Patterns of visual field defects in chronic angle-closure glaucoma with different disease severity

Abstract

Purpose: To evaluate the patterns of visual field defects in patients with chronic angle-closure glaucoma (CACG) with varying extent of optic nerve damage.

Design: Prospective, consecutive, observational case series.

Participants: One hundred forty-six Asian patients with well-controlled CACG.

Methods: Visual field tests were performed using program 24-2 of the Humphrey Field Analyzer (Humphrey Instruments, San Leandro, CA) with the Swedish interactive thresholding algorithm standard. One hundred ten eligible visual fields were scored with the system adopted by the Advanced Glaucoma Intervention Study and were categorized into 4 groups accordingly: mild, moderate, severe, and end-stage. Each hemifield was divided into the nasal, paracentral, and arcuate areas, and field loss that involved respective areas was defined as nasal step, paracentral scotoma, and arcuate scotoma.

Main outcome measures: The distribution of field defect patterns in each group was evaluated. The mean deviation (MD) was compared among the 3 areas within one hemifield and between each pair of corresponding areas across the median raphe.

Results: The nasal area was the most commonly damaged area in the mild group, being noted in 52% of eyes in the superior hemifield and 58% of eyes in the inferior hemifield. In the moderate group, field loss involving both the nasal and arcuate areas dominated the superior hemifield, whereas field loss involving all three areas dominated the inferior hemifield. The MD of the nasal area was the worst among the three areas in each hemifield of the mild and moderate groups, as well as in the inferior hemifield of the severe group (all P < 0.001). There were no significant differences in the MD of each area between the superior hemifield and their inferior counterparts. However, the superior hemifield as a whole showed a better MD than the inferior hemifield (P=0.034) in the mild group.

Conclusions: Visual field loss that involved the nasal area was the most common pattern in the early stage of CACG. The MD of the nasal area was worse than those of the arcuate and the paracentral areas within the same hemifield in the mild, moderate, and severe groups of CACG patients.