Abstract
Purpose :
To investigate correlations between the exploratory visual search performance (EVSP), and visual field (VF) loss in patients with primary open-angle glaucoma (POAG) and normal visual acuity.
Methods :
Seventeen POAG patients (age range: 40 to 78 years old; mean 65±11 years old) and normal visual acuity (better than 0.2 logMAR) yielded a complete comprehensive ophthalmological examination, including log MAR best-corrected visual acuity (BCVA) measurement, and Humphrey VF test (SITA-Fast 24.2). An explorative search digit-based task was performed using a custom software that quantify the duration (s) until patients found the number “4” on a random array of digits (“0 – 9”; 12-point Arial font) distributed on the screen. Twenty normally-sighted subjects (age range: 36 to 71 years old; mean 56±10 years old) were evaluated to serve as controls. Spearman r test was used to investigate correlations between EVSP (mean response time from 9 screen tests) and VF sensitivity loss, considering mean deviation (MD) and the average values of three sectors of the total deviation plot: central (16 points around fixation), non-central superior, and non-central inferior (all superior and inferior points beyond central sector, repectively).
Results :
Patients mean ± SE BCVA was 0.09 ± 0.02 logMAR (vs controls: 0.06 ± 0.02 log MAR; p= 0.29), and visual field MD ranged from -1.5 to -27.1 dB (-10.5 ± 1.8 db vs -1.2 ± 0.3 dB in controls, p< 0.001). There was a significant increased EVSP in patients during the search task (26.8 ± 1.9 s vs 10.9 ± 1.8 s in controls; P<0.0001). All VF scores studied showed a significant negative correlation with EVSP only in the patients group [MD: r= -0.68 (p= 0.0025); central: r= -0.71 (p= 0.0014); superior: r= -0.58 (p= 0.0157); inferior: r= -0.67 (p= 0.0033)]. Although mean age was significant different between groups (p=0.004), age (r= 0.52; p= 0.0169) and BCVA (r= 0.50; p= 0.0237) correlated with EVSP only in controls.
Conclusions :
POAG patients showed lower EVSP in a digit searching task, and the difficulty presented by them increases as VF scores worsen. This data suggest that the EVSP results from this digit-based search task may be further used for the development of new software aimed to evaluate limiting VF loss in daily activities of glaucoma patients.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.