Comparative optic disc analysis in normal pressure glaucoma, primary open-angle glaucoma, and ocular hypertension

Area of Science:

• Ophthalmology
• Glaucoma Research
• Optic Nerve Imaging

Background:

• Glaucoma is a leading cause of irreversible blindness.
• Optic nerve damage and parapapillary atrophy are key indicators in glaucoma diagnosis and progression.
• Differentiating between primary open-angle glaucoma (POAG) and normal-pressure glaucoma (NPG) is crucial for management.

Purpose of the Study:

• To compare optic disc and parapapillary atrophy characteristics in eyes with ocular hypertension, POAG, and NPG.
• To investigate differences in NPG, including a subset with autoimmune markers.
• To assess the relationship between neural rim damage and parapapillary atrophy in different glaucoma types.

Main Methods:

• Analysis of 392 eyes with ocular hypertension, 394 with POAG, and 135 with NPG.
• Evaluation of nerve fiber layer hemorrhage, retinal arteriolar narrowing, and optic disc/parapapillary atrophy parameters.
• Delineation of parapapillary atrophy into alpha and beta zones.

Main Results:

• Nerve fiber layer hemorrhage and arteriolar narrowing were more frequent in NPG compared to POAG and ocular hypertension.
• Zone beta of parapapillary atrophy was more prevalent in NPG.
• Despite more advanced damage in NPG, correlations between neural rim area and parapapillary atrophy were similar in NPG and POAG.

Conclusions:

• Parapapillary atrophy severity, including zone beta, increases with neural damage in glaucoma.
• The clinical appearance of optic nerve damage is consistent across POAG, NPG, and NPG subgroups.
• This suggests a common pathway or endpoint in glaucomatous optic neuropathy, irrespective of underlying mechanisms.