Glaucoma is a group of eye diseases of the optic nerve involving loss of cells located at in the retina, the back of the eye. If glaucoma is untreated it leads to permanent damage of the optic nerve and visual field loss, which could lead to blindness.
Open angle glaucoma (OAG) or chronic glaucoma is the most common form of glaucoma in the United States and in the United Kingdom. Open angle progresses more slowly so the patient might not notice it until the disease has progressed quite far. A lot of the time the visual field deteriorates gradually over a long time and may only be recognized when it has become advanced. Once lost this damaged visual field can never be recovered. Glaucoma is the second leading cause of blindness world wide. Glaucoma affects one in two hundred people aged fifty and younger, and one in ten over the age of eighty.
Closed angle glaucoma (CAG) or acute glaucoma is less common, accounting for about 10% of all glaucoma cases in the United States. In closed angle glaucoma, the iris and the lens block the movement of fluid between the chambers of the eye causing pressure to build up and the iris to press on the drainage system (trabecular meshwork). It could cause sudden blurred vision with pain and redness, usually in one eye first; symptoms may also include nausea and vomiting. A related type, acute closed angle glaucoma, is often an emergency situation and needs immediate medical care to prevent permanent damage to the eye. Angle closure appears suddenly and usually with painful side effects so is usually quickly diagnosed – although damage and loss of vision can also occur very suddenly.
Congenital glaucoma is a rare form of glaucoma that is present in some infants at birth. Glaucoma that develops during the first few years of life is called infantile glaucoma. Infants with congenital or infantile glaucoma usually have cloudy eyes that are sensitive to light and have excessive tearing. Symptoms may not develop until 6 months to 1 year after birth. If the problem is not detected early and treated, the child may have severe vision loss and may go blind. People between the age of 3 years and young adulthood can develop a similar type of glaucoma called juvenile glaucoma.
Damage to the optic nerve is thought to be caused by increased pressure in the eye. This may result from excess fluid (aqueous humor) building up in the eye because the eye produces too much or drains too little of the fluid. However, many cases of glaucoma develop without increased IOP. In these cases, decreased blood flow to the optic nerve may cause the damage. Glaucoma may develop after an eye injury, after eye surgery, from the growth of an eye tumor, or as a complication of a medical condition such as diabetes. Certain medications (corticosteroids) may cause glaucoma when they are used to treat eye inflammation or other diseases. Glaucoma that develops as a result of another condition is called secondary glaucoma.
Your health professional will take a medical history and do a physical exam. If glaucoma is suspected, you usually will be referred to an eye specialist (ophthalmologist) for further testing and treatment. The initial evaluation by a specialist may require up to 3 visits.
The treatment for glaucoma concentrates on slowing the damage to the optic nerve by lowering the pressure in the eyes. Eye drops and other medications are also used to treat Glaucoma. Often laser treatment or surgery is needed.