This type of glaucoma is also known as acute glaucoma or narrow angle glaucoma. It is much more rare and the intraocular pressure usually goes up very fast. This occurs because the drainage canals get blocked or covered over. When this occurs the iris and cornea is not as wide and open as it should be. The outer edge of the iris bunches up over the drainage canals, when the pupil enlarges too much or too quickly. This can happen when entering a dark room.
This type of glaucoma is treated with surgery to remove a portion of the outer edge of the iris, to unblock the drainage canals. Usually this surgery is successful and long lasting.
Symptoms of angle closure glaucoma may include headaches, nausea, and rainbows around lights at night, eye pain, and very blurred vision. An angle closure emergency is needed when there is a sudden decrease of vision, extreme eye pain, headache, nausea and vomiting and glare or light sensitivity.