What is Glaucoma?
Glaucoma is the most preventable source of vision loss in the developed world and specifically impacts millions of Americans as one of the primary causes of blindness in the United States. Glaucoma is not a single eye disease, but rather a collection of eye conditions causing optic nerve damage, which may lead to vision loss.
High Intraocular Pressure in Glaucoma
Typically, but not always, an uncommonly high pressure (intraocular pressure), which is due to a buildup of fluid (aqueous humor) that flows in and out of the eye, causes this optic nerve damage. This fluid usually leaves the eye through a drainage system at the angle where the iris and the cornea intersect, but when the drainage system does not work correctly, the fluid is unable to filter out of the eye at the normal rate, and pressure increases within the eye.
Silent Loss of Vision with Glaucoma
Unfortunately, there are typically no signs or symptoms of glaucoma until actual loss of vision, which is usually due to the gradual pace of progression that characterizes most forms of the disease. Often, a person may notice no sign of vision loss until the disease is at an advanced stage, and the most common type of glaucoma is called primary open-angle glaucoma. It is important to have regular eye examinations, because regular intra-ocular pressure measurements and early diagnosis and treatment can minimize optic nerve damage and subsequent loss of vision.
Why Have Glaucoma Surgery?
A patient may need surgery to treat glaucoma if medications are ineffective or not an option. Glaucoma surgery decreases the pressure in the eyes by opening the obstructed drainage angles or creating a new opening that allows the fluid to leave the eye through. Sometimes, a single surgery does not sufficiently lower the pressure within the eye, and either multiple surgeries are required or medication is necessary post surgery. Unfortunately, surgery cannot reverse vision loss.
Read about the two general types of glaucoma surgery, Glaucoma Laser Surgery and Conventional Glaucoma Surgery (Filtering Microsurgery).