When diagnosing glaucoma, a healthcare provider will typically do a comprehensive eye exam that includes a visual acuity test, visual field test, and dilated eye exam. Although many people are familiar with the common "air puff" test conducted at regular eye exams, most are not aware that this test alone cannot detect glaucoma.
An Introduction to a Glaucoma Diagnosis
Many people may know of the "air puff" test or other tests used to measure eye pressure during an eye examination. However, this test alone cannot detect glaucoma; while elevated eye pressure means that you are at risk for developing glaucoma, it does not necessarily mean that you have it (see Glaucoma and Eye Pressure). A person has glaucoma only if the optic nerve is damaged. If you have increased eye pressure but no damage to the optic nerve, you do not have glaucoma.
Most often, in order to diagnose glaucoma, your doctor will ask you a number of questions (medical history) and perform a comprehensive eye exam.
Eye Exam for Diagnosing Glaucoma
A glaucoma diagnosis is made through a comprehensive eye exam that includes:
•Visual acuity test. This eye chart test measures how well you see at various distances.
•Visual field test. A visual field test measures your side (peripheral) vision. It helps your eye care professional tell if you have lost side vision, a sign of glaucoma.
•Dilated eye exam. For this eye exam, drops are placed in your eyes to widen, or dilate, the pupils. Your eye care professional uses a special magnifying lens to examine your retina and optic nerve for signs of damage and other eye problems. After the exam, your close-up vision may remain blurred for several hours.
•Tonometry. A tonometry is an instrument that measures the pressure inside the eye. Numbing drops may be applied to your eye for this test.
•Pachymetry. For a pachymetry, a numbing drop is applied to your eye. Your eye care professional uses an ultrasonic wave instrument to measure the thickness of your cornea.
Thursday, February 25, 2010
Glaucoma.
Glaucoma is a group of diseases characterized by high pressure within the eye, damage to the optic nerve, and loss of peripheral vision. It is a leading cause of blindness in the United States. Although there is no cure, there are several treatment options, including medication, laser surgery, and traditional surgery, that can control the condition.
An Introduction to Glaucoma
Glaucoma is a group of diseases sharing certain features, commonly including high pressure within the eye (intraocular pressure), damage to the optic nerve, loss of peripheral (side) vision, and possibly blindness.
Nearly 3 million people have glaucoma. Approximately 80,000 Americans become blind each year because of it. The condition causes another 900,000 people to lose partial vision.
However, with early treatment, you may be able to protect your eyes against serious vision loss.
Understanding the Eye
The cornea is the clear outer covering of the eye. Separating it from the iris (the colored part) is the anterior chamber, a space filled and inflated by aqueous humor. This clear fluid (unrelated to the tears which bathe the outside surface of the cornea) starts in the ciliary body just behind the iris. It circulates in the anterior chamber, nourishing the eye's delicate tissue and keeping it from collapsing. To maintain equilibrium, the aqueous humor drains through a porous tissue in the angle in front of the iris, where it meets the cornea, called the trabecular meshwork.
If the aqueous humor cannot drain properly, either because the drainage canals become clogged (as in open angle glaucoma) or because the iris is pushing against the cornea (as in angle closure glaucoma), it backs up, putting pressure on the gel in the vitreous cavity at the center of the eye. Eventually, the building pressure affects the delicate optic nerve at the rear of the eye. Since the optic nerve transmits visual images to the brain, any damage to it reduces vision.
The optic nerve is a bundle of more than one million nerve fibers. It connects the retina to the brain. The retina is the light-sensitive tissue at the back of the eye. A healthy optic nerve is necessary for good vision.
An Introduction to Glaucoma
Glaucoma is a group of diseases sharing certain features, commonly including high pressure within the eye (intraocular pressure), damage to the optic nerve, loss of peripheral (side) vision, and possibly blindness.
Nearly 3 million people have glaucoma. Approximately 80,000 Americans become blind each year because of it. The condition causes another 900,000 people to lose partial vision.
However, with early treatment, you may be able to protect your eyes against serious vision loss.
Understanding the Eye
The cornea is the clear outer covering of the eye. Separating it from the iris (the colored part) is the anterior chamber, a space filled and inflated by aqueous humor. This clear fluid (unrelated to the tears which bathe the outside surface of the cornea) starts in the ciliary body just behind the iris. It circulates in the anterior chamber, nourishing the eye's delicate tissue and keeping it from collapsing. To maintain equilibrium, the aqueous humor drains through a porous tissue in the angle in front of the iris, where it meets the cornea, called the trabecular meshwork.
If the aqueous humor cannot drain properly, either because the drainage canals become clogged (as in open angle glaucoma) or because the iris is pushing against the cornea (as in angle closure glaucoma), it backs up, putting pressure on the gel in the vitreous cavity at the center of the eye. Eventually, the building pressure affects the delicate optic nerve at the rear of the eye. Since the optic nerve transmits visual images to the brain, any damage to it reduces vision.
The optic nerve is a bundle of more than one million nerve fibers. It connects the retina to the brain. The retina is the light-sensitive tissue at the back of the eye. A healthy optic nerve is necessary for good vision.
Glaucoma Medications.
There are many types of medications that can be used for glaucoma, such as beta-blockers, miotics, and adrenergic agonists. These drugs work by either slowing the flow of fluid into the eye or by helping to improve fluid drainage. Medications can effectively stop the progress of the eye condition; however, as the eye develops tolerance to the medicine, it may be necessary to increase dosages as needed.
Medications for Glaucoma: An Overview
Glaucoma medicines are designed to either reduce pressure by slowing the flow of fluid into the eye or help to improve fluid drainage.
While these drugs can effectively stop the progress of glaucoma, increasing dosages may be needed as the eye develops tolerance to the medication.
Medications to treat glaucoma are serious medicine, not to be confused with over-the-counter eye drops for easing common eye irritations. In order to control the disease, glaucoma drugs are taken for life.
There are several different classes of medicine used for glaucoma (available in the form of pills or eye drops). Some of these classes of medications include:
•Beta-blockers
•Miotics
•Adrenergic agonists
•Carbonic anhydrase inhibitors.
Beta-Blockers
The most popular glaucoma medication, Timoptic® (timolol maleate) is a beta-blocker eye drop. Usually taken twice daily, beta-blockers decrease production of aqueous humor.
These medicines may have side effects on the nerves, digestion, vision, skin, respiration, and heart of some individuals. Side effects may include:
•Lowered pulse rate
•Lower blood pressure
•Worsening of asthma
•Fatigue
•Breathing problems.
Miotics
Timoptic has a century-old predecessor, pilocarpine, that requires more frequent use to do its job, increasing drainage of aqueous fluid in both open and closed angle glaucoma. Pilocarpine is a miotic, designed to increase aqueous fluid drainage. Because these glaucoma medications work by making the pupil smaller, they can result in dim vision and may increase the risk of cataracts.
Medications for Glaucoma: An Overview
Glaucoma medicines are designed to either reduce pressure by slowing the flow of fluid into the eye or help to improve fluid drainage.
While these drugs can effectively stop the progress of glaucoma, increasing dosages may be needed as the eye develops tolerance to the medication.
Medications to treat glaucoma are serious medicine, not to be confused with over-the-counter eye drops for easing common eye irritations. In order to control the disease, glaucoma drugs are taken for life.
There are several different classes of medicine used for glaucoma (available in the form of pills or eye drops). Some of these classes of medications include:
•Beta-blockers
•Miotics
•Adrenergic agonists
•Carbonic anhydrase inhibitors.
Beta-Blockers
The most popular glaucoma medication, Timoptic® (timolol maleate) is a beta-blocker eye drop. Usually taken twice daily, beta-blockers decrease production of aqueous humor.
These medicines may have side effects on the nerves, digestion, vision, skin, respiration, and heart of some individuals. Side effects may include:
•Lowered pulse rate
•Lower blood pressure
•Worsening of asthma
•Fatigue
•Breathing problems.
Miotics
Timoptic has a century-old predecessor, pilocarpine, that requires more frequent use to do its job, increasing drainage of aqueous fluid in both open and closed angle glaucoma. Pilocarpine is a miotic, designed to increase aqueous fluid drainage. Because these glaucoma medications work by making the pupil smaller, they can result in dim vision and may increase the risk of cataracts.
Acute Glaucoma.
Acute glaucoma is a less common (but very serious) form of glaucoma. It is characterized by increased eye pressure, intense pain, and rapid damage to the optic nerve. Without immediate treatment during an attack, this condition can quickly lead to vision loss. People who have farsightedness, diabetes, or a family history of glaucoma are at a higher risk of developing it.
What Is Acute Glaucoma?
Acute glaucoma is one of the many different glaucoma types (see Types of Glaucoma). It is much less common than chronic glaucoma (also known as open angle glaucoma). However, acute glaucoma is very serious because it can cause rapid damage and loss of vision; it can also erupt in violent attacks and intense pain, rather than emerging subtly.
This condition occurs in less than 10 percent of glaucoma cases.
Other names for acute glaucoma include:
•Closed angle glaucoma
•Angle closure glaucoma
•Narrow angle glaucoma.
How Acute Glaucoma Affects the Eye
The cornea is the clear outer covering of the eye. Separating it from the iris (the colored part) is the anterior chamber, a space filled and inflated by aqueous humor. This clear fluid (unrelated to the tears that bathe the outside surface of the cornea) starts in the ciliary body just behind the iris. It circulates in the anterior chamber, nourishing the eye's delicate tissue and keeping it from collapsing.
To maintain equilibrium, the aqueous humor drains through a porous tissue in the angle in front of the iris, where it meets the cornea, called the trabecular meshwork.
If the aqueous humor cannot drain properly because the iris is pushing against the cornea (as in acute glaucoma), it backs up, putting pressure on the gel in the vitreous cavity at the center of the eye. Eventually, the building pressure affects the delicate optic nerve at the rear of the eye. Since the optic nerve transmits visual images to the brain, any damage to it reduces vision.
The optic nerve is a bundle of more than one million nerve fibers. It connects the retina to the brain. The retina is the light-sensitive tissue at the back of the eye. A healthy optic nerve is necessary for good vision.
What Is Acute Glaucoma?
Acute glaucoma is one of the many different glaucoma types (see Types of Glaucoma). It is much less common than chronic glaucoma (also known as open angle glaucoma). However, acute glaucoma is very serious because it can cause rapid damage and loss of vision; it can also erupt in violent attacks and intense pain, rather than emerging subtly.
This condition occurs in less than 10 percent of glaucoma cases.
Other names for acute glaucoma include:
•Closed angle glaucoma
•Angle closure glaucoma
•Narrow angle glaucoma.
How Acute Glaucoma Affects the Eye
The cornea is the clear outer covering of the eye. Separating it from the iris (the colored part) is the anterior chamber, a space filled and inflated by aqueous humor. This clear fluid (unrelated to the tears that bathe the outside surface of the cornea) starts in the ciliary body just behind the iris. It circulates in the anterior chamber, nourishing the eye's delicate tissue and keeping it from collapsing.
To maintain equilibrium, the aqueous humor drains through a porous tissue in the angle in front of the iris, where it meets the cornea, called the trabecular meshwork.
If the aqueous humor cannot drain properly because the iris is pushing against the cornea (as in acute glaucoma), it backs up, putting pressure on the gel in the vitreous cavity at the center of the eye. Eventually, the building pressure affects the delicate optic nerve at the rear of the eye. Since the optic nerve transmits visual images to the brain, any damage to it reduces vision.
The optic nerve is a bundle of more than one million nerve fibers. It connects the retina to the brain. The retina is the light-sensitive tissue at the back of the eye. A healthy optic nerve is necessary for good vision.
Glaucoma Research.
Doctors and scientists all over the country are conducting research on glaucoma. These studies are designed to answer important questions and to find out whether new approaches are safe and effective. This research has already led to many advances, and researchers continue to search for more effective methods for dealing with glaucoma.
Ongoing glaucoma research aims to simplify medication demands while reducing side effects. For instance, the nuisance of taking preventive medications several times a day discourages some people from protecting themselves fully. Work is under way to perfect a once-a-week eye preparation and once-a-day eyedrops to ease the use of topical glaucoma medicines. Already, dispenser tips that measure more consistent doses of eyedrops are improving their use.
In addition, a large amount of research is being done to learn what causes glaucoma and to improve diagnosis and treatment. For instance, a number of glaucoma research studies are designed to find out what causes fluid pressure to increase in the eye. By learning more about this process, doctors may be able to find the exact cause of glaucoma and better understand how to prevent and treat it.
Research is also being conducted to learn more about who is likely to get glaucoma, when to treat people with increased pressure, and which treatment method to use first.
In order for glaucoma research to be conducted, volunteers are needed. People who join research studies have the first chance to benefit from treatments that have shown promise in earlier research. They also make an important contribution to medical science by helping doctors learn more about glaucoma. Although research trials may pose some risks, researchers take careful steps to protect their patients
Ongoing glaucoma research aims to simplify medication demands while reducing side effects. For instance, the nuisance of taking preventive medications several times a day discourages some people from protecting themselves fully. Work is under way to perfect a once-a-week eye preparation and once-a-day eyedrops to ease the use of topical glaucoma medicines. Already, dispenser tips that measure more consistent doses of eyedrops are improving their use.
In addition, a large amount of research is being done to learn what causes glaucoma and to improve diagnosis and treatment. For instance, a number of glaucoma research studies are designed to find out what causes fluid pressure to increase in the eye. By learning more about this process, doctors may be able to find the exact cause of glaucoma and better understand how to prevent and treat it.
Research is also being conducted to learn more about who is likely to get glaucoma, when to treat people with increased pressure, and which treatment method to use first.
In order for glaucoma research to be conducted, volunteers are needed. People who join research studies have the first chance to benefit from treatments that have shown promise in earlier research. They also make an important contribution to medical science by helping doctors learn more about glaucoma. Although research trials may pose some risks, researchers take careful steps to protect their patients
Glaucoma SymptomsThe type of glaucoma.
Glaucoma SymptomsThe type of glaucoma a person has will affect the symptoms of glaucoma that person experiences. However, all symptoms inhibit vision in one way or another. Common signs and symptoms of the condition include cloudy eyes, sensitivity to light, and loss of side (peripheral) vision.
Open angle glaucoma typically affects people over the age of 50. At first, a person with open angle glaucoma has no symptoms; the condition causes no pain, and vision stays normal.
However, as the condition progresses, a person with open angle glaucoma may notice a gradual failure of side vision (objects in front may be clear, but objects to the side may be missed). This may seem similar to looking into a tunnel.
If left untreated, glaucoma can begin to cause a loss of straight-ahead vision and eventually lead to irreversible blindness.
Primary angle-closure glaucoma (also known as acute glaucoma) is another form of glaucoma (see Types of Glaucoma). Unlike symptoms seen with open angle glaucoma, symptoms with this type begin suddenly and violently.
In angle closure glaucoma, the fluid at the front of the eye cannot reach the angle and leave the eye. The angle gets blocked by part of the iris. People with this type of glaucoma have a sudden increase in eye pressure.
As a result, signs and symptoms of angle closure glaucoma include:
•Severe pain
•Nausea
•Redness of the eye
•Blurred vision.
If you have these symptoms, you need to seek treatment immediately. This is a medical emergency. If your doctor is unavailable, go to the nearest hospital or clinic.
Open angle glaucoma typically affects people over the age of 50. At first, a person with open angle glaucoma has no symptoms; the condition causes no pain, and vision stays normal.
However, as the condition progresses, a person with open angle glaucoma may notice a gradual failure of side vision (objects in front may be clear, but objects to the side may be missed). This may seem similar to looking into a tunnel.
If left untreated, glaucoma can begin to cause a loss of straight-ahead vision and eventually lead to irreversible blindness.
Primary angle-closure glaucoma (also known as acute glaucoma) is another form of glaucoma (see Types of Glaucoma). Unlike symptoms seen with open angle glaucoma, symptoms with this type begin suddenly and violently.
In angle closure glaucoma, the fluid at the front of the eye cannot reach the angle and leave the eye. The angle gets blocked by part of the iris. People with this type of glaucoma have a sudden increase in eye pressure.
As a result, signs and symptoms of angle closure glaucoma include:
•Severe pain
•Nausea
•Redness of the eye
•Blurred vision.
If you have these symptoms, you need to seek treatment immediately. This is a medical emergency. If your doctor is unavailable, go to the nearest hospital or clinic.
Everyone should be concerned about glaucoma?
Everyone should be concerned about glaucoma and its effects. It is important for each of us, from infants to senior citizens, to have our eyes checked regularly, because early detection and treatment of glaucoma are the only way to prevent vision impairment and blindness. There are a few factors related to this disease which tend to put some people at greater risk:
•People over the age of 40.
While glaucoma can develop in younger patients, it occurs more frequently as we get older. •People who have a family history of glaucoma.
Glaucoma appears to run in families. The tendency for developing glaucoma may be inherited. However, just because someone in your family has glaucoma does not mean that you will necessarily develop the disease. •People with abnormally high intraocular pressure (IOP).
High IOP is the most important risk factor for glaucomatous damage. •People of African-American, Hispanic, or Asian-American descent.
African-Americans and Hispanics have a greater tendency for developing primary open-angle glaucoma than do people of other races. Asian-Americans are more prone to develop angle-closure glaucoma and normal-tension glaucoma.
•People who have: ◦Diabetes ◦Myopia (nearsightedness) ◦Regular, long-term steroid/cortisone use ◦A previous eye injury ◦A family history of glaucoma
◦Extremely high or low blood pressure
Everyone under 40 should have a comprehensive eye examination every three to four years. Individuals under 40 with one of the above risk factors should get tested every one and a half to two years. Everyone 40 years or older should have a comprehensive eye examination every one and a half to two years. If you are 40 and have an additional risk factor listed above, get tested annually. Anyone with high risk factors should be tested every year or two after 35.
•People over the age of 40.
While glaucoma can develop in younger patients, it occurs more frequently as we get older. •People who have a family history of glaucoma.
Glaucoma appears to run in families. The tendency for developing glaucoma may be inherited. However, just because someone in your family has glaucoma does not mean that you will necessarily develop the disease. •People with abnormally high intraocular pressure (IOP).
High IOP is the most important risk factor for glaucomatous damage. •People of African-American, Hispanic, or Asian-American descent.
African-Americans and Hispanics have a greater tendency for developing primary open-angle glaucoma than do people of other races. Asian-Americans are more prone to develop angle-closure glaucoma and normal-tension glaucoma.
•People who have: ◦Diabetes ◦Myopia (nearsightedness) ◦Regular, long-term steroid/cortisone use ◦A previous eye injury ◦A family history of glaucoma
◦Extremely high or low blood pressure
Everyone under 40 should have a comprehensive eye examination every three to four years. Individuals under 40 with one of the above risk factors should get tested every one and a half to two years. Everyone 40 years or older should have a comprehensive eye examination every one and a half to two years. If you are 40 and have an additional risk factor listed above, get tested annually. Anyone with high risk factors should be tested every year or two after 35.
Glaucoma can be treated with ....
......eye drops, pills, laser surgery, traditional surgery or a combination of these methods. The goal of any treatment is to prevent loss of vision, as vision loss from glaucoma is irreversible. The good news is that glaucoma can be managed if detected early, and that with medical and/or surgical treatment, most people with glaucoma will not lose their sight.
Taking medications regularly, as prescribed, is crucial to preventing vision-threatening damage. That is why it is important for you to discuss side effects with your doctor. While every drug has some potential side effects, it is important to note that many patients experience no side effects at all. You and your doctor need to work as a team in the battle against glaucoma. Your doctor has many options. They include:
Eye Drops
It is important to take your medications regularly and exactly as prescribed if you are to control your eye pressure. Since eye drops are absorbed into the bloodstream, tell your doctor about all medications you are currently taking. Ask your doctor and/or pharmacist if the medications you are taking together are safe. Some drugs can be dangerous when mixed with other medications. To minimize absorption into the bloodstream and maximize the amount of drug absorbed in the eye, close your eye for one to two minutes after administering the drops and press your index finger lightly against the inferior nasal corner of your eyelid to close the tear duct which drains into the nose. While almost all eye drops may cause an uncomfortable burning or stinging sensation at first, the discomfort should last for only a few seconds.
Eye Drops
Sometimes, when eye drops don't sufficiently control IOP, pills may be prescribed in addition to drops. These pills, which have more systemic side effects than drops, also serve to turn down the eye's faucet and lessen the production of fluid. These medications are usually taken from two to four times daily. It is important to share this information with all your other doctors so they can prescribe medications for you which will not cause potentially dangerous interactions.
Taking medications regularly, as prescribed, is crucial to preventing vision-threatening damage. That is why it is important for you to discuss side effects with your doctor. While every drug has some potential side effects, it is important to note that many patients experience no side effects at all. You and your doctor need to work as a team in the battle against glaucoma. Your doctor has many options. They include:
Eye Drops
It is important to take your medications regularly and exactly as prescribed if you are to control your eye pressure. Since eye drops are absorbed into the bloodstream, tell your doctor about all medications you are currently taking. Ask your doctor and/or pharmacist if the medications you are taking together are safe. Some drugs can be dangerous when mixed with other medications. To minimize absorption into the bloodstream and maximize the amount of drug absorbed in the eye, close your eye for one to two minutes after administering the drops and press your index finger lightly against the inferior nasal corner of your eyelid to close the tear duct which drains into the nose. While almost all eye drops may cause an uncomfortable burning or stinging sensation at first, the discomfort should last for only a few seconds.
Eye Drops
Sometimes, when eye drops don't sufficiently control IOP, pills may be prescribed in addition to drops. These pills, which have more systemic side effects than drops, also serve to turn down the eye's faucet and lessen the production of fluid. These medications are usually taken from two to four times daily. It is important to share this information with all your other doctors so they can prescribe medications for you which will not cause potentially dangerous interactions.
Diagnosing glaucoma.
Your eye doctor has a variety of diagnostic tools which aid in determining whether or not you have glaucoma -- even before you have any symptoms. Let us explore these tools and what they do.
The Tonometer
The tonometer measures the pressure in your eye. Your doctor places a numbing eye drop in your eye. Then you sit at a slit-lamp, resting your chin and forehead on a support that keeps your head steady. The lamp, which lets your doctor see a magnified view of your eye, is moved forward until the tonometer, a plastic prism, barely touches the cornea to measure your IOP. The test is quick, easy and painless.
The Pachymeter
The pachymeter measures central corneal thickness (CCT). Like the tonometer, your doctor will first anesthetize your eyes. Then a small probe will be placed perpendicular to the central cornea.
CCT is an important measure and helps your doctor interpret your IOP levels. Some people with thin central corneal thickness will have pressures that are actually higher than when measured by tonometry. Likewise, those with thick CCT will have a true IOP that is lower than that measured. Measuring your central corneal thickness is also important since recent studies have found that thin CCT is a strong predictor of developing glaucoma in patients with high IOP.
The Tonometer
The tonometer measures the pressure in your eye. Your doctor places a numbing eye drop in your eye. Then you sit at a slit-lamp, resting your chin and forehead on a support that keeps your head steady. The lamp, which lets your doctor see a magnified view of your eye, is moved forward until the tonometer, a plastic prism, barely touches the cornea to measure your IOP. The test is quick, easy and painless.
The Pachymeter
The pachymeter measures central corneal thickness (CCT). Like the tonometer, your doctor will first anesthetize your eyes. Then a small probe will be placed perpendicular to the central cornea.
CCT is an important measure and helps your doctor interpret your IOP levels. Some people with thin central corneal thickness will have pressures that are actually higher than when measured by tonometry. Likewise, those with thick CCT will have a true IOP that is lower than that measured. Measuring your central corneal thickness is also important since recent studies have found that thin CCT is a strong predictor of developing glaucoma in patients with high IOP.
Childhood glaucoma .....
.....is an unusual eye disease and significant cause of childhood blindness. It is caused by disease related abnormal increase in intraocular pressure. The multiple potential causes fall into one of two categories and may be primary or secondary to some other disease process. Primary congenital glaucoma results from abnormal development of the ocular drainage system. It occurs in about 1 out of 10,000 births in the United States and is the most common form of glaucoma in infants. Secondary glaucomas result from disorders of the body or eye and may or may not be genetic. Both types may be associated with other medical diseases.
Ten percent of primary congenital glaucomas are present at birth, and 80 percent are diagnosed during the first year of life. The pediatrician or family first notice eye signs of glaucoma including clouding and/or enlargement of the cornea. The elevated intraocular pressure (IOP) can cause the eyeball itself to enlarge and injury to the cornea. Important early symptoms of glaucoma in infants and children are poor vision, light sensitivity, tearing, and blinking.
Pediatric glaucoma is treated differently than adult glaucoma. Most patients require surgery and this is typically performed early. The aim of pediatric glaucoma surgery is to reduce IOP either by increasing the outflow of fluid from the eye or decrease the production of fluid within the eye. One operation for pediatric glaucoma is goniotomy. Its rate of success is associated with the age of the child at the time of diagnosis, the type and severity of the glaucoma, and the surgery technique. Other surgical options are trabeculectomy and glaucoma drainage tubes.
Approximately 80-90 percent of babies who receive prompt surgical treatment, long-term care, and monitoring of their visual development will do well, and may have normal or nearly normal vision for their lifetime. Sadly, primary congenital glaucoma results in blindness in 2 to 15 percent of childhood patients. When childhood glaucoma is not recognized and treated promptly more permanent visual loss will result.
Ten percent of primary congenital glaucomas are present at birth, and 80 percent are diagnosed during the first year of life. The pediatrician or family first notice eye signs of glaucoma including clouding and/or enlargement of the cornea. The elevated intraocular pressure (IOP) can cause the eyeball itself to enlarge and injury to the cornea. Important early symptoms of glaucoma in infants and children are poor vision, light sensitivity, tearing, and blinking.
Pediatric glaucoma is treated differently than adult glaucoma. Most patients require surgery and this is typically performed early. The aim of pediatric glaucoma surgery is to reduce IOP either by increasing the outflow of fluid from the eye or decrease the production of fluid within the eye. One operation for pediatric glaucoma is goniotomy. Its rate of success is associated with the age of the child at the time of diagnosis, the type and severity of the glaucoma, and the surgery technique. Other surgical options are trabeculectomy and glaucoma drainage tubes.
Approximately 80-90 percent of babies who receive prompt surgical treatment, long-term care, and monitoring of their visual development will do well, and may have normal or nearly normal vision for their lifetime. Sadly, primary congenital glaucoma results in blindness in 2 to 15 percent of childhood patients. When childhood glaucoma is not recognized and treated promptly more permanent visual loss will result.
Wednesday, February 24, 2010
Pediatric Glaucoma.
The pediatric glaucomas consist of congenital glaucoma (present at birth), infantile glaucoma (appears during the first three years), juvenile glaucoma (age three through the teenage or young adult years), and all the secondary glaucomas occurring in the pediatric age group.
Congenital glaucoma is present at birth and most cases are diagnosed during the first year of life. Sometimes symptoms are not recognized until later in infancy or early childhood.
The range of treatment is very different from that for adult glaucoma. It is very important to catch pediatric glaucoma early in order to prevent blindness.
Congenital glaucoma is present at birth and most cases are diagnosed during the first year of life. Sometimes symptoms are not recognized until later in infancy or early childhood.
The range of treatment is very different from that for adult glaucoma. It is very important to catch pediatric glaucoma early in order to prevent blindness.
Types of Glaucoma.
Secondary GlaucomaGlaucoma can occur as the result of an eye injury, inflammation, tumor or in advanced cases of cataract or diabetes. It can also be caused by certain drugs such as steroids. This form of glaucoma may be mild or severe. The type of treatment will depend on whether it is open angle or angle closure glaucoma.
Pseudoexfoliative Glaucoma
This form of secondary open angle glaucoma occurs when a flaky, dandruff-like material peels off the outer layer of the lens within the eye. The material collects in the angle between the cornea and iris and can clog the drainage system of the eye, causing eye pressure to rise.
Pseudoexfoliative Glaucoma is common in those of Scandinavian descent. Treatment usually includes medications or surgery.
Pigmentary GlaucomaA form of secondary open angle glaucoma, this occurs when the pigment granules in the back of the iris (the colored part of the eye) break into the clear fluid produced inside the eye. These tiny pigment granules flow toward the drainage canals in the eye and slowly clog them, causing eye pressure to rise. Treatment usually includes medications or surgery.
Pseudoexfoliative Glaucoma
This form of secondary open angle glaucoma occurs when a flaky, dandruff-like material peels off the outer layer of the lens within the eye. The material collects in the angle between the cornea and iris and can clog the drainage system of the eye, causing eye pressure to rise.
Pseudoexfoliative Glaucoma is common in those of Scandinavian descent. Treatment usually includes medications or surgery.
Pigmentary GlaucomaA form of secondary open angle glaucoma, this occurs when the pigment granules in the back of the iris (the colored part of the eye) break into the clear fluid produced inside the eye. These tiny pigment granules flow toward the drainage canals in the eye and slowly clog them, causing eye pressure to rise. Treatment usually includes medications or surgery.
Normal Tension Glaucoma (NTG).
Normal tension glaucoma is also known as low-tension glaucoma or normal pressure glaucoma. In this type of glaucoma, the optic nerve is damaged even though intraocular pressure (IOP) is not very high. Doctors do not know why some people’s optic nerves suffer damage even though pressure levels are in the “normal” range (between 12-22 mm Hg).
Those at higher risk for this form of glaucoma are people with a family history of normal tension glaucoma, people of Japanese ancestry, and people with a history of systemic heart disease, such as irregular heart rhythm. Normal tension glaucoma is usually detected after an examination of the optic nerve.
The Glaucoma Research Foundation sponsored a collaborative international study to help determine the best treatment for this type of glaucoma. The study concluded that eye drops used to lower intraocular pressure were effective even in cases of normal tension glaucoma. Currently, most doctors treat normal tension glaucoma by keeping normal eye pressures as low as possible with medicines, laser surgery, or filtering surgery.
Those at higher risk for this form of glaucoma are people with a family history of normal tension glaucoma, people of Japanese ancestry, and people with a history of systemic heart disease, such as irregular heart rhythm. Normal tension glaucoma is usually detected after an examination of the optic nerve.
The Glaucoma Research Foundation sponsored a collaborative international study to help determine the best treatment for this type of glaucoma. The study concluded that eye drops used to lower intraocular pressure were effective even in cases of normal tension glaucoma. Currently, most doctors treat normal tension glaucoma by keeping normal eye pressures as low as possible with medicines, laser surgery, or filtering surgery.
Glaucoma Laser Surgery .
If you’ve been diagnosed with glaucoma and have been been thinking about getting laser surgery as a treatment and are wondering what the procedure for glaucoma laser surgery is, I’ll explain in this article how it’s done.
Laser surgery is used to help control glaucoma. If you’re using glaucoma medicines now, either eye drops or oral medications, you may be suffering from the side effects of these drugs. Some of the side effects you may not be aware of. You may want to get off these medicines but are concerned about the buildup of pressure in your eyes.
Surgical Procedures
When medications do not achieve the desired results, or have intolerable side effects, your ophthalmologist may suggest surgery.
Laser SurgeryLaser surgery has become increasingly popular as an intermediate step between drugs and traditional surgery though the long-term success rates are variable. The most common type performed for open-angle glaucoma is called trabeculoplasty. This procedure takes between 10 and 15 minutes, is painless, and can be performed in either a doctor's office or an outpatient facility. The laser beam (a high energy light beam) is focused upon the eye's drain. Contrary to what many people think, the laser does not bum a hole through the eye. Instead, the eye's drainage system is changed in very subtle ways so that aqueous fluid is able to pass more easily out of the drain, thus lowering IOP.
You may go home and resume your normal activities following surgery. Your doctor will likely check your IOP one to two hours following laser surgery. After this procedure, many patients respond well enough to be able to avoid or delay surgery. While it may take a few weeks to see the full pressure-lowering effect of this procedure, during which time you may have to continue taking your medications, many patients are eventually able to discontinue some of their medications. This, however, is not true in all cases. Your doctor is the best judge of determining whether or not you will still need medication. Complications from laser are minimal, which is why this procedure has become increasingly popular and some centers are recommending the use of laser before drops in some patients.
Argon Laser Trabeculoplasty (ALT) -- for open-angle glaucoma
The laser treats the trabecular meshwork of the eye, increasing the drainage outflow, thereby lowering the IOP. In many cases, medication will still be needed. Usually, half the trabecular meshwork is treated first. If necessary, the other half can be treated as a separate procedure. This method decreases the risk of increased pressure following surgery. Argon laser trabeculoplasty has successfully lowered eye pressure in up to 75 percent of patients treated. This type of laser can be performed only two to three times in each eye over a lifetime.
Selective Laser Trabeculoplasty (SLT) -- for open-angle glaucomaSLT is a newer laser that uses very low levels of energy. It is termed "selective" since it leaves portions of the trabecular meshwork intact. For this reason, it is believed that SLT, unlike other types of laser surgery, may be safely repeated. Some authors have reported that a second repeat application of SLT or SLT after prior ALT is effective at lowering IOP.
Laser Peripheral Iridotomy (LPI) -- for angle-closure glaucomaThis procedure is used to make an opening through the iris, allowing aqueous fluid to flow from behind the iris directly to the anterior chamber of the eye. This allows the fluid to bypass its normal route. LPI is the preferred method for managing a wide variety of angle-closure glaucomas that have some degree of pupillary blockage. This laser is most often used to treat an anatomically narrow angle and prevent angle-closure glaucoma attacks.
CycloablationTwo laser procedures for open-angle glaucoma involve reducing the amount of aqueous humor in the eye by destroying part of the ciliary body, which produces the fluid. These treatments are usually reserved for use in eyes that either have elevated IOP after having failed other more traditional treatments, including filtering surgery, or those in which filtering surgery is not possible or advisable due to the shape or other features of the eye. Transscleral cyclophotocoagulation uses a laser to direct energy through the outer sclera of the eye to reach and destroy portions of the ciliary processes, without causing damage to the overlying tissues. With endoscopic cyclophotocoagulation (ECP), the instrument is placed inside the eye through a surgical incision, so that the laser energy is applied directly to the ciliary body tissue.
Traditional Surgery
Trabeculectomy
When medications and laser therapies do not adequately lower eye pressure, doctors may recommend conventional surgery. The most common of these operations is called a trabeculectomy, which is used in both open-angle and closed-angle glaucomas. In this procedure, the surgeon creates a passage in the sclera (the white part of the eye) for draining excess eye fluid. A flap is created that allows fluid to escape, but which does not deflate the eyeball. A small bubble of fluid called a "bleb" often forms over the opening on the surface of the eye, which is a sign that fluid is draining out into the space between the sclera and conjunctiva. Occasionally, the surgically created drainage hole begins to close and the IOP rises again. This happens because the body tries to heal the new opening, as if it was an injury. Many surgeons perform trabeculectomy with an anti-fibrotic agent that is placed on the eye during surgery and reduces such scarring during the healing period. The most common anti-fibrotic agent is Mitomycin-C. Another is 5-Fluorouracil, or 5-FU.
About 50 percent of patients no longer require glaucoma medications after surgery for a significant length of time. Thirty-five to 40 percent of those who still need medication have better control of their IOP. A trabeculectomy is usually an outpatient procedure. The number of post-operative visits to the doctor varies, and some activities, such as driving, reading, bending and heavy lifting must be limited for two to four weeks after surgery.
Drainage Implant SurgerySeveral different devices have been developed to aid the drainage of aqueous humor out of the anterior chamber and lower IOP. All of these drainage devices share a similar design which consists of a small silicone tube that extends into the anterior chamber of the eye. The tube is connected to one or more plates, which are sutured to the surface of the eye, usually not visible. Fluid is collected on the plate and then absorbed by the tissues in the eye. This type of surgery is thought to lower IOP less than trabeculectomy but is preferred in patients whose IOP cannot be controlled with traditional surgery or who have previous scarring.
Nonpenetrating SurgeryNewer nonpenetrating glaucoma surgery, which does not enter the anterior chamber of the eye, shows great promise in minimizing postoperative complications and lowering the risk for infection. However, such surgery often requires a greater surgical acument and generally does not lower IOP as much as trabeculectomy. Furthermore, long term studies are needed to assess these procedures and to determine their role in the clinical management of glaucoma patients.
Some Promising Surgical Alternatives The ExPress mini glaucoma shunt is a stainless steel device that is inserted into the anterior chamber of the eye and placed under a scleral flap. It lowers IOP by diverting aqueous humor from the anterior chamber. The ExPress offers the glaucoma surgeon an alternative to either repeating a trabeculectomy or placing a more extensive silicone tube shunt in those patients whose IOP is higher than the optic nerve can tolerate.
The Trabectome is a new probe-like device that is inserted into the anterior chamber through the cornea. The procedure uses a small probe that opens the eye's drainage system through a tiny incision and delivers thermal energy to the trabecular meshwork, reducing resistance to outflow of aqueous humor and, as a result, lowering IOP.
Canaloplasty, a recent advancement in non-penetrating surgery, is designed to improve the aqueous circulation through the trabecular outflow process, thereby reducing IOP. Unlike traditional trabeculectomy, which creates a small hole in the eye to allow fluid to drain out, canaloplasty has been compared to an ocular version of angioplasty, in which the physician uses an extremely fine catheter to clear the drainage canal.
Glaucoma eye drops do have significant side effects and it’s best if you can stop taking them provided you have an alternative and that alternative may be laser surgery. Sometimes glaucoma medications don’t work.
Simply- glaucoma is an eye disease of which there are two basic kinds – primary open angle and acute angle-closure.
There is a clear fluid that flows though the passages of your eye. Sometimes these passages get blocked and the fluid will build up in the eye and cause too much pressure. This pressure can cause damage to the optic nerve and a loss of vision. The result is glaucoma.
Laser surgery uses a tiny but powerful light beam to help drain the fluid from your eye easier. The eye surgeon will make holes or use it to shrink the clogged areas in your eye. This surgery can help you decrease your eye pressure. The surgery may be done on one or both eye. It can affect one eye only.
The surgery is done in your doctors’ office or in a clinic. You should be able to see just fine after surgery except you may feel some grittiness in your eye or eyes. Your eye or eyes may be swollen too. But these symptoms will go away in a day or two. You may have some sensitivity to light and some blurred vision for three weeks or so while your eyes heal. You would still take your eye drops or oral medications during this time period.
Now this is the basic procedure is for glaucoma laser surgery. Your ophthalmologist can fill you in more fully as it applies to your individual eye problem.
It’s important to note that any lost vision won’t return. This surgery is meant to prevent future loss of vision and help you avoid taking lifetime medications that may be harmful to your body. Laser surgery may not be appropriate for all types of glaucoma but your eye surgeon or ophthalmologist will help determine that. In any case glaucoma laser surgery is a consideration and want to avoid eye drops and seek a better solution.
Laser surgery is used to help control glaucoma. If you’re using glaucoma medicines now, either eye drops or oral medications, you may be suffering from the side effects of these drugs. Some of the side effects you may not be aware of. You may want to get off these medicines but are concerned about the buildup of pressure in your eyes.
Surgical Procedures
When medications do not achieve the desired results, or have intolerable side effects, your ophthalmologist may suggest surgery.
Laser SurgeryLaser surgery has become increasingly popular as an intermediate step between drugs and traditional surgery though the long-term success rates are variable. The most common type performed for open-angle glaucoma is called trabeculoplasty. This procedure takes between 10 and 15 minutes, is painless, and can be performed in either a doctor's office or an outpatient facility. The laser beam (a high energy light beam) is focused upon the eye's drain. Contrary to what many people think, the laser does not bum a hole through the eye. Instead, the eye's drainage system is changed in very subtle ways so that aqueous fluid is able to pass more easily out of the drain, thus lowering IOP.
You may go home and resume your normal activities following surgery. Your doctor will likely check your IOP one to two hours following laser surgery. After this procedure, many patients respond well enough to be able to avoid or delay surgery. While it may take a few weeks to see the full pressure-lowering effect of this procedure, during which time you may have to continue taking your medications, many patients are eventually able to discontinue some of their medications. This, however, is not true in all cases. Your doctor is the best judge of determining whether or not you will still need medication. Complications from laser are minimal, which is why this procedure has become increasingly popular and some centers are recommending the use of laser before drops in some patients.
Argon Laser Trabeculoplasty (ALT) -- for open-angle glaucoma
The laser treats the trabecular meshwork of the eye, increasing the drainage outflow, thereby lowering the IOP. In many cases, medication will still be needed. Usually, half the trabecular meshwork is treated first. If necessary, the other half can be treated as a separate procedure. This method decreases the risk of increased pressure following surgery. Argon laser trabeculoplasty has successfully lowered eye pressure in up to 75 percent of patients treated. This type of laser can be performed only two to three times in each eye over a lifetime.
Selective Laser Trabeculoplasty (SLT) -- for open-angle glaucomaSLT is a newer laser that uses very low levels of energy. It is termed "selective" since it leaves portions of the trabecular meshwork intact. For this reason, it is believed that SLT, unlike other types of laser surgery, may be safely repeated. Some authors have reported that a second repeat application of SLT or SLT after prior ALT is effective at lowering IOP.
Laser Peripheral Iridotomy (LPI) -- for angle-closure glaucomaThis procedure is used to make an opening through the iris, allowing aqueous fluid to flow from behind the iris directly to the anterior chamber of the eye. This allows the fluid to bypass its normal route. LPI is the preferred method for managing a wide variety of angle-closure glaucomas that have some degree of pupillary blockage. This laser is most often used to treat an anatomically narrow angle and prevent angle-closure glaucoma attacks.
CycloablationTwo laser procedures for open-angle glaucoma involve reducing the amount of aqueous humor in the eye by destroying part of the ciliary body, which produces the fluid. These treatments are usually reserved for use in eyes that either have elevated IOP after having failed other more traditional treatments, including filtering surgery, or those in which filtering surgery is not possible or advisable due to the shape or other features of the eye. Transscleral cyclophotocoagulation uses a laser to direct energy through the outer sclera of the eye to reach and destroy portions of the ciliary processes, without causing damage to the overlying tissues. With endoscopic cyclophotocoagulation (ECP), the instrument is placed inside the eye through a surgical incision, so that the laser energy is applied directly to the ciliary body tissue.
Traditional Surgery
Trabeculectomy
When medications and laser therapies do not adequately lower eye pressure, doctors may recommend conventional surgery. The most common of these operations is called a trabeculectomy, which is used in both open-angle and closed-angle glaucomas. In this procedure, the surgeon creates a passage in the sclera (the white part of the eye) for draining excess eye fluid. A flap is created that allows fluid to escape, but which does not deflate the eyeball. A small bubble of fluid called a "bleb" often forms over the opening on the surface of the eye, which is a sign that fluid is draining out into the space between the sclera and conjunctiva. Occasionally, the surgically created drainage hole begins to close and the IOP rises again. This happens because the body tries to heal the new opening, as if it was an injury. Many surgeons perform trabeculectomy with an anti-fibrotic agent that is placed on the eye during surgery and reduces such scarring during the healing period. The most common anti-fibrotic agent is Mitomycin-C. Another is 5-Fluorouracil, or 5-FU.
About 50 percent of patients no longer require glaucoma medications after surgery for a significant length of time. Thirty-five to 40 percent of those who still need medication have better control of their IOP. A trabeculectomy is usually an outpatient procedure. The number of post-operative visits to the doctor varies, and some activities, such as driving, reading, bending and heavy lifting must be limited for two to four weeks after surgery.
Drainage Implant SurgerySeveral different devices have been developed to aid the drainage of aqueous humor out of the anterior chamber and lower IOP. All of these drainage devices share a similar design which consists of a small silicone tube that extends into the anterior chamber of the eye. The tube is connected to one or more plates, which are sutured to the surface of the eye, usually not visible. Fluid is collected on the plate and then absorbed by the tissues in the eye. This type of surgery is thought to lower IOP less than trabeculectomy but is preferred in patients whose IOP cannot be controlled with traditional surgery or who have previous scarring.
Nonpenetrating SurgeryNewer nonpenetrating glaucoma surgery, which does not enter the anterior chamber of the eye, shows great promise in minimizing postoperative complications and lowering the risk for infection. However, such surgery often requires a greater surgical acument and generally does not lower IOP as much as trabeculectomy. Furthermore, long term studies are needed to assess these procedures and to determine their role in the clinical management of glaucoma patients.
Some Promising Surgical Alternatives The ExPress mini glaucoma shunt is a stainless steel device that is inserted into the anterior chamber of the eye and placed under a scleral flap. It lowers IOP by diverting aqueous humor from the anterior chamber. The ExPress offers the glaucoma surgeon an alternative to either repeating a trabeculectomy or placing a more extensive silicone tube shunt in those patients whose IOP is higher than the optic nerve can tolerate.
The Trabectome is a new probe-like device that is inserted into the anterior chamber through the cornea. The procedure uses a small probe that opens the eye's drainage system through a tiny incision and delivers thermal energy to the trabecular meshwork, reducing resistance to outflow of aqueous humor and, as a result, lowering IOP.
Canaloplasty, a recent advancement in non-penetrating surgery, is designed to improve the aqueous circulation through the trabecular outflow process, thereby reducing IOP. Unlike traditional trabeculectomy, which creates a small hole in the eye to allow fluid to drain out, canaloplasty has been compared to an ocular version of angioplasty, in which the physician uses an extremely fine catheter to clear the drainage canal.
Glaucoma eye drops do have significant side effects and it’s best if you can stop taking them provided you have an alternative and that alternative may be laser surgery. Sometimes glaucoma medications don’t work.
Simply- glaucoma is an eye disease of which there are two basic kinds – primary open angle and acute angle-closure.
There is a clear fluid that flows though the passages of your eye. Sometimes these passages get blocked and the fluid will build up in the eye and cause too much pressure. This pressure can cause damage to the optic nerve and a loss of vision. The result is glaucoma.
Laser surgery uses a tiny but powerful light beam to help drain the fluid from your eye easier. The eye surgeon will make holes or use it to shrink the clogged areas in your eye. This surgery can help you decrease your eye pressure. The surgery may be done on one or both eye. It can affect one eye only.
The surgery is done in your doctors’ office or in a clinic. You should be able to see just fine after surgery except you may feel some grittiness in your eye or eyes. Your eye or eyes may be swollen too. But these symptoms will go away in a day or two. You may have some sensitivity to light and some blurred vision for three weeks or so while your eyes heal. You would still take your eye drops or oral medications during this time period.
Now this is the basic procedure is for glaucoma laser surgery. Your ophthalmologist can fill you in more fully as it applies to your individual eye problem.
It’s important to note that any lost vision won’t return. This surgery is meant to prevent future loss of vision and help you avoid taking lifetime medications that may be harmful to your body. Laser surgery may not be appropriate for all types of glaucoma but your eye surgeon or ophthalmologist will help determine that. In any case glaucoma laser surgery is a consideration and want to avoid eye drops and seek a better solution.
Lasik Eye Surgery.
Lasik eye-surgery is the gift of science to mankind, as it is efficient in rectifying vision. People with conditions of astigmatism and myopia are largely opting for laser eye – surgery, which has high percentage of positive results and the nature of the surgery itself is simple and painless that draws so much popularity. Lasik is the laser eye_surgery that involves least complicated procedure, which removes the corneal tissue accurately and reshapes the cornea to gain more power while focusing. The Laser eye surgery has broken the conventional barriers of using glasses or lenses as vision corrective measures.
Precautions before eye Surgery
Before going for eye-surgery it is necessary for individuals to disclose to the doctor if they have any infections or allergies so that the existing conditions can be treated first to avoid further complications. Even your physical conditions also play a major role so it is safe to bring to the notice of your ophthalmologist before the eye_surgery so that he can take a suitable decision
Precautions before eye Surgery
Before going for eye-surgery it is necessary for individuals to disclose to the doctor if they have any infections or allergies so that the existing conditions can be treated first to avoid further complications. Even your physical conditions also play a major role so it is safe to bring to the notice of your ophthalmologist before the eye_surgery so that he can take a suitable decision
When do you need eye surgery?
Beauty lies in the eyes of the beholder- yes; your eyes are a vital pair of sensory organs that the above statement partially describes their purpose.
Eyes are highly sensitive organs that demand a lot of care and attention and it does not require to be told the importance of this visual asset. Of course, individuals cannot determine the requirement of eye surgery, it is the job of an ophthalmologist who are skilled professionals having the license to carry out a surgical procedure on your eyes based on the diagnosis.
Eye-surgery has different terminologies such as orogolomistician aka ocular surgery is rather a very complex procedure that requires professional acumen. The most common eye_surgery is the cataract, which is carried out normally on aging people due to the crystalline lens getting cloudy and barring the light to create a clear picture on the retina. Based on the severity of the situation the ophthalmologist will be able to guide you with the suitable surgical procedure. Glaucoma is another medical condition that damages the optic nerve and might result in visual loss but the different glaucoma eye-surgeries can certainly help you to combat the disease.
Then you also have the refractive surgery that will correct the refractory errors in the eye to avoid the use of lenses. The other common kind of eye surgery is Eye muscle surgery that basically alters the strabismus and involves many more corrective measures. Eye-surgery is also performed on repair fractures due to injury, to remove tumours and even as a facelift measure that solely depends on the ophthalmologist to decide the kind of surgery you need based on the problem.
Eyes are highly sensitive organs that demand a lot of care and attention and it does not require to be told the importance of this visual asset. Of course, individuals cannot determine the requirement of eye surgery, it is the job of an ophthalmologist who are skilled professionals having the license to carry out a surgical procedure on your eyes based on the diagnosis.
Eye-surgery has different terminologies such as orogolomistician aka ocular surgery is rather a very complex procedure that requires professional acumen. The most common eye_surgery is the cataract, which is carried out normally on aging people due to the crystalline lens getting cloudy and barring the light to create a clear picture on the retina. Based on the severity of the situation the ophthalmologist will be able to guide you with the suitable surgical procedure. Glaucoma is another medical condition that damages the optic nerve and might result in visual loss but the different glaucoma eye-surgeries can certainly help you to combat the disease.
Then you also have the refractive surgery that will correct the refractory errors in the eye to avoid the use of lenses. The other common kind of eye surgery is Eye muscle surgery that basically alters the strabismus and involves many more corrective measures. Eye-surgery is also performed on repair fractures due to injury, to remove tumours and even as a facelift measure that solely depends on the ophthalmologist to decide the kind of surgery you need based on the problem.
Friday, February 19, 2010
Who is at risk of developing glaucoma? How is it detected, and how is it treated?
FOR a moment, keep your eyes focused on the last word in this sentence. Without moving your eyes, could you see some of the area above, below, and on either side of this magazine? Most likely you could, thanks to what is known as peripheral vision. This ability makes you aware of that suspicious-looking person who is approaching you from the side. It helps you to sidestep objects on the ground and avoid bumping into walls as you walk. And if you drive a car, peripheral vision can alert you that a pedestrian has stepped off the curb.
But even as you read this page, your peripheral vision could slowly be disappearing—without your even realizing it. Worldwide, an estimated 66 million people are affected by a group of eye diseases collectively known as glaucoma. Of that number, over five million have become totally blind, making glaucoma the third-largest cause of permanent blindness. “Yet even in developed countries with public educational programmes that target glaucoma, half of the individuals with glaucoma remain undiagnosed,” states the medical journal The Lancet.
Glaucoma could steal up to 90 percent of your vision in one eye without your being aware of it. How is that possible? All of us have a naturally occurring blind spot at the back of each eye. This spot on the retina, where your nerve fibers join together to form the optic nerve, is devoid of light-sensing cells. You are unaware of this blind spot, however, because your brain has the ability to “paint in” the missing bits of the picture. Ironically, it is the brain’s ability to do this that makes glaucoma so insidious.
Dr. Ivan Goldberg, a leading Australian ophthalmologist, told Awake!: “Glaucoma is called the sneak thief of sight because it doesn’t give you any symptoms. The most common kind of glaucoma is slow and steady and, without any warning, causes damage to the nerve structure that connects the eye to the brain. Whether your eyes water or they don’t, whether they are dry or not, whether they see clearly to read and write or they don’t has nothing to do with glaucoma. You can have perfectly comfortable eyes and have very bad glaucoma.”
Detecting the Thief
Unfortunately, there is no single comprehensive test for glaucoma. Using a device known as a tonometer, an eye specialist may start by checking the fluid pressure in your eyes. The instrument is used gently to flatten the cornea, or front part of your eye. The amount of force required to perform this task is measured, and in this way the pressure inside your eye can be gauged. The eye specialist may also look for signs of glaucoma by using instruments that identify damaged tissue in the nerve structure that connects the eye to the brain. Dr. Goldberg says: “We see if the nerve fibers or blood vessels at the back of the eye are unusual in shape, because that can be an indication that nerves are being damaged.”
Glaucoma is also detected by visual-field testing. Dr. Goldberg explains: “A person looks into a bowl of white light, and there is a brighter white light that is shone at a little spot inside that bowl. The person responds by pressing a button when he or she can see the little white light.” Failure to recognize the white light when it is at the outer edge of your visual field could indicate glaucoma. New instruments are being developed that might simplify this rather tedious procedure.
Dr. Kevin Greenidge of the Glaucoma Foundation in the United States highlights other risk factors, saying: “If you are over 45 and of African descent, or if you have any of these risk factors—family history of glaucoma, nearsightedness, diabetes, a previous eye injury or regular use of cortisone/steroid products—get your eyes tested every year.” Even if you have no risk factors and are under 45, the foundation recommends that you still have your eyes checked for glaucoma every four years. If you are over 45, you should have this checkup every two years.
But even as you read this page, your peripheral vision could slowly be disappearing—without your even realizing it. Worldwide, an estimated 66 million people are affected by a group of eye diseases collectively known as glaucoma. Of that number, over five million have become totally blind, making glaucoma the third-largest cause of permanent blindness. “Yet even in developed countries with public educational programmes that target glaucoma, half of the individuals with glaucoma remain undiagnosed,” states the medical journal The Lancet.
Glaucoma could steal up to 90 percent of your vision in one eye without your being aware of it. How is that possible? All of us have a naturally occurring blind spot at the back of each eye. This spot on the retina, where your nerve fibers join together to form the optic nerve, is devoid of light-sensing cells. You are unaware of this blind spot, however, because your brain has the ability to “paint in” the missing bits of the picture. Ironically, it is the brain’s ability to do this that makes glaucoma so insidious.
Dr. Ivan Goldberg, a leading Australian ophthalmologist, told Awake!: “Glaucoma is called the sneak thief of sight because it doesn’t give you any symptoms. The most common kind of glaucoma is slow and steady and, without any warning, causes damage to the nerve structure that connects the eye to the brain. Whether your eyes water or they don’t, whether they are dry or not, whether they see clearly to read and write or they don’t has nothing to do with glaucoma. You can have perfectly comfortable eyes and have very bad glaucoma.”
Detecting the Thief
Unfortunately, there is no single comprehensive test for glaucoma. Using a device known as a tonometer, an eye specialist may start by checking the fluid pressure in your eyes. The instrument is used gently to flatten the cornea, or front part of your eye. The amount of force required to perform this task is measured, and in this way the pressure inside your eye can be gauged. The eye specialist may also look for signs of glaucoma by using instruments that identify damaged tissue in the nerve structure that connects the eye to the brain. Dr. Goldberg says: “We see if the nerve fibers or blood vessels at the back of the eye are unusual in shape, because that can be an indication that nerves are being damaged.”
Glaucoma is also detected by visual-field testing. Dr. Goldberg explains: “A person looks into a bowl of white light, and there is a brighter white light that is shone at a little spot inside that bowl. The person responds by pressing a button when he or she can see the little white light.” Failure to recognize the white light when it is at the outer edge of your visual field could indicate glaucoma. New instruments are being developed that might simplify this rather tedious procedure.
Who Is at Risk?Paul is a healthy man in his early 40’s. He says: “I went to the optometrist to be tested for a new pair of glasses, and during the visit he asked me if I had a family history of glaucoma. I did some investigating and discovered that both an aunt and an uncle had this condition. I was referred to an eye specialist, who confirmed that I had glaucoma.” Dr. Goldberg explains: “If your mother or father has it, your risk of getting glaucoma goes up three to five times. And if you have a brother or a sister with glaucoma, then your risk of getting it goes up between five and seven times.”
Dr. Kevin Greenidge of the Glaucoma Foundation in the United States highlights other risk factors, saying: “If you are over 45 and of African descent, or if you have any of these risk factors—family history of glaucoma, nearsightedness, diabetes, a previous eye injury or regular use of cortisone/steroid products—get your eyes tested every year.” Even if you have no risk factors and are under 45, the foundation recommends that you still have your eyes checked for glaucoma every four years. If you are over 45, you should have this checkup every two years.
The pressure inside your eye.....
First we need to understand a little about our eyes. A brochure produced by the Glaucoma Foundation of Australia explains: “The eye’s rigidity is obtained through pressure—the soft tissues of the eye are ‘pumped up,’ just like a car tyre or a balloon.” Inside the eye, a pump called the ciliary body moves a fluid known as aqueous humor from the blood vessels into the eye. “The aqueous circulates deep inside the eye, nourishing the living structures of the eye and returns to the blood stream through a strainerlike structure called the trabecular meshwork.”
If this meshwork becomes blocked or constricted for any reason, the pressure inside the eye will increase and eventually begin to damage the delicate nerve fibers at the back of the eye. This condition is called open-angle glaucoma and accounts for about 90 percent of all cases.
The pressure inside your eye, known as intraocular pressure (IOP), can vary from hour to hour and is affected by a variety of factors including your heartbeat, the amount of fluids you drink, and your body position. These natural variations cause no damage to your eye. High pressure in the eye is not by itself proof of glaucoma, since “normal” eye pressure varies from person to person. Still, high IOP is one of the indicators of glaucoma.
A rare form of this disease is called acute, or angle-closure, glaucoma. Unlike open-angle glaucoma, this type involves a sudden increase of pressure in the eye. It causes severe pain in the eye, along with blurred vision and vomiting. If not treated within hours of the onset of symptoms, it will often cause blindness. Another category is called secondary glaucoma. As the name implies, this type is triggered by such other conditions in the eye as tumors, cataracts, or eye injuries. A small group of people are afflicted by the fourth type, known as congenital glaucoma. This type is present at birth or shortly thereafter and is indicated if the infant has enlarged eyeballs and an increased sensitivity to light.
If this meshwork becomes blocked or constricted for any reason, the pressure inside the eye will increase and eventually begin to damage the delicate nerve fibers at the back of the eye. This condition is called open-angle glaucoma and accounts for about 90 percent of all cases.
The pressure inside your eye, known as intraocular pressure (IOP), can vary from hour to hour and is affected by a variety of factors including your heartbeat, the amount of fluids you drink, and your body position. These natural variations cause no damage to your eye. High pressure in the eye is not by itself proof of glaucoma, since “normal” eye pressure varies from person to person. Still, high IOP is one of the indicators of glaucoma.
A rare form of this disease is called acute, or angle-closure, glaucoma. Unlike open-angle glaucoma, this type involves a sudden increase of pressure in the eye. It causes severe pain in the eye, along with blurred vision and vomiting. If not treated within hours of the onset of symptoms, it will often cause blindness. Another category is called secondary glaucoma. As the name implies, this type is triggered by such other conditions in the eye as tumors, cataracts, or eye injuries. A small group of people are afflicted by the fourth type, known as congenital glaucoma. This type is present at birth or shortly thereafter and is indicated if the infant has enlarged eyeballs and an increased sensitivity to light.
Types of Glaucoma.
Open Angle GlaucomaNinety percent of glaucoma cases are open angle glaucoma. It is also known as primary open angle glaucoma or chronic glaucoma. This occurs due to the blockage of the trabecular meshwork. In this type of glaucoma, the fluid build up occurs slowly. As a result, it takes considerable time for the sufferer to recognize the symptoms of the disease.
Closed angle glaucomaAlso known as angle closure glaucoma or acute glaucoma, it occurs in nearly 9 percent of glaucoma patients. This occurs when the drainage of the aqueous humor is blocked by the narrowing of the opening between the cornea and iris. The type of glaucoma develops rapidly.
Secondary glaucomaThis form of glaucoma occurs because of eye injury, advanced stage of cataract, inflammation or eye tumor or diabetes.
Normal tension glaucomaIn this form of glaucoma, the optic nerve is damaged even when the intraocular pressure remains in the normal range.
Congenital glaucoma
This occurs due to incorrect development of the drainage systems of the eye in the prenatal period.
Glaucoma.
Glaucoma is one of the major causes of blindness throughout the world. Rise in the intraocular pressure due to build up of the aqueous humor in the eye, causes Glaucoma. If left untreated, the rising fluid pressure damages the optic nerve, which is the main nerve of the eye linked to the brain, and results in loss of vision.
Aqueous humor is secreted constantly by the ciliary tissues. This fluid is responsible for the nourishment of your cornea, lens and the iris and for maintaining the shape of your eyes. It circulates in the space between the iris and the cornea. Since it is produced every hour, it also needs to be drained every hour. The ‘drainage angle’ is located at the point where the iris and the cornea meet. From here the fluid passes through the valve, dubbed the trabecular meshwork, which regulates the eye pressure, to the canal of Schlemm. From here, the fluid flows out of the eyes through a network of small veins, known as the drainage canals. If for some reason, there is some blockage in the normal drainage process the increased fluid build up in the eye increases the pressure on the optic nerve and if the condition remains for a long time, the optic nerve will suffer permanent damage.
Open Angle Glaucoma
Ninety percent of glaucoma cases are open angle glaucoma. It is also known as primary open angle glaucoma or chronic glaucoma. This occurs due to the blockage of the trabecular meshwork. In this type of glaucoma, the fluid build up occurs slowly. As a result, it takes considerable time for the sufferer to recognize the symptoms of the disease.
Aqueous humor is secreted constantly by the ciliary tissues. This fluid is responsible for the nourishment of your cornea, lens and the iris and for maintaining the shape of your eyes. It circulates in the space between the iris and the cornea. Since it is produced every hour, it also needs to be drained every hour. The ‘drainage angle’ is located at the point where the iris and the cornea meet. From here the fluid passes through the valve, dubbed the trabecular meshwork, which regulates the eye pressure, to the canal of Schlemm. From here, the fluid flows out of the eyes through a network of small veins, known as the drainage canals. If for some reason, there is some blockage in the normal drainage process the increased fluid build up in the eye increases the pressure on the optic nerve and if the condition remains for a long time, the optic nerve will suffer permanent damage.
Open Angle Glaucoma
Ninety percent of glaucoma cases are open angle glaucoma. It is also known as primary open angle glaucoma or chronic glaucoma. This occurs due to the blockage of the trabecular meshwork. In this type of glaucoma, the fluid build up occurs slowly. As a result, it takes considerable time for the sufferer to recognize the symptoms of the disease.
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