dB for emmetropes. Hyperopes exhibited significantly lower MS compared to myopes (p=0.001) and emmetropes (p=0.026). Myopes had a trend of higher fixation losses (FL; 1.55%) compared to emmetropes (0.58%) and hyperopes (1.46%). Emmetropes showed a trend of higher false positives (FP; 1.35% vs. 0.71% for hyperopes and 0.59% for myopes). False negative (FN) percentages were similar among the three groups (p>0.05 for all). Further analysis within the myopic group revealed that moderate myopes (-3.00 to -6.00 D) had a trend of higher FL (2.44% vs. 1.24%) but similar FP (0.33% vs. 0.69%) and FN (0.11% vs. 0.08%) when compared to low myopes (-0.50 to > -3.00 D). A subgroup of 23 subjects underwent HFA VF testing. Among these subjects exhibiting variable RE, there was a consistent trend of higher FL, FP, and FN when using HFA as opposed to TEMPO/IMOvifa.
Conclusions :
Although not clinically meaningful, hyperopes demonstrated significantly lower MS than myopes and emmetropes. Further, trends indicating higher FP in emmetropes and increased FL in moderate myopes were observed. These findings suggest that RE should be considered in the interpretation of VF testing outcomes, even in the absence of ocular pathologies.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.