Abstract
Purpose: :
To evaluate the relationship of foveal sensitivity threshold (FS), measured with standard automated perimetry and visual acuity (VA) in patients with visual acuity loss attributed to glaucoma, in normal patients and in glaucoma patients with minimal loss of VA.
Methods: :
All patients had undergone 24-2 SITA-standard automatic perimetry (HFA II, Carl Zeiss Meditec Inc., Dublin CA) with FS measurement. LogMAR best corrected visual acuity (BCVA) for each group was determined by manifest refraction or pinhole test. Normal patients had 0.0 logMAR visual acuity and Glaucoma Hemifield Test (GHT) within normal limits on perimetry. Glaucoma patients had GHT outside normal limits and were divided into groups with <0.3 logMAR visual acuity (glaucoma controls) and patients with visual acuity > 0.3 logMAR . Patients with retinal disease or visually significant cataract were excluded. For each group, FS was compared with BCVA using Spearman's correlation with Bonferroni correction (significant at p<0.017) and Mann-Whitney U test with Bonferroni correction (significant at p<0.017) was performed to determine significance of FS difference between groups.
Results: :
We identified 19 glaucoma patients with reduced VA (0.8 logMAR), 11 glaucoma controls (0.2 logMAR) and 20 patients without glaucoma and with normal VA (0.0 logMAR) (ANOVA: p<0.001). FS correlated with BCVA for patients with glaucomatous central vision loss (rho=-0.7, p=0.01), and trended toward a significant correlation for glaucomatous controls (rho=-0.6, p=0.07). Median FS was not significantly different for the glaucoma patients with (FS=22) and without (FS=20) significant VA loss (p=0.51) but FS differed between normal controls and each of the glaucoma groups (median FS: 36; p<0.001).
Conclusions: :
FS reflected decreased VA in eyes with glaucomatous loss of visual acuity. Foveal sensitivity measured with standard automated perimetry may be helpful in characterizing or confirming VA loss due to glaucoma.
Keywords: visual impairment: neuro-ophthalmological disease • visual acuity • visual fields