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Updated: Jul 2, 2026

Assessing Early Stage Open-Angle Glaucoma in Patients by Isolated-Check Visual Evoked Potential
Published on: May 25, 2020
The utility of symptoms in identification of primary angle-closure in a high-risk population
Ee Lin Ong1, Jamyanjav Baasanhu, Winifred Nolan
1Department of Epidemiology and International Eye Health, UCL Institute of Ophthalmology, London, United Kingdom.
Objective:
To examine the frequency of symptoms associated with primary angle closure in an East Asian population with high rates of disease.
Design:
Population-based survey.
Participants:
One thousand adults from rural and urban provinces of Mongolia were examined.
Methods:
A standard questionnaire was used to determine a history of symptoms of angle closure. All participants underwent applanation tonometry, gonioscopy, and slit-lamp examination by the same observer. The frequency of symptoms was compared between normal subjects and those in 3 high-risk or affected groups: gonioscopically confirmed occludable angles, peripheral anterior synechiae (PAS) detected on gonioscopy, and anterior chamber depth of less than 2.5 mm.
Main Outcome Measures:
The frequency of symptoms associated with primary angle closure.
Results:
Symptoms of visual disturbance and ocular pain traditionally linked with angle closure were reported frequently by both normal and potentially affected people. Intermittent blurring of vision at night was the only common symptom of angle closure that was significantly more frequent in people with narrow angles and PAS (P = 0.004, 48.4% vs. 31.0% narrow angles; P = 0.001, 54.3% vs. 30.6% PAS), but not in those with shallow anterior chambers (P = 0.670, 38.3% vs. 30.9%).
Conclusions:
Direct questioning about symptoms associated with angle closure identified high rates of positive responses in both affected and unaffected groups. Although the rate of symptoms tended to be higher in affected people, none of these symptoms were specific enough to be considered useful as a diagnostic criterion.
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