What are the key differences between primary open-angle glaucoma and acute angle-closure glaucoma in terms of symptoms, urgency, and treatment?

Primary open-angle glaucoma is chronic and usually painless because the intraocular pressure is not high enough to cause pain; it first affects peripheral vision, so people are often unaware and it is typically detected at a routine eye test. Acute angle-closure glaucoma is an ophthalmic emergency with extremely high intraocular pressure causing substantial pain, a red hard eye, cloudy cornea, and an unreactive pupil. Treatment for primary open-angle glaucoma is medical, using drops to lower intraocular pressure such as prostaglandin agonists or beta-blockers, with surgery if needed; acute angle-closure glaucoma requires urgent treatment with pilocarpine drops, intravenous acetazolamide, and laser peripheral iridotomy to prevent recurrence.

Primary open-angle glaucoma is the common chronic form. Raised intraocular pressure damages the optic nerve, but the pressure is not so high as to cause pain. Because it affects peripheral vision first, the person may not notice it until an optician finds it during a routine eye test. Risks include age, family history, African origin, diabetes, thyroid eye disease, and short-sightedness. Medical treatment lowers intraocular pressure, normally with topical prostaglandin agonists and/or beta-blockers, and surgery may be necessary in some cases. Acute angle-closure glaucoma is much less common and is an ophthalmic emergency. The intraocular pressure is extremely high, causing substantial pain. The eye is red and hard, the cornea is cloudy, and the pupil is unreactive. This condition requires urgent treatment with drops, including pilocarpine, and intravenous medication, commonly acetazolamide. Definitive treatment is peripheral iridotomy by laser surgery, which normally prevents recurrence. People over 40 years old or with a family history of glaucoma should have annual eye screening.