Title: Asymmetric Patterns of Visual Field Loss in Primary Angle Closure Glaucoma, High Tension Glaucoma, and Normal Tension Glaucoma
Abstract: Abstract The data directly comparing the spatial pattern of VF defects between primary angle-closure glaucoma (PACG), high-tension glaucoma (HTG) and normal-tension glaucoma (NTG) is not available. We aim to compare the asymmetric patterns of VF defects in patients with PACG, NTG and HTG across different severity levels. A total of 162 eyes of 114 patients with PACG, 111 eyes of 74 patients with HTG and 148 eyes of 102 patients with NTG were included. VF examinations were performed with standard automated perimetry (HFA, SITA-standard strategy, 24-2), and defects were categorized into 3 stages (early, moderate, and advanced) and each hemifield was divided into 5 regions according to Glaucoma Hemifield Test (GHT). The mean total deviation (TD) of each GHT region was calculated. The relationship between the values of pattern standard deviation (PSD) and mean TD was assessed. In the early stage, nasal region of PACG, central region of HTG and all five regions of NTG in the superior hemifield had significantly worse mean TD than their counterparts in the inferior hemifield. In the moderate stage, three regions of NTG in the superior hemifield had significantly worse mean TD than their inferior counterparts. In the advanced stage, central region of PACG, and central and paracentral regions of HTG in the superior hemifield had significantly worse mean TD than their inferior counterparts. When participants were matched by age, sex and mean deviation, in PACG and HTG eyes, all 5 GHT regions in the superior hemifield had worse mean TD than that that of their inferior-hemifield counterparts; however, the differences were not statistically significant. In NTG eyes, the paracentral, nasal, arcuate 1 and arcuate 2 regions in the superior hemifield had significantly worse mean TDs than their inferior counterparts. The superior hemifield is affected more severely than the inferior hemifield in all 3 subtypes of primary glaucoma. This asymmetric tendency was more pronounced in NTG compared to PACG and HTG.