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Assessing Early Stage Open-Angle Glaucoma in Patients by Isolated-Check Visual Evoked Potential
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Asymmetric Patterns of Visual Field Defect in Primary Open-Angle and Primary Angle-Closure Glaucoma
Siamak Yousefi1,2, Hiroshi Sakai3, Hiroshi Murata1
1Department of Ophthalmology, University of Tokyo, Tokyo, Japan.
Investigative Ophthalmology & Visual Science
|April 7, 2018
Summary
Primary open-angle glaucoma (POAG) shows more pronounced superior visual field loss than primary angle-closure glaucoma (PACG). This hemifield asymmetry is more evident in POAG across all disease stages.
Area of Science:
- Ophthalmology
- Glaucoma Research
- Visual Field Analysis
Background:
- Glaucoma is a leading cause of irreversible blindness.
- Primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG) are distinct forms of the disease.
- Understanding visual field (VF) loss patterns is crucial for diagnosis and management.
Purpose of the Study:
- To compare the hemifield asymmetry of VF loss in POAG versus PACG.
- To analyze these differences across all glaucoma severity levels.
Main Methods:
- Included 522 eyes of 327 POAG patients and 375 eyes of 204 PACG patients.
- Calculated mean total deviation (TD) values in Glaucoma Hemifield Test (GHT) regions for early, moderate, and advanced stages.
- Compared TD differences between superior and inferior hemifields and analyzed pattern standard deviation (PSD) versus mean TD (mTD) relationship.
Main Results:
- POAG eyes showed greater superior hemifield loss than inferior, especially in moderate/advanced stages.
- PACG eyes had significantly fewer regions with superior hemifield loss compared to POAG.
- POAG eyes exhibited higher PSD values for given mTD values than PACG eyes.
Conclusions:
- Both POAG and PACG demonstrate more superior than inferior VF damage.
- This superior hemifield predilection is significantly more pronounced in POAG compared to PACG.
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