There are different types of glaucoma, but they can be broadly divided into two groups: chronic open-angle and closed-angle.

  • Chronic open-angle glaucoma: is the most common form of glaucoma. The drainage angle of the eye becomes less efficient over time, and pressure within the eye gradually increases, possibly resulting in damage to the optic nerve. In some patients, the optic nerve becomes sensitive even to normal eye pressure and is at risk for damage. Treatment is necessary to prevent further vision loss. Risk of developing chronic open-angle glaucoma increases with age.
  • Open-angle glaucoma: typically has no symptoms in its early stages, and vision remains normal. As the optic nerve becomes more damaged, blank spots develop in the field of vision. You may not notice these blank spots during day-to-day activity until the optic nerve is significantly damaged and these spots become large.
  • Closed-angle glaucoma: occurs in certain eyes when the iris is very close to the drainage angle. These eyes are often small and farsighted, and the iris could be sucked into the drain and block it completely. Since the fluid cannot exit the eye, pressure can build up rapidly, resulting in acute closed-angle attack.

Symptoms may include:

  • Blurred vision
  • Severe pain
  • Headaches
  • Rainbow halos around lights
  • Nausea
  • Vomiting
This situation is a true eye emergency. If you have any of these symptoms constantly or even intermittently, call your ophthalmologist immediately. If not treated quickly, this type of glaucoma can result in blindness.