Correlation between hemifield visual field damage and corresponding parapapillary atrophy in normal-tension glaucoma

Abstract

Purpose: To evaluate the correlation between the superior or inferior half area of parapapillary atrophy (PPA) and the corresponding hemifield visual field damage (VFD) in normal-tension glaucoma.

Design: Cross-sectional study.

Methods: patients: One hundred nine eyes of 109 consecutive patients with normal-tension glaucoma. observation procedures: Topography parameters of the optic nerve head and PPA (zone beta) area were obtained with the Heidelberg Retina Tomograph (HRT), and VFD was evaluated with the 30 to 2 program of Humphrey Field Analyzer. The HRT parameters and PPA area were determined separately in superior and inferior half regions. main outcome measures: Partial correlation coefficients of the superior and inferior areas of PPA with refractive error, axial length, HRT parameters, and corresponding hemifield VFD.

Results: In simple correlation analyses, significant correlation was found between the inferior PPA area and the superior hemifield VFD (Spearman rank correlation coefficient; Rs = -0.32; P < .001) but not between the superior PPA area and the inferior hemifield VFD (Rs = 0.05; P = .6). Age, refractive error, axial length, and height variation contour were associated significantly with the total, superior, and inferior areas of PPA, respectively (P < .01). Multiple regression analyses showed that the superior PPA area was associated significantly with only axial length (P < .001), and the inferior PPA area was associated significantly with the axial length and the superior hemifield VFD (P < .001).

Conclusions: In patients with normal-tension glaucoma, only the inferior half area of PPA correlated significantly with glaucomatous VFD. Axial length and myopia were associated with both the superior and inferior half areas of PPA.