Glaucomas, except for normal tension Glaucoma, are a group of eye diseases that share the characteristics of high intra-ocular pressure. Eyeballs, very much like footballs or automobile tires or blood vessels, have internal pressure, usually from 8-21 mm/Hg. That level of pressure is essential for the circulation of blood in nutrient blood vessels. If pressure rises above that level, blood circulation may become compromised, which jeapordizes the function of tissues inside the eye (optic nerve and retinal cells). Since damages caused by glaucoma are usually not reversible, early detection and management of this group of diseases is beneficial. Most glaucoma cases do not cause any symptoms noticeable by the patients at the early stages, so regular eye exams by an eye specialist is quite essential to detect the existence of such a condition. In some forms of glaucoma ( acute closed angle ), eyes become painful, which alerts the person to see an eye doctor.

Glaucomas can be

-congenital

-juvenile

-secondary (due to ocular disease, anatomic abnormality of the eye, some systemic diseases, from medication)

-idiopathic (without any known cause)

Glaucomas, due to their potential to cause blindness, have been a great concern and challenge to patients and eye doctors. Fortunately, through recent advances in diagnostic methods and available treatment modalities and medications, some forms of this group of eye diseases can be controlled, its progression slowed down and vision can be restored for longer times.

Inside the eyeball, similar to the brain, a nutrient fluid, is constantly secreted, circulated and drained out of the eye. This fluid, also known as aqueous, supplies nutrients to the cornea and crystalline lens. In most glaucomas the porous drainage system located behind the cornea (angle) does not function well. This causes impeded drainage of aqueous through the angle pores, building up pressure above the normal range, which can be deleterious to vision.The high intra-ocular pressure gradually damages the optic nerve leading to loss of peripheral vision which is rather unnoticible to the patient.
The goal and the only available treatment option for primary open glaucoma is to relieve any obstacle to the process of drainage, and therefore bring the elevated pressure down to a normal level.

The most common type of glaucoma is called primary open angle glaucoma which is seen in elderly people. It is initially asymptomatic, and can only be diagnosed by eye doctors. The exact mechanism for the causation of this type of glaucoma is not yet understood. There are degenerative changes in the drainage tissue at the angle which makes the exit of the aqueous out of the eye harder. Also it is not known whether the damages to the optic nerve and retinal cells are the direct effect of high pressure, or some disease process at the retinal or optic nerve level that is responsible for the vision problem. Primary glaucoma is slowly progressive and, if not treated, will cause blindness in the course of several years. Eye condition can be managed and vision deterioration prevented for many years, if patients pay frequent visits to eye practitioners.

There are few risk factors that people should be aware of, among them family history of same type of glaucoma, ethnicity (African Americans and Hispanics have higher risk), diabetes, cigarette smoking and corneal central thickness, are examples.

People with glaucoma should stop smoking. Elderly patients with glaucoma need to have lower eye pressure, preferably safely around 12-15.

Ophthalmologists use one or a combination of the three modalities of treatment in management of glaucoma diseases.

1- Pressure reducing agents in the form of eye drops

2- Laser to the angle or the iris

3-Different methods of surgeries to help increase the aqueous outflow and reduce the high pressure of the eye.

The most popular and utilized modality by many eye physicians is the use of eye drops. Eye drops reduce the pressure by 4 different mechanisms, depending on the action and the site of the eye they influence. The selection of the type and the quantity of these drops depend on the characteristics of the patient’s glaucoma and to some extent, to the treating eye physician’s opinion and expertise. Medical treatment (by eye drops) is quite effective in management of primary glaucoma in the majority of cases, and if pressure can not be reduced to satisfactory levels to prevent progression of the condition, then laser to the angle or surgery is advisable.