Correlating of the visual field index with mean deviation and pattern standard deviation in glaucoma patients

Abstract

The purpose of our study was to evaluate the correlation between the new index - visual field index (VFI) and mean deviation index (MD) and pattern standard deviation (PSD) in patients with glaucoma. MD, PSD and VFI were calculated in data about 103 eyes obtained from a cross-sectional study in 103 eyes of 58 patients with mild to severe glaucoma or ocular hypertension. The correlation of VFI to MD, PSD was evaluated with linear regression models, and the coefficient of determination (r) was calculated. The result showed that the average values of VFI, MD and PSD were 78.76%, -10.22 dB and 4.56 dB respectively. The VFI and the MD were linearly correlated with r = 0.984. For the patients with VFIs below 90%, the correlation with the MD was better than for the patients with VFIs 90% and above (r = 0.986 vs 0.571). There was no statistically significant difference in VFI value between the group with cataract and the group without cataract (p > 0.05) but MD varied significantly between these two groups (p < 0.05). For the PSD, the correlation for the patients with VFIs 90% and above was greater than for the patients with VFIs below 90% (r = -0.982 vs -0.196). In conclusion, VFI was linearly correlated with MD and PSD. VFI seems to be less affected by cataract than MD.