Glaucoma is defined as “an increase in pressure in the eye with a loss of vision.” The disease is painful in most cases, especially when the eye pressure is very high. The signs of glaucoma include: redness, cloudiness, tearing, loss of vision, an enlarged eyeball, unusual aggressiveness, lethargy, and loss of appetite. The normal physiology of the fluid in the eye calls for the fluid to be made in one structure behind the pupil (ciliary body), travel through the pupil, and exit out the space between the cornea and the iris. When the fluid cannot properly drain from the eye, the pressure in the eye is increased. An analogy would be a kitchen sink – if the drain is open and the water is running, there is no problem. However, if a plug is placed in the drain and the water keeps running, then the sink fills up with water and overflows! Some patients have primary glaucoma where there is no concurrent disease but some secondary causes of glaucoma include: inflammation, trauma, and tumors. All of these factors can obstruct the drainage of fluid from the eye.