Symptoms and Signs of Primary Open-Angle Glaucoma (POAG)

Medical Author: John P. Cunha, DO, FACOEP
Medically Reviewed on 11/8/2021

Doctor's Notes on Primary Open-Angle Glaucoma (POAG)

Primary open-angle glaucoma (POAG) is the most common type of glaucoma. It is one of the leading preventable causes of blindness in the world, and it is the most common cause of blindness in African-Americans. In POAG, there is the characteristic optic nerve damage associated with open angles (the area between the iris and cornea) and elevated eye pressure. This is different from other types of glaucoma, which are associated with abnormal angles (for example, narrow-angle glaucoma, closed-angle glaucoma, primary congenital glaucoma, and other secondary glaucomas) or low eye pressures (normal tension glaucoma).

In the early stages, primary open-angle glaucoma may cause no symptoms. The main signs of primary open-angle glaucoma are

  • the presence of a thinned (atrophied) optic nerve and the presence of an open angle,
  • both of which can be seen using specialized instruments during an eye examination.

By the time symptoms of vision loss or blind spots in primary open-angle glaucoma occur the disease is usually in the later stages and irreversible optic nerve damage may have already occurred.

What Is the Treatment for Primary Open-Angle Glaucoma?

Primary open-angle glaucoma is treated with medications or surgery. Medications prescribed for open-angle glaucoma are designed to either increase the outflow of fluids in the eye or decrease the overall production of fluids in the eye in order to keep intraocular pressure under control. Drug combinations are often used to control intraocular pressure because they have a greater benefit than any single drug used by itself. Common drug classes used to treat open-angle glaucoma include:

  • Prostaglandins
    • Latanoprost
    • Bimatoprost
    • Tafluprost
  • Alpha adrenergic agonists
    • Brimonidine
    • Epinephrine
  • Cholinergic agonists
  • Rho kinase inhibitors
    • Netarsudil
  • Beta blockers
  • Carbonic anhydrase inhibitors
    • Dorzolamide
  • Combination products are available for several classes of drugs including most commonly:
    • Latanoprost-timolol
    • Travoprost-timolol
    • Dorzolamide-timolol
    • Brimonidine-timolol
    • Netarsudil-latanoprost

Some cases require a surgical procedure to keep intraocular pressure under control. Common glaucoma treatment procedures include

  • Laser therapy (trabeculoplasty) 
  • Argon laser trabeculoplasty 
  • Surgical therapy (trabeculectomy) with creation of a filtration bleb 
  • Placement of mechanical shunts

Must Read Articles:

REFERENCE:

Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.