Which parts of vision are usually lost first in primary open-angle glaucoma?

In primary open-angle glaucoma (POAG), the early stages of the disease are typically characterized by a lack of noticeable symptoms. When visual loss does occur, it begins in the peripheral parts of the visual field.1

Because the progression of optic nerve damage is slow and painless, central vision is generally preserved until the later stages of the disease. It is ethically imperative to prioritize early diagnosis through regular screenings, such as the measurement of intraocular pressure, because any vision lost to glaucoma is permanent and cannot be restored.1