Automated suprathreshold screening for glaucoma: the Baltimore Eye Survey

Area of Science:

• Ophthalmology
• Public Health
• Medical Technology

Background:

• Glaucoma is a leading cause of irreversible blindness worldwide.
• Early detection and intervention are crucial for managing glaucoma and preventing vision loss.
• Population-based screening can identify individuals at risk in the community.

Purpose of the Study:

• To assess the effectiveness of automated suprathreshold perimetric screening for glaucoma detection.
• To evaluate this screening method within a population-based survey of ocular disorders.
• To compare the performance of automated visual field testing against other glaucoma screening methods.

Main Methods:

• A population-based sample of 4,735 adults aged 40+ underwent automated suprathreshold visual field testing (Humphrey Field Analyzer, Full Field 120 program).
• Subjects with abnormal results or other risk factors (e.g., high intraocular pressure, optic disc damage) were referred for ophthalmologist examination.
• Sensitivity and specificity of the automated test were calculated and compared to non-field parameters.

Main Results:

• Automated visual field testing had a median duration of 7.25 minutes per eye.
• Abnormal screening results were found in 26% of subjects, with confirmed defects in 9.5% leading to referral.
• With 90% specificity, the automated test's sensitivity for detecting glaucoma was 52%, outperforming intraocular pressure and optic disc measurements alone.

Conclusions:

• Automated suprathreshold perimetry is a more effective screening tool for glaucoma than non-perimetry-based methods.
• Despite its effectiveness, several logistical weaknesses were identified in implementing this visual field screening approach.
• Further refinement of automated perimetry is needed for optimal integration into population-based glaucoma screening programs.