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Updated: May 10, 2026
07:11
Assessing Early Stage Open-Angle Glaucoma in Patients by Isolated-Check Visual Evoked Potential
Published on: May 25, 2020
The biometric study in different stages of primary angle-closure glaucoma
11] Department of Public Health and Institute of Public Health, National Yang-Ming University, Taipei, Taiwan [2] Department of Ophthalmology, Madou Sin-Lau Hospital, Tainan County, Taiwan.
Eye (London, England)
|June 22, 2013
Summary
Primary angle-closure glaucoma (PACG) is linked to shallower anterior chamber depth and thicker lenses. A-scan ultrasonography may help detect PACG early in primary angle-closure patients.
Area of Science:
- Ophthalmology
- Glaucoma Research
- Ocular Biometry
Background:
- Primary angle closure (PAC) and primary angle-closure glaucoma (PACG) are significant causes of vision loss.
- Understanding the ocular biometric differences between normal, PAC, and PACG eyes is crucial for risk stratification and early detection.
Purpose of the Study:
- To compare general and ocular biometric characteristics of normal, PAC, and PACG patients.
- To identify ocular parameters that may predict the risk of PACG development in PAC patients.
Main Methods:
- Retrospective review of 100 normal, 90 PAC, and 90 PACG eyes.
- Collection of general data (age, gender, systemic health) and ocular parameters (visual acuity, IOP, refraction, cup-to-disc ratio, ocular biometry).
- Ocular biometry using A-scan ultrasonography to measure anterior chamber depth (ACD), lens thickness (LT), axial length (AXL), lens/axial length factor (LAF), and relative lens position (RLP).
Main Results:
- Significant differences in age were observed across the groups.
- Anterior chamber depth (ACD) decreased, while lens thickness (LT) and lens/axial length factor (LAF) increased from normal to PAC to PACG.
- PACG eyes had significantly shallower ACD and thicker LT compared to PAC eyes. PACG also showed a more anteriorly positioned lens (RLP).
- Logistic regression identified shallower ACD (OR=3.59 per 0.2mm decrease) and increased LT (OR=1.30) as significant risk factors for PACG.
Conclusions:
- A shallower ACD, potentially due to altered relative lens position (RLP), and increased lens thickness (LT) may contribute to the progression from PAC to PACG.
- Ocular biometric differences between PAC and PACG suggest A-scan ultrasonography could be valuable for early PACG detection in PAC eyes.
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