Relationship Between the Pupil Diameter Measured With the Humphrey Perimeter and Functional Loss in Early Glaucoma

Abstract

Abstract: : Purpose: To analyse the relationship between pupil diameter as measured with the Humphrey perimeter and visual field damage in a group of glaucoma suspects and early glaucoma patients. Method: Values for pupil diameter (PD) and visual field global indices mean sensitivity (MS), mean defect (MD) and pattern standard deviation (PSD) were retrospectively obtained and correlated in 178 eyes of 89 subjects. Results: Mean PD was 4.57 mm (IC 95% 4.43 ; 4.71), mean MS was 26.35 dB (IC 95% 25.85–26.85), mean MD was –2.71 (IC 95% –3.14 ; –2.28) and mean PSD was 2.99 (IC 95% 2.73–3.25). PD and visual field global indices showed no correlation (n=178; Pearson and Spearman correlation coefficients). When the paired differences for PD and global indices between eyes of every subject were analysed (most damaged vs less damaged eye), a weak correlation was observed (ΔDP vs ΔMS: r = –0.300; rs = –0.111 ; ΔDP vs ΔMD: r = –0.301; rs = –0.114 ; ΔDP vs ΔPSD: r = –0.310; rs = –0.165). Conclusions: Results show that PD, as measured with the Humphrey perimeter doesn't correlate with functional loss and is not a sensitive indicator to detect interocular differences in early glaucoma subjects.

Keywords: pupil • perimetry • visual fields