Transcript Document
Glaucoma
Information and Detection January 2009
The healthy eye
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Light rays enter the eye through the cornea, pupil and lens.
• These light rays are focused directly onto the retina, the light-sensitive tissue lining the back of the eye.
• The retina converts light rays into impulses; sent through the optic nerve to your brain, where they are recognized as images.
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What is glaucoma?
• Disease of the optic nerve.
• When damage to the optic nerve fibers occurs, blind spots develop; blind spots usually go undetected until optic nerve is significantly damaged.
• Leading cause of blindness in the United States, especially for older people.
• Early detection and treatment are keys to preventing vision loss from glaucoma.
2 Normal vision Vision as it might be affected by glaucoma
Anatomy of glaucoma
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Clear liquid called aqueous humor circulates inside the front portion of the eye.
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To maintain a healthy level of pressure within the eye, a small amount of aqueous humor is produced constantly, while an equal amount flows out of the eye through a microscopic drainage system —the trabecular meshwork.
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Anatomy of glaucoma
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With glaucoma, aqueous humor does not flow through the trabecular meshwork properly.
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Over time, eye pressure IOP increases, damaging the optic nerve fibers.
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Types of glaucoma
Two main categories of glaucoma:
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Open-angle glaucoma: the most common form of glaucoma (the most common form that affects approximately 95% of individuals)
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Closed-angle glaucoma: a less common and more urgent form of glaucoma.
Other Types of glaucoma:
Normal-Tension Glaucoma
Congenital glaucoma
Juvenile glaucoma
Secondary glaucoma 5
Types of glaucoma – Open-angle
Open-angle glaucoma
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Trabecular meshwork becomes less efficient at draining aqueous humor.
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Intraocular pressure (IOP) builds up, which leads to damage of the optic nerve.
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Damage to the optic nerve occurs at different eye pressures among different patients.
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Typically, glaucoma has no symptoms in its early stages.
6 Open-angle glaucoma
Types of glaucoma – Open-angle
Open-angle glaucoma is the most common form of the disease, is progressive and characterized by optic nerve damage. The most significant risk factor for the development and advancement of this form is high eye pressure. Initially, there are usually no symptoms, but as eye pressure gradually builds, at some point the optic nerve is impaired, and peripheral vision is lost. Without treatment, an individual can become totally blind.
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Glaucoma risk factors – Open-angle
Strong risk factors for open-angle glaucoma include:
High eye pressure (IOP)
Family history of glaucoma
Age 40 and older for African Americans
Age 60 and older for the general population, especially Mexican Americans
Thin cornea
Suspicious optic nerve appearance with increased cupping (size of cup, the space at the center of optic nerve, is larger than normal)
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Glaucoma risk factors – Open-angle (cont)
Additional risk factors for open-angle glaucoma include:
High myopia (severe nearsightedness)
Diabetes
Eye surgery or injury
High blood pressure
Use of corticosteroids (for example, eye drops, pills*, inhalers and creams) 9
Types of glaucoma – Closed-angle
Closed-angle (or narrow-angle) glaucoma: • The drainage angle of trabecular meshwork becomes blocked by the iris.
• IOP builds up very fast.
• Symptoms include severe eye or brow pain, redness of the eye, decreased or blurred vision.
• Must be treated as a medical emergency —must visit ophthalmologist immediately.
Closed-angle glaucoma 10
Types of glaucoma – Closed-angle
Closed-angle glaucoma may be acute or chronic. In acute closed-angle glaucoma the normal flow of eye fluid (aqueous humor) between the iris and the lens is suddenly blocked. Symptoms may include severe pain, nausea, vomiting, blurred vision and seeing a rainbow halo around lights. Acute closed-angle glaucoma is a medical emergency and must be treated immediately or blindness could result in one or two days. Chronic closed-angle glaucoma progresses more slowly and can damage the eye without symptoms, similar to open-angle glaucoma.
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Glaucoma risk factors – Closed-angle
Closed-Angle Glaucoma
Age
Family history
Poor short-distance vision (farsightedness)
Eye injury or eye surgery
East Asian and Inuit ethnicity 12
Types of glaucoma
Normal-Tension Glaucoma
Cardiovascular disease
Family history of glaucoma
Japanese ethnicity
Low eye pressure IOP Normal-tension glaucoma occurs when eye pressure is normal, yet the optic nerve is damaged and peripheral vision is lost. Lowering eye pressure through medication sometimes slows the progress of the disease, but this type of glaucoma may worsen despite low pressure. Treatment is generally the same as for open-angle glaucoma with high eye pressure.
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Types of Glaucoma
Congenital glaucoma affects infants born with defects that prevent the normal drainage of fluid from the eye.
Juvenile glaucoma is open-angle glaucoma that affects children, adolescents and young adults.
Secondary glaucoma can be open-angle or closed-angle, and is the result of some other medical condition in the eye or the body.
Examples of secondary glaucoma include: Pigmentary glaucoma, a rare form, in which pigment granules from the iris flake off into the eye fluid (aqueous humor) and clog the eye’s drainage system (trabecular meshwork). Pseudoexfoliation Syndrome occurs when white material appears to flake off the lens of the eye and block normal flow of the aqueous humor.
Neovascular glaucoma occurs when abnormal blood vessel growth blocks the eye’s fluid drainage channels and leads to increased eye pressure. This abnormal growth can be caused by low blood supply to the eye due to diabetes, insufficient blood flow to the head because of blocked neck arteries, or blood vessel blockage in the back of the eye.
Iridocorneal Endothelial Syndrome (ICE) has a number of features, including the breaking off of cells from the cornea, which blocks the drainage channels in the eye and leads to increased eye pressure. Scars may also connect the iris to the cornea.
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Detecting Glaucoma
Regular glaucoma check-ups include two routine eye tests: 1.
Tonometry – eye pressure test IOP 2.
Ophthalmoscopy is a test that allows a health professional to see inside the back of the eye (called the fundus) and other structures using a magnifying instrument (ophthalmoscope) and a light source. Additional tests: Perimetry (the perimetry test is also called a visual field test) Gonioscopy is a painless eye test that checks if the angle where the iris meets the cornea is open or closed, showing if either open angle or closed angle glaucoma is present.
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Detecting Glaucoma Tonometry:
The tonometry eye test measures the inner pressure of the eye also known as Intraocular Pressure or IOP.
Tonometry is carried out by an instrument called a TONOMETER.
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Types of Tonometry:
Applanation tonometry measures intraocular pressure either by the force required to flatten a constant area of the cornea (e.g. Goldmann tonometry) or by the area flattened by a constant force.
Goldmann tonometer: Stationary device requires anesthesia drops, requires contact with cornea and is attached to a slit lamp – usually is used by an Ophthalmologist.
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Types of tonometry
non-contact tonometry or air-puff tonometry: This type of tonometer uses a rapid air pulse to applanate the cornea. Intraocular pressure is estimated by detecting the force of the air jet at the instance of applanation. In most cases a stationary unit, Does not require anesthetic drops 18
Types of tonometry
Tono-pen - is a portable electronic, digital pen-like instrument that determines IOP by making contact with the cornea, after use of topical anesthetic eye drops – tip covers are used between the patients.
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Types of tonometry
The newest Advancement in tonometry is DIATON TONOMETER – It measures intraocular pressure (IOP) through the Eyelid.
DIATON Requires No Contact with Cornea No Anesthetic Drops, No Risk of Infecting Diaton Tonometer is intended for use by Inpatient & Outpatient Clinics such as Hospitals, Emergency Rooms, Nursing & Elderly Homes, General & Specialty Practitioners as well as Ophthalmologists and Optometrists.
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Diaton Tonometry
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Safe
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Quick
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Efficient
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Painless
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Noninvasive 21 Can be used on Children and Adults
Four Key Facts About Glaucoma
Glaucoma is a leading cause of blindness Glaucoma can cause blindness if it is left untreated. And unfortunately approximately 10% of people with glaucoma who receive proper treatment still experience loss of vision.
There is no cure (yet) for glaucoma Glaucoma is not curable, and vision lost cannot be regained. With medication and/or surgery, it is possible to halt further loss of vision. Since glaucoma is a chronic condition, it must be monitored for life.
Screening, detection and prevention is the first step to preserving your vision.
Everyone is at risk for glaucoma Everyone is at risk for glaucoma from babies to senior citizens. Yes, older people are at a higher risk for glaucoma but babies can be born with glaucoma (approximately 1 out of every 10,000 babies born in the United States).
Young adults can get glaucoma, too. African-Americans in particular are susceptible at a younger age.
There may be no symptoms to warn you With open angle glaucoma, the most common form, there are virtually no symptoms. Usually, no pain is associated with increased eye pressure.
Vision loss begins with peripheral or side vision. You may compensate for this unconsciously by turning your head to the side, and may not notice anything until significant vision is lost. The best way to protect your sight from glaucoma is to get tested. If you have glaucoma, treatment can begin immediately.
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Statistics About Glaucoma
It is estimated that over 4 million Americans have glaucoma but only half of those know they have it. (1)
Approximately 120,000 are blind from glaucoma, accounting for 9% to 12% of all cases of blindness in the U.S. (2)
About 2% of the population ages 40-50 and 8% over 70 have elevated IOP.
Glaucoma is the second leading cause of blindness in the world, according to the World Health Organization.
Glaucoma is the leading cause of blindness among African-Americans. (2)
Glaucoma is 6 to 8 times more common in African-Americans than Caucasians. (3)
African-Americans ages 45-65 are 14 to 17 times more likely to go blind from glaucoma than Caucasians with glaucoma in the same age group.
The most common form, Open Angle Glaucoma, accounts for 19% of all blindness among African Americans compared to 6% in Caucasians. (4)
Other high-risk groups include: people over 60, family members of those already diagnosed, diabetics, and people who are severely nearsighted.
Estimates put the total number of suspected cases of glaucoma at around 65 million worldwide. (5) 23
Statistics About Glaucoma cont Prevent Blindness America Survey found that:
Blindness ranked third (after cancer and heart disease) as people’s major fear.
20% of people knew that glaucoma was related to elevated pressure within the eye. Most of them mistakenly thought people could tell if they had glaucoma due to symptoms, or that it was easily cured, or that it did not lead to blindness.
50% had heard of glaucoma, but weren’t sure what it was.
30% had never heard of glaucoma. 24
Statistics About Glaucoma
Economic Impact:
Glaucoma accounts for over 7 million visits to physicians each year. (1)
In terms of Social Security benefits, lost income tax revenues, and health care expenditures, the cost to the U.S. government is estimated to be over $2.5 billion annually. (6)
Sources: (1) Prevent Blindness America; (2) National Eye Health Program/National Institutes of Health; (3) American Academy of Ophthalmology; (4) Racial differences in the cause-specific prevalence of blindness in east Baltimore. N Engl J Med. 1991 Nov 14;325(20):1412 7; (5) Quigley, “Number of people with glaucoma worldwide,” 1996; (6) NEI, Report of the Glaucoma Panel, Fall 1998
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Statistics About Glaucoma
60 million Americans are at RISK for developing Glaucoma, as per University of Washington Department of Ophthalmology.
In U.S. - there are ONLY: 17,000 Ophthalmologists & 30,000 Optometrists There is a great NEED for ADDITIONAL screening locations… 26
FLORIDA AGE DEMOGRAPHICS:
Florida Households All Age 65+ Alone 6337929 1943478 710025 National % National 105480101 6% 24672708 7.9% 9722857 7.3% Not Alone 1233453 45 to 54 years 2069479 55 to 59 years 60 to 64 years 821517 737496 14949851 8.3% 37677952 5.5% 13469237 6.1% 10805447 6.8% 65 to 74 years 75 to 84 years 85 years and over 1452176 1024134 331287 18390986 7.9% 12361180 8.3% 4239587 7.8% TOTAL AT RISK (45 years and older) 6,436,089 As population ages the impact of the disease will increase… 27
Glaucoma Prevention Initiative Thank you for your attention and your openness to challenge the “silent thief of sight”!
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