Central Visual Field Defects in Patients with Distinct Glaucomatous Optic Disc Phenotypes

Area of Science:

• Ophthalmology
• Optometry
• Visual Neuroscience

Background:

• Glaucoma is a leading cause of irreversible blindness.
• Optic disc morphology is a key indicator in glaucoma diagnosis and progression.
• Understanding visual field defects across different optic disc phenotypes is crucial for early detection and management.

Purpose of the Study:

• To investigate and compare central visual field (VF) defects across four distinct phenotypes of glaucomatous optic discs.
• To determine if specific optic disc morphologies are associated with particular patterns or severities of VF loss.

Main Methods:

• A cross-sectional study involving 448 eyes of 309 patients with definite or suspected glaucoma.
• Optic disc phenotypes (focal ischemic, generalized cup enlargement, myopic glaucoma, senile sclerotic) were identified.
• Standard 24-2 and detailed 10-2 visual field tests were performed and analyzed using mean deviation (MD) and pattern standard deviation (PSD) criteria.

Main Results:

• While overall 24-2 VF mean deviation was similar across phenotypes, generalized cup enlargement (GE) eyes showed better 10-2 VF MD and lower PSD values.
• The prevalence of abnormal 10-2 VF defects was highest in focal ischemic (FI) eyes (78.5%) and lowest in GE eyes (50.5%).
• In glaucoma suspects and mild glaucoma, FI and myopic glaucoma (MY) phenotypes exhibited a higher prevalence of abnormal 10-2 VF defects compared to GE.

Conclusions:

• Central visual field loss severity and prevalence differ significantly among glaucomatous optic disc phenotypes.
• Focal ischemic and myopic glaucoma phenotypes are more susceptible to central VF loss, particularly in early disease stages.
• Combined 10-2 and 24-2 VF testing may be particularly beneficial for patients with FI and MY optic disc phenotypes to detect early central vision changes.