Primary open-angle glaucoma often develops painlessly and gradually. There are no early warning signs. It can gradually diminish your vision without you knowing it. Acute angle-closure glaucoma may have symptoms such as nausea, eye pain, red eyes, blurred vision and haloes around lights.
A comprehensive ocular health examination is often the only way to detect glaucoma. Your visual acuity can remain a sharp 20/20 in the beginning stages of this condition. Your optometrist will include in your examination a simple and painless procedure called tonometry, which measures the internal pressure of your eye. Your optometrist will also look into your eye to observe the health of the optic nerve.