Laser surgery won't cure your glaucoma (glah-CO-muh), but in most cases it can bring eye pressure under control by improving drainage of fluid from the eye. Before laser surgery was available, glaucoma surgery required opening your eye with a surgical instrument and cutting away parts of the internal eye to attempt to control the pressure flow. In general, laser surgery is safer because it's less invasive. Laser surgery performed as the initial treatment for glaucoma can be as effective as medication. An advantage is that the side effects from surgery are usually temporary and cause no long-term problems, while those from medications can be ongoing and adverse. Because it doesn't cure glaucoma, within two to five years about half of patients need either additional surgery or new medications. In treating glaucoma using laser surgery, the surgeon uses an instrument, usually a YAG (YAG) laser, to burn 80 to 100 tiny holes in the drainage area. A tiny scar forms, which increases fluid outflow. The procedure usually takes half an hour or less, causes almost no discomfort, and usually has very few complications. Both eyes are never done at the same time, in case any complications do arise. Some of these can include inflammation, bleeding, or worsening of an existing cataract. In addition, the surgery can sometimes fail to control, or even reduce, the pressure inside your eye. In some patients, pressure can actually increase after surgery, and in a few cases, the increased pressure is permanent, and vision loss can occur. About a third of patients also develop adhesive-like substances that cause the iris to stick to part of the cornea.