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Assessing Early Stage Open-Angle Glaucoma in Patients by Isolated-Check Visual Evoked Potential
Published on: May 25, 2020
Relationship between ocular pulse amplitude and glaucomatous central visual field defect in normal-tension glaucoma
Marvin Lee1, Eun-Hyung Cho, Ho Min Lew
1Department of Ophthalmology, Ajou University School of Medicine, Suwon, Korea.
Journal of Glaucoma
|February 28, 2012
Summary
In normal-tension glaucoma (NTG), increased ocular pulse amplitude (OPA) is linked to more central visual field (VF) defects. This finding suggests OPA may indicate disease progression in early stages.
Area of Science:
- Ophthalmology
- Glaucoma Research
- Visual Neuroscience
Background:
- Normal-tension glaucoma (NTG) is a form of glaucoma where intraocular pressure is not elevated.
- Central visual field defects can be challenging to detect in early stages of NTG.
- Ocular pulse amplitude (OPA) is a measure of the pulsatile changes in intraocular pressure.
Purpose of the Study:
- To investigate the relationship between central visual field (VF) defects and ocular pulse amplitude (OPA) in early normal-tension glaucoma (NTG).
Main Methods:
- Retrospective study of 100 eyes (54 NTG patients, 46 normal subjects).
- OPA measured using dynamic contour tonometry.
- NTG patients categorized into central VF-invading and central VF-sparing subgroups based on visual field tests.
Main Results:
- No significant difference in OPA between NTG and normal groups.
- The central VF-invading group showed higher intraocular pressure (IOP) and OPA compared to the central VF-sparing group.
- OPA positively correlated with indices representing central field defects in NTG patients.
Conclusions:
- Increased OPA is associated with more centrally located visual field defects in NTG patients with mild visual field loss.
- OPA may serve as a potential biomarker for central visual field progression in early NTG.
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