Glaucoma Glaucoma is a disease that affects the eye. It causes damage to the optic nerve which sends images to the brain. The nerve is damaged by intraocular pressure, pressure in the eye. If left untreated, glaucoma can cause vision loss. There are two main types of glaucoma, open-angle or wide-angle glaucoma and angle-closure or narrow angle glaucoma. Open-angle glaucoma is the more common of the two. In open-angle the eye appears normal, however, fluid does not flow properly through the trabecular passage. Angle-closure is a sudden buildup in eye pressure. Drainage is bad because the space between the iris and cornea is too small. There are sixty million people worldwide with glaucoma. There are 2.2 million in the United States. 8.4 million people were blind from glaucoma in 2010. Glaucoma can occur at any age but people that are over the age of 45 have a higher risk of getting it. People of different ethnicities have higher risks of glaucoma. The groups at risk are African Americans, Hispanic and Asian populations. Also if there has been prior injury to the eye there are higher risks. The symptoms of Glaucoma change according to the different types. Open-angle glaucoma only has one symptom. That symptom is the loss of sight. In most cases peripheral vision is lost before the central vision. The problem is that the patient may not notice the loss of vision and the disease will get severe. Closed-angle glaucoma has more mild symptoms, however there are severe symptoms. The symptoms of CAG include vision suddenly getting blurry, pain, nausea, and halos around lights. Symptoms can affect either one eye or both. Some symptoms of congenital glaucoma include watery eyes, cloudy appearance to the eye, and enlarged eye size. There are multiple ways that a doctor can test for glaucoma. These different procedures are aided by tools to help image the eye. These tools can expose the disease before symptoms occur. The first type is a tonometry. Tonometry measures the pressure of the eye. The patient sits resting their chin and forehead against rests to keep the head steady. In certain forms a probe is placed on the cornea to test the pressure. In a no touch tonometry a puff of air is blown in the eye. Next is a visual field test. This form is useful in testing because in glaucoma patients often lose peripheral vision first. This type of test can help determine if the vision is being lost. In this test the patient is asked to look at a computer screen and press a button whenever they saw a flash of light. With that information doctors can see the field of vision. One of the most important methods in diagnosing glaucoma is an ophthalmoscopy. The doctor can look at the optic nerve through the pupil. Doctors can then see if glaucoma is there or how bad it is. There are many different procedures of laser surgery for glaucoma. The first of these is a laser iridotomy. A laser iridotomy is where a hole is made in the iris to allow fluid drain normally. Next is Laser trabeculoplasty. This is only done in open-angled. Laser burns on the angle make a better passage for fluid to drain. It only lasts for around two years. The procedure would then be redone. Laser trabeculoplasty has two types, argon laser trabeculoplasty and