Angle-Closure GlaucomaThis type of glaucoma is also known as acute glaucoma or narrow angle glaucoma. It is much more rare and is very different from open-angle glaucoma in that the eye pressure usually rises very quickly. This happens when the drainage canals get blocked or covered over, like a sink with something covering the drain. With angle closure glaucoma, the iris 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. A simple test can be used to see if your angle is normal and wide or abnormal and narrow.Symptoms of angle-closure glaucoma may include headaches, eye pain, nausea, rainbows around lights at night, and very blurred vision.Treatment of angle-closure glaucoma usually involves either laser or conventional surgery to remove a small portion of the bunched-up outer edge of the iris. Surgery helps unblock the drainage canals so that the extra fluid can drain. If you have angle-closure glaucoma in one eye, doctors may go ahead and treat the other eye as a safety measure.In general, surgery for angle-closure glaucoma is successful and long lasting. Regular checkups are still important though, because a chronic form of glaucoma could still occur. Source: http://www.glaucoma.org/glaucoma/angle-closure-glaucoma.php