Differences in Screening Indicator Performance for Primary Angle Closure and Primary Angle Closure Diseases: The...

Area of Science:

• Ophthalmology
• Medical Imaging
• Public Health

Background:

• Primary angle closure disease (PACD) is often nonprogressive, while primary angle closure with or without glaucoma (PAC/G) presents a higher risk.
• Current screening methods may not adequately differentiate between these conditions, potentially leading to missed diagnoses of more severe forms.

Purpose of the Study:

• To compare screening indicator profiles for PACD and PAC/G.
• To identify differences that could inform a shift in screening priorities towards higher-risk PAC/G cases.

Main Methods:

• A population-based cross-sectional study involving adults aged ≥35 years.
• Standardized eye examinations including gonioscopy and anterior-segment optical coherence tomography (AS-OCT).
• Univariable and multivariable logistic regression models were used to assess AS-OCT parameters for detecting PACD and PAC/G.

Main Results:

• Anterior-segment OCT parameters, specifically angle opening distance (AOD) and trabecular-iris space area (TISA), showed stronger associations with PAC/G than PACD.
• TISA at 500 μm (TISA500) demonstrated the highest discriminative value for PAC/G (AUROC 0.91), while TISA at 750 μm (TISA750) was best for PACD (AUROC 0.88).
• Multivariable models for PAC/G identified a profile including lower iris curvature and narrower angle width, achieving an AUROC of 0.908.

Conclusions:

• Screening for PAC/G may require different parameters than PACD, as angle measurements can be underestimated and iris curvature overestimated when using PACD-focused criteria.
• Anterior-segment OCT-derived models show feasibility and promise for improving PAC/G screening in population-based settings.