Atrium Health Navicent Ophthalmology Macon

Glaucoma Screening & Treatment

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Glaucoma Types and Treatments

Glaucoma is a loss of vision from damage to the optic nerve, the major nerve from the eye to the brain. In most cases, the damage is by excessive fluid pressure within the anterior area of the eye; however, glaucoma can damage the eye even when such intraocular fluid pressure is normal.

In primary open-angle form of glaucoma which is more prevalent, pressure rises gradually with vision fading over time. A less common form, acute or angle-closure glaucoma develops quickly and usually painfully from blockage of normal fluid flow within the drainage channels in the eye. Other, rarer forms may relate to eye defects that develop before birth such as congenital glaucoma, eye injuries, tumors, or secondary effects of diabetes. Corticosteroid medications have precipitated cases of glaucoma.

Glaucoma is life-long but with proper treatment can prevent loss of vision. As many as 2.5 million Americans suffer from glaucoma, many of them unaware of it. Glaucoma tends to afflict families. It is five times more common in blacks than in whites. The risk of glaucoma also increases with age in people of all racial and ethnic backgrounds.


Both open-angle and angle-closure forms of glaucoma can cause blindness, but they present different symptoms:

  • In open-angle glaucoma cases, loss of vision is painless and gradual, and most patients are unaware of their problem until impairment is already substantial. The peripheral vision fades first. As larger areas disappear, tunnel vision can become so narrowed that only what is directly in front of the patient is visible. If untreated, even this narrow field of vision becomes blinded and, once lost, never restored.
  • In closed-angle glaucoma, the onset of symptoms, which may be blurred vision, pain, and redness in the eye, severe headaches, halos around lights, corneal haziness, nausea, and fatigue, is sudden, severe, and often disabling.


Routine examinations of the back of the eye can discover changes in the appearance of the optic nerve suggesting open-angle glaucoma. If suspected, the examiner can confirm the suspicion by applying one or more tests:

  • Tonometry measures intraocular pressure with an instrument or by an airflow against the eyeball. Eye pressure measurement is by millimeters of mercury. Normal eye pressure is between 8 and 22 millimeters of mercury.
  • In perimetry, a visual field test that maps the field of vision, the patient looks straight ahead and indicates when able to see a moving light passing through the peripheral vision.
  • Optical coherence tomography measures the thickness of retinal nerve fibers. Glaucoma causes thinning of the nerve fiber layer.
  • In gonioscopy, a hand-held contact lens on the eye has a mirror that shows whether the angle where the iris meets the cornea is closed and blocked or open and wide or narrow.
  • Pachymetry is a simple, painless test to measure the thickness of the cornea, the clear window at the front of the eye. Corneal thickness can affect eye pressure readings. This measurement helps examiners interpret intraocular pressure readings accurately and develop appropriate treatment plans.

There is no diagnosis of open-angle glaucoma without evidence of optic nerve damage. Some cases display elevated intraocular pressure but no optic nerve damage. Not everyone with elevated pressure develops glaucoma, nor does everyone with glaucoma have elevated eye pressure.

Glaucoma cannot be prevented; however, glaucoma screening & treatment may identify early stages of glaucoma or elevated eye pressures. There is no medical consensus about who should be screened. African Americans over 40 years old seem to be most at risk. The family history of glaucoma and advanced age also increase the risk. Medicare covers glaucoma screening for diabetics, patients with family histories of glaucoma, or blacks aged 50 and older.


In the United States, treatment of open-angle glaucoma ordinarily begins with prescription eye drops to lower pressure inside the eye. An alternative to medication or when medication is ineffective, trabeculoplasty, laser surgery, is available. Eye surgeons aim a high-intensity light beam at the eye drainage openings to widen them for faster fluid drainage.

If medication and laser surgery both fail, conventional eye surgery by which surgeons create new openings for fluid drainage is the next procedure. Both types of glaucoma surgery, laser and conventional, usually succeed in decreasing pressure but not always low enough, and repeat surgery may be needed.

Many patients fail to continue treatment because they are in no pain and do not notice the gradual loss of vision. They should remember that glaucoma treatment prevents additional eye damage but cannot restore vision already lost.

Closed-angle glaucoma patients must receive treatment as soon as possible to prevent loss of vision. Treatment usually starts with laser surgery to create a new opening in the iris to allow fluid drainage. If done soon enough, this surgery often proves to be a cure, but it may be temporary with the necessity of further surgery or long-term use of eye drops.


The prognosis depends on the form of glaucoma:

  • In open-angle glaucoma, proper treatment greatly reduces the risk of total vision loss. If untreated, however, permanent blindness can be the unfortunate result.
  • In closed-angle glaucoma, with prompt treatment vision in the affected eye may return to a nearly pre-episodic level. If neglected, the affected eye may become blind within days.