Montgomery Eye Physicians

Glaucoma Management

Glaucoma is one of the leading causes of blindness in the U.S., particularly for elderly patients. It is important to know that the loss of sight could frequently be avoided by early detection and treatment.

Anyone having symptoms or risk factors for glaucoma such as diabetes, a family history of glaucoma, or those of African descent should be examined by an eye doctor. Adults with no signs or risk factors should be screened when nearing age 40, as that is the time when early disease process appears. The eye doctor will determine the frequency of follow up examinations based on the findings of the examination.

What is glaucoma?

It is a disease of the optic nerve, the fibrous cable that transmits the images that we see to our brain. When the optic nerve is damaged, blind spots develop. These visual defects can go undetected until there is extensive harm; and by then it is often too late. Destruction of the nerve from the disease process will result in permanent blindness.

The most important risk factors for glaucoma are:

• Age
• Elevated eye pressure
• Family history of glaucoma
• African or Hispanic ancestry
• High degrees of farsightedness or nearsightedness
• Past eye injuries
• Thinner central corneal thickness
• Systemic health problems, including diabetes, migraine headaches, and poor circulation
• Pre-existing thinning of the optic nerve

Diagnosing open angle glaucoma

Early diagnosis and treatment are essential in preventing damage to the optic nerve that could result in blindness. It is important that a baseline of information be established. When evaluating a patient for glaucoma, the eye doctor will look closely at the pressure in the eye, the health of the optic nerve, and the visual field of the patient. The eye doctor will likely inspect the drainage angles of the eyes with the slit lamp while using a special lens called a gonioscope. This technique is called gonioscopy. Other procedures may be requested to complete the evaluation (i.e., optic nerve photographs, visual field test, optical coherence tomography [OCT] of the nerve fiber).

What is intraocular pressure and why is it important?

Glaucoma is one of the leading causes of blindness in the U.S., particularly for elderly patients. It is important to know that the loss of sight could frequently be avoided by early detection and treatment.

Anyone having symptoms or risk factors for glaucoma such as diabetes, a family history of glaucoma, or those of African descent should be examined by an eye doctor. Adults with no signs or risk factors should be screened when nearing age 40, as that is the time when early disease process appears. The eye doctor will determine the frequency of follow up examinations based on the findings of the examination.

What is glaucoma?

It is a disease of the optic nerve, the fibrous cable that transmits the images that we see to our brain. When the optic nerve is damaged, blind spots develop. These visual defects can go undetected until there is extensive harm; and by then it is often too late. Destruction of the nerve from the disease process will result in permanent blindness.

The most important risk factors for glaucoma are:

• Age
• Elevated eye pressure
• Family history of glaucoma
• African or Hispanic ancestry
• High degrees of farsightedness or nearsightedness
• Past eye injuries
• Thinner central corneal thickness
• Systemic health problems, including diabetes, migraine headaches, and poor circulation
• Pre-existing thinning of the optic nerve

Diagnosing open angle glaucoma

Early diagnosis and treatment are essential in preventing damage to the optic nerve that could result in blindness. It is important that a baseline of information be established. When evaluating a patient for glaucoma, the eye doctor will look closely at the pressure in the eye, the health of the optic nerve, and the visual field of the patient. The eye doctor will likely inspect the drainage angles of the eyes with the slit lamp while using a special lens called a gonioscope. This technique is called gonioscopy. Other procedures may be requested to complete the evaluation (i.e., optic nerve photographs, visual field test, optical coherence tomography [OCT] of the nerve fiber).

What is intraocular pressure and why is it important?

Normal pressure in the eye is between 10 and 22 millimeters of mercury. Patients with pressures over 22 are more likely to develop glaucoma. Typically, the higher the intraocular pressure, the greater the potential for having or developing the disease. Statistics demonstrate that a small group of glaucoma patients never develop elevated eye pressure; thus the need for additional testing to look at the health of the optic nerve.

To understand intraocular pressure, we need to know about the structure of the eye. Circulating in the front part of the eye (anterior chamber) is a clear liquid called the aqueous humor. A small amount of this fluid is constantly produced while an equal amount flows out through a tiny drainage system. This allows for a stable intraocular pressure. (This liquid is not part of the tear film on the outer surface of the eye.)

If the drainage angle becomes blocked, excess fluid cannot exit the eye. The pressure inside the eye increases and presses upon the optic nerve, resulting in damage to the nerve.

During the early and middle stages of glaucoma, the pressure within the eye builds up gradually and painlessly (often over a period of months or years). There are no symptoms that a patient would recognize. Without regular eye examinations, the patient would have no idea of the occurring disease process. That is why open angle glaucoma is often referred to as “the silent thief of vision.”

It is important to know that glaucoma screenings, while helpful, are not a sufficient tool to determine a diagnosis of glaucoma. The ONLY way to establish a definitive diagnosis is to have a complete eye exam.

How does intraocular pressure affect the optic nerve?

When the drainage angle becomes blocked, the pressure inside the eye increases. This increase in intraocular pressure can result in damage to the optic nerve.

When examining a patient with glaucoma, the eye doctor will often discover that the optic nerve appears pale. Additionally, the normal indention and cupping of the nerve becomes wider and deeper. These are all signs of disease process. It is critical that treatment be started to reduce pressure and subsequently slow or stop the progression of the glaucoma. This is the primary method used to reduce the likelihood for vision loss.

How does glaucoma affect the visual field?

Typically, vision loss begins as tiny areas of dimness in the side or peripheral vision. Huge portions of the peripheral vision can be lost before the patient recognizes there is a problem. It is not until later in the process of open angle glaucoma that central vision becomes affected. By that point, the glaucoma may be so far advanced that further vision loss cannot be prevented.

When evaluating the patient, the eye doctor will often order a visual field test. The purpose is to evaluate peripheral vision. There are certain patterns to peripheral vision loss that are characteristic of early glaucoma. This test will often allow the eye doctor to make a diagnosis well before the patient develops symptoms. If peripheral vision loss is diagnosed, the eye doctor will probably start either laser treatment or medication to lower the intraocular pressure.

The visual field test can be very monotonous for the patient but is an important tool to detect and manage the glaucoma process.

It is important to note that ALONE, high intraocular pressure, optic nerve damage, or reduction of the visual field will not necessarily form a diagnosis of glaucoma. When two or three are combined, the potential for a positive diagnosis is more probable.

Open angle glaucoma and angle closure glaucoma – how do they differ?

There are two main types of open angle glaucoma – primary and secondary. Primary open angle glaucoma is glaucoma without any known cause. These patients have never experienced injury to their eyes nor have they suffered any event that would cause their intraocular pressure to be abnormally high, resulting in some level of damage. Approximately 85% of all glaucoma cases in the United States are primary open angle glaucoma.

Open angle glaucoma is hereditary. If many people in a family have the disease, the chances of developing glaucoma are higher than if only one or two have the disease. Since nothing is set in stone as to who will or will not develop open angle glaucoma when there is a family history, it is important that all members have routine examinations.

Secondary open angle glaucoma is less common than the primary form of the disease. It is frequently the “secondary” complication of another serious eye disease or injury. The goal is always to stop the progression of the glaucoma as well as the cause. Only 5 to 10 percent of glaucoma cases in the United States are of this type.

As with open angle glaucoma, there are two types of angle closure glaucoma – primary and secondary. Primary angle closure glaucoma has no known cause – but we know that the anatomical structures of these eyes are smaller and more compressed and is more common in people of Asian or Alaskan descent. Secondary angle closure glaucoma is the result of another serious eye disease or injury. Angle closure patients make up between 5 and 10 percent of the glaucoma cases is the United States.

In eyes that are small and farsighted, the iris can be too close to the drainage angle. The iris is actually pushed forward, blocking the channel completely. Since the fluid cannot drain normally, the pressure inside the eye builds up rapidly. The result is an acute closed-angle attack. Symptoms include:

• Blurred vision
• Severe eye pain
• Headdache
• Rainbow colored halos around lights
• Nausea and vomiting

An acute closed-angle attack is considered a true eye emergency. If not treated quickly, blindness can result. Approximately two-thirds of the patients with closed-angle glaucoma develop it slowly and without symptoms prior to having an attack.

What treatments are available for patients with glaucoma?

The BEST way to prevent vision loss is to be diagnosed early and examined regularly, as damage from glaucoma is permanent.

Eye drops, laser treatment, and surgical procedures can be used to lower eye pressure and reduce the potential for further damage. In some cases, oral medications may be prescribed. It is important that the eye doctor and patient work closely together in an effort to halt the progression of the disease. It is critical that patients undergoing treatment for glaucoma use medications as prescribed and keep their eye appointments. It is a lifelong program. Lack of compliance could result in permanent vision loss.

To understand intraocular pressure, we need to know about the structure of the eye. Circulating in the front part of the eye (anterior chamber) is a clear liquid called the aqueous humor. A small amount of this fluid is constantly produced while an equal amount flows out through a tiny drainage system. This allows for a stable intraocular pressure. (This liquid is not part of the tear film on the outer surface of the eye.)

If the drainage angle becomes blocked, excess fluid cannot exit the eye. The pressure inside the eye increases and presses upon the optic nerve, resulting in damage to the nerve.

During the early and middle stages of glaucoma, the pressure within the eye builds up gradually and painlessly (often over a period of months or years). There are no symptoms that a patient would recognize. Without regular eye examinations, the patient would have no idea of the occurring disease process. That is why open angle glaucoma is often referred to as “the silent thief of vision.”

It is important to know that glaucoma screenings, while helpful, are not a sufficient tool to determine a diagnosis of glaucoma. The ONLY way to establish a definitive diagnosis is to have a complete eye exam.

How does intraocular pressure affect the optic nerve?

When the drainage angle becomes blocked, the pressure inside the eye increases. This increase in intraocular pressure can result in damage to the optic nerve.

When examining a patient with glaucoma, the eye doctor will often discover that the optic nerve appears pale. Additionally, the normal indention and cupping of the nerve becomes wider and deeper. These are all signs of disease process. It is critical that treatment be started to reduce pressure and subsequently slow or stop the progression of the glaucoma. This is the primary method used to reduce the likelihood for vision loss.

How does glaucoma affect the visual field?

Typically, vision loss begins as tiny areas of dimness in the side or peripheral vision. Huge portions of the peripheral vision can be lost before the patient recognizes there is a problem. It is not until later in the process of open angle glaucoma that central vision becomes affected. By that point, the glaucoma may be so far advanced that further vision loss cannot be prevented.

When evaluating the patient, the eye doctor will often order a visual field test. The purpose is to evaluate peripheral vision. There are certain patterns to peripheral vision loss that are characteristic of early glaucoma. This test will often allow the eye doctor to make a diagnosis well before the patient develops symptoms. If peripheral vision loss is diagnosed, the eye doctor will probably start either laser treatment or medication to lower the intraocular pressure.

The visual field test can be very monotonous for the patient but is an important tool to detect and manage the glaucoma process.

It is important to note that ALONE, high intraocular pressure, optic nerve damage, or reduction of the visual field will not necessarily form a diagnosis of glaucoma. When two or three are combined, the potential for a positive diagnosis is more probable.

Open angle glaucoma and angle closure glaucoma – how do they differ?

There are two main types of open angle glaucoma – primary and secondary. Primary open angle glaucoma is glaucoma without any known cause. These patients have never experienced injury to their eyes nor have they suffered any event that would cause their intraocular pressure to be abnormally high, resulting in some level of damage. Approximately 85% of all glaucoma cases in the United States are primary open angle glaucoma.

Open angle glaucoma is hereditary. If many people in a family have the disease, the chances of developing glaucoma are higher than if only one or two have the disease. Since nothing is set in stone as to who will or will not develop open angle glaucoma when there is a family history, it is important that all members have routine examinations.

Secondary open angle glaucoma is less common than the primary form of the disease. It is frequently the “secondary” complication of another serious eye disease or injury. The goal is always to stop the progression of the glaucoma as well as the cause. Only 5 to 10 percent of glaucoma cases in the United States are of this type.

As with open angle glaucoma, there are two types of angle closure glaucoma – primary and secondary. Primary angle closure glaucoma has no known cause – but we know that the anatomical structures of these eyes are smaller and more compressed and is more common in people of Asian or Alaskan descent. Secondary angle closure glaucoma is the result of another serious eye disease or injury. Angle closure patients make up between 5 and 10 percent of the glaucoma cases is the United States.

In eyes that are small and farsighted, the iris can be too close to the drainage angle. The iris is actually pushed forward, blocking the channel completely. Since the fluid cannot drain normally, the pressure inside the eye builds up rapidly. The result is an acute closed-angle attack. Symptoms include:

• Blurred vision
• Severe eye pain
• Headdache
• Rainbow colored halos around lights
• Nausea and vomiting

An acute closed-angle attack is considered a true eye emergency. If not treated quickly, blindness can result. Approximately two-thirds of the patients with closed-angle glaucoma develop it slowly and without symptoms prior to having an attack.

What treatments are available for patients with glaucoma?

The BEST way to prevent vision loss is to be diagnosed early and examined regularly, as damage from glaucoma is permanent.

Eye drops, laser treatment, and surgical procedures can be used to lower eye pressure and reduce the potential for further damage. In some cases, oral medications may be prescribed. It is important that the eye doctor and patient work closely together in an effort to halt the progression of the disease. It is critical that patients undergoing treatment for glaucoma use medications as prescribed and keep their eye appointments. It is a lifelong program. Lack of compliance could result in permanent vision loss.